1. A lnobile con~municationn etwork system comprising a core network accessed from a mobile terminal through a radio line, wherein 5 in a detach request signal that requests detach being received from the mobile terminal, the radio line is released in a state of holding a communication session of the core network side set in the mobile terminal having attached, and in an attach request signal that requests attach being received from the mobile terminal, the held communication session of the core network side is used, 10 and setting of the radio line is performed.

2. The mobile communication network system according to Claim 1, wherein a mobile management node arranged on the core network side in order to perform management control of mobile communication determines whether or not detach 15 processing and attach processing of the core network side are omitted depending on terminal information and subscriber information that indicate attributes of the mobile terminal, or depending on a parameter addcd to the attach request signal and the detach request signal. 20 3. The mobile communication network system according to Claim 1 or 2, wherein when receiving the detach request signal from the mobile terminal, and omitting the detach processing of the core network side, a mobile management node arranged on the core network side in order to perform management control of mobile communication sets to a session holding timer a time a little longer by a 2 5 predetermined time than a generation interval of a reattachlredetach requcst from the mobile terminal as a time to wait for forced release of the held communication session, and when the session holding timer expires without receiving the attach request signal from the mobile terminal, the mobile management node deletes infornlation on the held communication session by making usual detach processing 30 of the core network side carried out, and forcibly releases the commuilication session.

4. The mobile comlnunication network system according to Claim 3, wherein when omitting the detach processing of the core network side in receiving the 39 detach request signal from the mobile ternlinal, and setting to the session holding timer the time to wait for forced release of the held corn~nunications ession, the mobile managetnent node stops a tinler for periodically updating a routing area, and cancels a subsequent paging request until a reattach request from the mobile 5 terminal is generated, or the session holding timer expires.

5. The mobile co~nmunicationn etwork system according to any of Claims 1 to 4, wherein a mobile management node arranged on the core network side in order to perform management control of mobile communication is a packet switch SGSN 10 (Serving GPRS (General Packet Radio Service) Support Node) established in a 3GPP standard, or a mobile management node MME (Mobility Management Entity).

6. A communication control method used in a mobile communication network 15 system comprising a core network accessed from a mobile terminal through a radio line, wherein in a detach request signal that requests detach being received from the mobile terminal, the radio line is released in a state of holding a communication session of the core network side set in the mobile terminal having attached, and 2 0 in an attach request signal that requests attach being received from the mobile terminal, the held communication session of the core network side is used, and setting of the radio line is performed.

7. The communication control method according to Claim 6, wherein a nlobile 2 5 nlanagelnent node arranged on the core network side in order to perform management control of mobile communication determines whether or not detach processing and attach processing of the core network side are omitted depending on terminal information and subscriber information that indicate attributes of the mobile terminal, or depending on a parameter added to the attach request signal 3 0 and the detach request signal.

8. The communication control method according to Claim 6 or 7, wherein when receiving the detach request signal from the mobile terminal, and omitting the detach processing of the core network side, a mobile management node 40 arranged on the core nctwork side in order to perform managcrncnt control of mobile communication sets to a session holding timer a time a little longer by a predeternlincd time than a generation interval of a reatiachlredeiach request from the mobile terminal as a time to wait for forced release of the held communication 5 session, and after that, when the session holding timer expires without receiving the attach request signal from the mobile terminal, the mobile management node deletes information on the held communication session by making usual detach processing of the core network side carried out, and forcibly releases the communication session. 10

9. The communication control method according to Claim 8, wherein when omitting the detach processing of the core network side in receiving the detach request signal from the mobile terminal, and setting to the session holding timer the time to wait for forced release of the held comn~unications ession, the mobile 15 management node stops a timer for periodically updating a routing area, and cancels a subsequent paging request until a reattach request from the mobile terminal is generated, or the session holding timer expires.

10. A non-transitory computer readable medium storing a mobile terminal 2 0 attachldetach processing program for making a computer provided at a mobile management node arranged on the core network side in order to perform management control of mobile communication execute the communication control method according to any of Claims 6 to 9.

DESCRIPTION
MOBILE COMMIJNICATION NETWORK SYSTEM, COMMUNICATION
CONTROL METHOD, NON-TRANSITORY COMPUTER READABLE MEDIUM
5 STORING PROGRAM THEREFOR
Technical Field
[OOO 11
The present invention relates to a mobile communication network system, a
10 comtnunication control method, and a mobile terminal attachldetach processing
program and, in particular, to a mobile communication network systcnl, a
communication control method, and a mobile terminal attachldetach processing
program that make it possible to decrease a load of a core network (core node) side
at the time of attachldetach to the core network of a mobile terminal (radio
15 con~municationte rminal).
Background Art
100021
Progress of a radio conlmunication technology in recent years is
2 0 remarkable, and various standards have been energetically established in the 3GPP
(Third Generation Partnership Project) also regarding a 3G (Third Generation)
system and a more advanced mobile communication network system.
Furthermore, as described in Japanese Unexamined Patent Application Publication
No. 2009-246772 of Patent Literature 1 "MOBILE MANAGEMENT DEVICE AND
25 RADIO COMMUNICATION BASE STATION DEVICE", and Published Japanese
Translation of PCT Inter~lationalP ublication for Patent Application, No.
2009-516399 of Patent Literature 2 "RADIO COMMUNICATION SYSTEM AND
METHOD FOR IMPLEMENTING ADVANCED SYSTEM, ATTACH PROCESSING
PROCEDURE", etc., trials to achieve high-speed and large-volume packet
30 communication as a nlobile communication network system based on a 3GPP
standard have been actively performed.
[0003]
In such circunlstances, when a large amount of mobile terminals (radio
con~municationt crminals), such as mobile phones and M2Ms (Machine-to-Machine
or Machine-to-Management), exist on a network, an attachldetach request that
requests co~~nection/openinwgi th the network is performed to a core network side
from the large amount of mobile terminals (radio communication terminals) on the
network. When such request is frequently generated, significant loads are applied
5 to the core network and a core node, and congestion and a device failure may be
caused.
[0004]
Meanwhile, a case also exists where depending on applications of terminals
such as the M2M, positional movement is not performed and update of session
10 information is not needed each time. Accordingly, in such case, it is necessary to
take measures so that the loads of the core network and the core node are decreased
by reducing attachldetach processing to thereby decrease generation factors of the
congestion and the device failure of the core network and the core node.
15 Citation List
Patent Literature
[0005]
Patent Literature 1 : Japanese Unexamined Patent Application Publication
No. 2009-246772 (Pages 4 to 9)
2 0 Patent Literature 2: Published Japanese Translation of PCT International
Publication for Patent Application, No. 2009-516399 (Pages 9 to 12)
Summary of Invention
Technical Problem
25 [0006]
IHowever, in a related art, there has not existed a processing reduction
technique in co~lsciousness of a load of attachldetach processing. That is, in
conventional processing of a core network side, processing was uniformly
performed to mobile terminals (radio communication terminals) that were
30 performing attach and detach as positional movement being performed regarding
all the mobile terminals (radio conlmunication terminals) without being conscious
of features of the mobile terminals (radio conlmunication terminals).
[0007]
IHowever, as mentioned above, there also exists a mobile terminal (radio
colnmunication terminal) that is not moved, and perfor~nsth e attachldetach request
only approximately oncc a day. Conventionally, as for the processing of the core
network side, the same processing has been repeated also to such mobile terminal
(radio communication terminal) each time in each case, and loads have been
5 uselessly applied to the core network and the core node.
[0008]
(Object of Invention)
The present invention has been made in view of such circumstances, and an
object thereof is to provide a mobile con~municationn etwork system, a
10 commnnication control method, and a mobile terminal attachldetach processing
program that makc it possible to decrease a load of a core network side at the time
of attachldetach of a mobile terminal.
Solution to Problem
15 [0009]
In order to solve the above-mentioned problem, the following characteristic
configurations are mainly employed in a mobile communication network system, a
communication control method, and a mobile terminal attachldetach processing
program according to the present invention.
20 [OOlO]
(1) A mobile communication network system according to the present
invention that is provided with a core network accessed from a mobile terminal
through a radio line is characterized in that a mobile management node arranged on
a corc nctwork side in order to perform ~nanageinentc ontrol of mobile
2 5 communication omits detach processing of the core network side in receiving a
detach request signal that requests detach from the mobile terminal, releases the
radio line in a state of holding as it is a co~nmunications ession of the core network
side set in the mobile terminal previously having attached, after that, omits attach
processing of the corc network side in receiving an attach request signal that
30 requests attach from the mobile terminal, uses as it is the communication session
of the core network side held regarding the mobile terminal, and sets the radio line.
[OOll]
(2) A communication control method according to the present invention is a
mobile terminal attachldetach processing method in a case where requests of attach
4
and detach are made fro111 a nlobile terminal to a core network in a mobile
communication network system provided with the eore network accessed from the
mobile terminal through a radio line, and the communication control method is
characterized in that a mobile management node arranged on a core network side in
5 order to perform management control of mobile communication ornits detach
processing of the core network side in receiving a detach request signal that
requests detach from the mobile terminal, releases the radio line in a state of
holding as it is a communication session of the core network side set in the mobile
terminal previously having attached, after that, omits attach processing of the core
10 network side in receiving an attach request signal that requests attach from the
mobile terminal, uses as it is the communication session of the core network side
held regarding the mobile terminal, and sets the radio line.
[O012]
(3) A communication control program according to the present invention is
15 characterized by carrying out at least the cornlnunication control method described
in the above (2) as a program executable by a computer with which the mobile
management node is provided.
Advantageous Effects of Invention
20 [0013]
According to the mobile communication network system, the mobile
terminal attachldetach processing method, and the mobile terminal attachldetach
processing program of the present invention, the following effects can be exerted.
[00 141
2 5 Namely, since the present invention makes it possible to omit the
attachldetach processing of the mobile terminal on the core network side
depending on terminal information and subscriber information that indicate
attributes of the mobile terminal, or a parameter added in addition to the
attachldetach request signal, it becomes possible to decrease the load of the eore
30 network side even in a case where a large amount of mobile terminals are
contained.
Brief Description of Drawings
[00 151
5
Fig. 1 is a system configuration diagram showing one example of the
system configurations of the mobile coillmunication network system according to
the present invention;
Fig. 2 is a system configuration diagram showing another example of the
5 system configurations of the mobile communication network system according to
the present invention;
Fig. 3 is a sequence chart showing one example of operation in a case of
carrying out usual attach processing;
Fig. 4 is a sequence chart showing one example of operation in a case of
10 omitting usual detach processing of the core network side when a detach request
signal is sent from the mobile station MS in the mobile communication network
system of Fig. 1;
Fig. 5 is a sequence chart showing one example of operation in a case of
omitting usual attach processing of the core network side when an attach request
15 signal is sent from mobile station MS after omission of the detach processing of
Fig. 4 in the mobile communication;
Fig.6A is a sequence chart showing one example of operation in a case of
carrying out usual attach processing based on a request signal from the mobile
station 1JE in the mobile communication network system of Fig. 1;
2 0 Fig.6B is a sequence chart showing one example of operation in a case of
carrying out usual attach processing based on a request signal from the mobile
station UE in the mobile communication network system of Fig. 1;
Fig. 7 is a sequence chart showing one example of operation in a case of
omitting usual detach processing of the tore network side when a detach request
2 5 signal is sent from the nlobile station UE in the mobile communication network
system of Fig. 2;
Fig.8A is sequence charts showing one example of operation in a case of
omitting usual attach processing of the core network side when an attach request
signal is sent from the mobile station UE after omission of the detach processing of
30 Fig. 7 in the mobile comillunication network system of Fig. 2;
Fig.8B is sequence charts showing one example of operation in a case of
omitting usual attach processing of the core network side when an attach request
signal is sent from the mobile station UE after omission of the detach processing of
Fig. 7 in the mobile con~n~unicationnet work system of Fig. 2;
Fig.9A is a sequence chart showing one cxanlple of operation in a case of
omitting usual dctach processing of the core network side when a detach request
signal is sent from the mobile station UE in the mobile comn~unicationn etwork
system of Fig. 2, the example being different from Fig. 7;
5 Fig.9B is a sequence chart showing one example of operation in a case of
omitting usual detach processing of the core network side when a detach request
signal is sent from the mobile station UE in the mobile coinmunication network
system of Fig. 2, the example being different from Fig. 7;
Fig.lOA is sequence charts showing one example of operation in a case of
10 omitting usual attach processing of the core network side when an attach request
signal is sent from the mobile station UE after omission of the detach processing of
Fig. 9 in the mobile communication network system of Fig. 2; and
Fig.lOB is sequence charts showing one example of operation in a case of
omitting usual attach processing of the core network side when an attach request
15 signal is sent from the mobile station UE after omission of the detach processing of
Fig. 9 in the mobile communication network system of Fig. 2.
Description of Embodiments
[00 161
2 0 Hereinafter, with reference to accompanying drawings, will be explained
preferred embodiments of a mobile communication network system, a mobile
terminal attachldetach processing method, and a mobile terminal attachldetach
processing program according to the present invention. Note, although in the
following explanation, explained are the nlobile co~nnlunicationn etwork system
2 5 and the mobile terminal attachldetach processing method according to the present
invention, it is needless to say that such mobile terminal attachldetach processing
method may be carried out as the mobile terminal attachldetach processing
program executable by a computer provided at a mobile management node
arranged on a core network side in order to performmanagement control of mobile
30 communication, or that the mobile terminal attachldetach processing program may
be recorded in a recording medium readable by the computer.
[00 171
(Features of Invention)
Prior to explanation of embodiments of the present invention, a summary of
features of the present invention will be explained first. The present inveiltion is
mainly characterized in that in the niobile inanagenient node arranged on the core
network side in order to perform management control of the mobile
communication, for example, in a niobile management node MME (Mobility
5 Management Entity) and a packet switch SGSN (Serving GPRS Support Node) that
have been specified in a 3GPP (Third Generation Partnership Project) standard,
detach processing of the core network side is not performed at the time of first
detach of a inobile terminal, thereby a session state of the core network side at the
time of first attach is held as it is on the core network side, attachldetach
10 processing of the core network side after the first attach can be omitted, thus attach
processing and detach processing of the core network side can be avoided from
being repeated with respect to a mobile terminal that repeats only attach and
detach, and that a load of the core network side can be decreased.
[OO 181
15 (Configuration examples of embodiment)
Next, using Figs. 1 and 2, will be explained one example of system
configuration examples of the mobile communication network system according to
the present invention. Fig. 1 is a system configuration diagram showing one
example of the system configurations of the mobile communication network
2 0 system according to the present invention, and shows a configuration example of a
mobile communication network system of a UTRAN (UMTS (Universal Mobile
Telephone Services) Terrestrial Radio Access Network)) scheme of a 3GPP
standard. In addition, Fig. 2 is a system configuration diagram showing another
example of the system configurations of the mobile communication network
2 5 system according to the present invention, and shows a configuration examplc of a
inobile communication network system of an E-UTRAN (Evolved UTRAN) scheine
of the 3GPP standard.
[0019]
The mobile comn~unicationn etwork system of the UTRAN scheme shown
30 in Fig. 1 is, as specified in the 3GPP (Third Generation Partnership Project)
standard, configured to include at least: a subscriber information management
device I-ILR (Home Location Registcr) 11; a subscriber location register VLR
(Visitor Location Register) 12; a packet switch SGSN (Serving GPRS (General
Packet Radio Service) Support Node) 13; a gateway packet switch GGSN (Gateway
GPRS Support Node) 14; a radio line control station RNC (Radio Network
Controller) 15; and a mobile station MS (Mobile Station) 16.
[0020]
I-Iere, in the embodiment, the packet switch SGSN 13 is a mobile
5 management node arranged on the core network side in order to connect the radio
line control station RNC 15 and to perfor111 management control of mobile
comniunication. The packet switch SGSN 13 can determine whether to reduce
attachldetach processing by means of terminal information and subscriber
information (a terminal type) that indicate attributes of a mobile terminal that
10 requests attachldetach, i.e., the mobile station MS 16, or a parameter etc. that are
added to an attachldetach request signal from the mobile terminal, i.e., the mobile
station MS 16. The packet switch SGSN 13 is provided with a function to omit
usual attachldetach processing of the core network side and to return a response
signal to the request signal with respect to the mobile terminal, i s . , the mobile
15 station MS 16, if determining that the mobile station MS 16 is the mobile terniinal
for which the attachldetach processing should be reduced.
[0021]
In addition, the mobile communication network system of the E-UTRAN
scheme shown in Fig. 2 is, as specified in the 3GPP standard, configured to include
2 0 at least: a subscriber information management device IlSS (Ilome Subscriber
Server) 21; a lnobile management node MME (Mobility Management Entity) 22; a
subscriber policylcharging rule management device PCRF (Policy and Charging
Rules Function) 23; a PDN gateway device P-GW (PDN (Packet Data Network)
Gateway) 24; a relay gateway device S-GW (Serving Gateway) 25; a radio base
2 5 station cNodeB (Enhanced Node B) 26; and a niobile station UE (User l~quipment)
27.
[0022]
Here, in the embodiment. the mobile management node MME 22 is a mobile
management node arranged on the core network side in order to connect the radio
30 base station eNodeB 26 and to perform management control of mobile
communication. The lnobile managemcnt node MME 22 can determine whether to
reduce attachldetach processing by means of terminal infornlation and subscriber
information (a terminal type) that indicate attributes of a mobile terniinal that
requests attachldetach, i.e., the mobile station UE 27, or a parameter etc. that are
added to an attacl~ldetachr equest signal from the nlobile terminal, i.e., the nlobile
station UE 27. The mobile management node MME 22 is provided with a
function to onlit usual attachldetach processing of the core network side and to
return a response signal to the request signal with respect to the mobile terminal,
5 i.e., the mobile station UE 27, if determining that the mobilc station UE 27 is the
mobile terminal for which the attachldetach processing should be reduced.
[0023]
(Explanation of operation of embodiment)
(First operation example)
10 Next, using sequence charts of Figs. 3 to 5, will be explained one example
of operation of the mobile communication network system of the UTRAN scheme
shown in Fig. 1. Fig. 3 is a sequence chart showing one example of operation in a
case of carrying out usual attach processing based on a request signal from the
mobile station MS 16 in the mobile communication network system of Fig. 1.
15 Fig. 4 is a sequence chart showing one example of operation in a case of omitting
usual detach processing of the core network side when a detach request signal is
sent from the mobile station MS 16 in the mobile communication network system
of Fig. 1. Fig. 5 is a sequence chart showing one example of operation in a case
of omitting usual attach processing of the core network side when an attach request
20 signal is sent from mobile station MS 16 after omission of the detach processing of
Fig. 4 in the mobile communication network system of Fig. I .
[0024]
First, using thc sequence chart shown in Fig. 3, will be explained a
procedure of executing usual attach processing based on a TS23.060 standard of
2 5 the 3GP1'. When receiving an Attach Request signal (attach request signal) that
requests attach from the mobile station MS 16 (sequence Seq I), the packet switch
SGSN 13 carries out security processing, such as authentication as the core
network regarding the mobile station MS 16 as a request source, secret processing,
and integrity (sequence Seq 2).
30 [0025]
When completing the security processing, such as authentication, secret
processing, and integrity, in a case of first registering the mobile station MS 16 as
the request source, the packet switch SGSN 13 sends an Update Location Request
signal that requests update registration of a location of the mobile station MS 16 to
the subscriber information ~nanagementd evice I-ILR 11 (sequence Seq 3). The
subscriber infor~nationm anagenlent device HLR 11 that has received the Update
Location Request signal performs the update registration of the location of the
mobile station MS 16 included in the Update Location Request signal, and sends
5 back to the packet switch SGSN 13 the terminal information and the subscriber
information that indicate the attributes regarding the mobile station MS 16 as an
Insert Subscriber Data signal (sequence Seq 4).
[0026]
The packet switch SGSN 13 confirms whether or not the mobile station MS
10 16 as the request source is the mobile station allowed to perform attach based on
the terminal information and the subscriber information that are included in the
received Insert Subscriber Data signal. When getting confirmation, the packet
switch SGSN 13 sends back to the subscriber information management device NLR
11 an Insert Subscriber Data Ack signal that indicates that the Insert Subscriber
15 Data signal has been normally received together with an MM (Mobility
Management) context that indicates a confirmation result (sequence Seq 5). The
subscriber informatioil management device HLR 11 that has received the Insert
Subscriber Data Ack signal registers the MM context that indicates the
confirmation result, and sends to the packet switch SGSN 13 an Update Location
2 0 Answer signal that indicates that a request of the Update Location Request signal.
has been accepted (sequence Seq 6).
[0027]
After that, the packet switch SGSN 13 sends to the subscriber location
register VLR 12 a Location Update Request signal that requests the update
25 registration of the location of the mobile station MS 16 (sequence Seq 7). The
subscriber location register VLR 12 that has received the Location Update Request
signal performs the update registration of the locatioil of the mobile station MS 16,
and sends an Update Location signal to the subscriber information management
device I-ILR 11 in order to perform association (sequence Seq 8).
30 LO0281
The subscriber information management device HLR 11 that has received
the Update Location signal sends back to the subscriber location register VLR 12
the terminal information and the subscriber information that indicate the attributes
regarding the mobilc station MS 16 (sequence Seq 9). When receiving the lnsert
Subscriber Data signal, the subscriber location register VLR 12 registers the
terminal information and the subscriber information regarding the mobile station
MS 16, and sends back to the subscriber information management device I-ILR 11
the Insert Subscriber Data Ack signal that indicates that the Insert Subscriber Data
5 signal has been normally received (sequence Seq 10).
[0029]
The subscriber information management device HLR 11 that has received
the Insert Subscriber Data Ack signal sends to the subscriber location register VLR
12 an Update Location Ack signal that indicates that a request of the Update
10 Location signal has been accepted (sequence Seq 11). The subscriber location
register VLR 12 that has received the Update Location Ack signal acquires a
temporary mobile station identifier TMSI (Temporary Mobile Subscriber Identity)
for specifying the mobile station MS 16, and sends back to the packet switch SGSN
13 as a transmission source of the Location Update Request signal a Location
15 Update Accept signal that includes the temporary mobile station identifier TMSI
and indicates that the association regarding the location update of the mobile
station MS 16 has been ended (sequence Seq 12).
[0030]
The packet switch SGSN 13 that has received the Location Update Accept
20 signal sends to the mobile station MS 16 as the request source an Attach Accept
signal that indicates that the attach processing requested from the mobile station
MS 16 has been completed (sequence Seq 13). After that, when receiving an
Attach Complete signal that indicates that the Attach Accept signal has been
received from the mobile station MS 16 (sequence Seq 14), the packet switch
25 SGSN 13 sends back a TMSI Reallocation Complete signal that indicates that
rearrangement of the temporary mobile station identifier TMSI has been completed
to the subscriber location register VLR 12 to which the temporary mobile station
identifier TMSI has been allocated (sequence Seq 15).
[003 11
3 0 When the attach processing of mobile station MS 16 to the core network
side has been completed by means of the above procedure, the mobile station MS
16 transmits to the packet switch SGSN 13 an Activate PDP Context Request signal
that requests PDP (Packet Data Protocol) context activation for pcrforming
communication with a con~municationp artner (sequence Seq 16). Information,
such as a I'DI' type that indicates a type of communication, a PDP address that
indicates the commullicatioll partner, an access point name, requested service
quality, is included in the Activate PDP Context Request signal.
100321
5 Based on the received Activate PDP Context Request signal, the packet
switch SGSN 13 selects an access point to map in the gateway packet switch GGSN
14, and generates a Create PDP Context Request signal to send to the gateway
packet switch GGSN 14 (sequence Seq 17). The gateway packet switch GGSN 14
that has received the Create PDP Context Request signal generates a new entry in a
10 PDP context table, and sends back to the packet switch SGSN 13 a Create PDP
Context Response signal that indicates that the new entry has been generated in the
PDP context table (sequence Seq 18).
[0033]
As a result of this, setup of a radio access bearer (Radio Access Bearer
15 Setup) is executed among the mobile station MS 16, the radio line control station
RNC 15, and the packet switch SGSN 13 (sequence Seq 19). When setup of the
radio access bearer is ended, and a communication session is established, the
packet switch SGSN 13 sends back to the mobile station MS 16 an Activate PDP
Context Accept signal that indicates that the PDP context activation has been
2 0 ended (sequence Seq 20).
[0034]
As described above, when in the packet switch SGSN 13 that has received a
usual attach request from the mobile terminal, i.e., the mobile station MS 16, the
usual attach processitlg is carried out and the con~munications ession of the mobile
25 terminal, i.e., the mobile station MS 16, is established, the packet switch SGSN 13
becomes a state of holding the established session.
100351
Next, using a sequence chart of Fig. 4, will be explained one example of
operation in a case of omitting usual detach processing of the core network side
30 when a detach request is generated from the mobile station MS 16 in a state where
the attach processing has been executed in Fig. 3. First, will be explained a
sequence in a case of carrying out the usual detach processing when the detach
request is generated.
100361
When the usual detach processing is carried out, the packet switch SGSN
13 receives a Detach Request signal (detach request signal) that requests detach
from the mobile station MS 16 (sequence Seq 31). Next, in order to release a
communication session with a communication partner, the packet switch SGSN 13
5 generates a Delete PDP Context Request signal, and sends it to the gateway packet
switch GGSN 14 (sequence Seq 32).
100371
The gateway packet switch GGSN 14 that has received the Delete PDP
Context Request signal deletes an appropriate entry from the PDP context table,
10 and sends back to the packet switch SGSN 13 a Delete PDP Context Response
signal that indicates that the session has been released (sequence Seq 33). When
receiving the Delete PDP Context Response signal, the packet switch SGSN 13
sends a GPRS (General Packet Radio Service) Detach Indication signal to the
subscriber location register VLR 12 to which the temporary mobile station
15 identifier TMSI for the communication has been allocated. The packet switch
SGSN 13 hereby releases allocation of the temporary mobile station identifier
TMSI, and makes association with the packet switch SGSN 13 deleted (sequence
Seq 34).
[0038]
2 0 When the above detach processing of the core network side is ended, the
packet switch SGSN 13 sends to the mobile station MS 16 as the request source a
Detach Accept signal that indicates that the detach processing requested from the
mobile station MS 16 has been completed (sequence Seq 35). As a result of this,
the packet switch SGSN 13 transitions to a state of PS Signalling Connection
2 5 Release, radio resources between the lnobile station MS 16 and the radio line
control station RNC 15 are released, and connection of a signal for packet service
of the mobile station MS 16 with the core network side is opened (sequence Seq
36).
100391
3 0 Next, using the sequence chart of Fig. 4, will be explained operation in the
case of omitting the usual detach processing of the core network side, even though
the detach request is generated from the mobile station MS 16 in the embodinlent
according to the present invention.
[0040]
In the case of omitting the usual dctach processing of the core network
side, when as shown in Fig. 4, receiving the Detach Request signal (detach requcst
signal) that requests detach from the mobile terminal, i.e., the mobile station MS
16 (sequence Seq 31), the packet switch SGSN 13 determines whether or not the
5 mobile terminal, i.e., the mobile station MS 16 is the mobile terminal as a target of
attachldetach processing reduction by referring to the terminal information or the
subscriber information etc. in which the attributes of the mobile terminal have
been registered.
[0041]
10 As a result of it, if the packet switch SGSN 13 determines that the mobile
terminal, i.e., the mobile station MS 16, is the mobile terminal as the target of the
attachldetach processing reduction, detach processing of the core network side of
sequences Seq 32, Seq 33, and Seq 34 is omitted, and processing proceeds to
sequence Seq 35, remaining in a state of holding the communication session
15 (Session) in the network. The packet switch SGSN 13 then sends the Detach
Accept signal to the mobile station MS 16 as the request source, remaining in a
state where the detach processing of the core network side has not been carried out
(sequence Seq 35).
[0042]
2 0 Accordingly, also after that, in the core network side including the packet
switch SGSN 13, only a radio block transitions to the state of PS Signalling
Connection Release, with session information of the mobile terminal, i.e., the
mobile station MS 16 being continued to be field, radio resources between the
mobile station MS 16 and the radio line control station RNC 15 are released, and
25 connection of the signal for the packet service of the nlobile station MS 16 with the
core network side is opened (sequence Seq 36). That is, as for the radio resources
between the mobile station MS 16 and the radio line control station RNC 15,
establishment/release is certainly carried out in each time of attachldetach
processing regardless of omission of the detach processing of the core network
30 side.
[0043]
It is to be noted that when only the radio block for accessing the core
network transitions to the state of PS Signalling Connection Release, remaining in
the state of holding the com~llunications ession (Session) in the core network side,
the packet switch SGSN 13 performs the following setting in order to prevent a
release failure of the con~nlunications ession of the network side. For example, in
sequence Seq 35, the packet switch SGSN 13 sets to a session holding timer a time
a little longer by a predetermined time than a generation interval of a
5 reattachlredetach request from the mobile terminal, i.e., thc mobile station MS 16,
as a time to wait for forced release of the session.
100441
After that, when the session holding timer expires, for example, when the
reattachlredetach request from the mobile terminal, i.e., the mobile station MS 16,
10 is not generated once a day, the packet switch SGSN 13 carries out the usual detach
processing of sequences Seq 32, Seq 33, and Seq 34. Hereby deleted is
information on the communication session of the mobile station MS 16 that has
been held in not only the packet switch SGSN 13 but in the gateway packet switch
GGSN 14 and the subscriber location register VLR 12, and the session in the
15 packet switch SGSN 13 etc. is released.
[0045]
Furthermore, when sending the Detach Accept signal to the mobile station
MS 16 as the request source, with the detach processing of the core nctwork side
not being carried out, the packet switch SGSN 13 stops a periodic RAU (Routing
2 0 Area Update) waiting timer that is the timer for periodically updating a routing
area and also cancels a subsequent paging request until a reattach request from the
mobile station MS 16 is generated or the session holding timer expires.
[0046]
Next, using a sequence chart of Fig. 5 , will be explained one examplc of
2 5 operation in a case of omitting the usual attach processing of the core network side
when an attach request is generated from the mobile station MS 16 in a state where
the detach processing is omitted in Fig. 4. When the attach request is generated
from the mobile station MS 16, usually, attach processing as illustrated in Fig. 3 is
carried out. However, when the attach request from the mobile station MS 16 is
30 generated in the state where the detach processing is omitted, as shown in Fig. 5 ,
the usual attach processing of the core nctwork side is omitted, and sequences Seq
3 to Seq 12, sequence Seq 15, sequcnccs Seq 17 and 18 are omitted.
100471
Here, the mobile terminal, i.e., the mobile station MS 16, holds an old
Security context allocated at the time of the previous attach processing. and
transmits the Attach Request signal (attach request signal) using the held old
Security context to the packet switch SGSN 13 (sequence Seq 1).
[0048]
5 When receiving the Attach Request signal using the old Security context
from the mobile station MS 16, the pacltet switch SGSN 13 determines whether or
not the mobile station MS 16 is the mobile terminal for which the detach
processing to the communication session in having performed the attach
processing previous time was omitted as a result of analyzing the Attach Request
10 signal. If determining that the Attach Request signal is a reattach request from
the mobile station MS 16 for which the detach processing was omitted, the packet
switch SGSN 13 omits to carry out security processing, such as authentication as
the core network regarding the mobile station MS 16 as the request source, secret
processing, and integrity, and continues to use the old Security context as it is
15 (sequence Seq 2).
[0049]
Furthermore, the packet switch SGSN 13 omits the attach processing of the
core network side of sequences Seq 3 to Seq 12, and sends to the mobile station
MS 16 as the request source an Attach Accept signal that indicates that the reattach
2 0 processing requested from the mobile station MS 16 has been completed (sequence
Seq 13). After that, when receiving the Attach Complete signal that indicates that
the Attach Accept signal has been received from the mobile station MS 16
(sequence Seq 14), the packet switch SGSN 13 also omits operation of sequence
Seq 15 that sends back a TMSI Reallocation Complete signal to the subscriber
2 5 location register VLR 12, and transitio~lst o a state of waiting an Activate PDP
Context Request signal from the mobile station MS 16.
[OOSO]
When receiving the Activate PDP Context Request signal from the mobile
station MS 16, the Packet switch SGSN 13 also omits operation of sequences Seq
30 17 and Seq 18 that exchanges the Create PDI' Context Request signal and the
Create PDP Context Request signal with the gateway packet switch GGSN 14, and
executes the setup of a radio access bearer (Radio Access Bearer Setup) among the
mobile station MS 16, the radio line control station RNC 15, and the packet switch
SGSN 13 (sequence Seq 19). When the setup of the radio access bearer is ended,
and the com~l~unicatiosnes sion is established, the packet switch SGSN 13 sends
back to the mobile station MS 16 an Activate PDP Context Accept signal that
indicates that the PDP context activation has been ended (sequence Seq 20).
[0051]
5 As described above, the packet switch SGSN 13 that has received the usual
attach request from the mobile terminal, i.e., the mobile station MS 16 becon~esa
state of performing communication using the communication session held previous
time as it is without carrying out the usual attach processing of the core network
side.
10 [0052]
It is to be noted that although in the above-mentioned operation example,
has been explained the case where the information is used that indicates the
attributes of the terminal, such as the terminal information and the subscriber
information of the mobile terminal, i.e., the mobile station MS 16, at the time of
15 the detachlattach request, as information to determine whether or not the mobile
terminal, i.e., the mobile station MS 16 is the mobile terminal as the target of the
attachldetach processing reduction in the packet switch SGSN 13, the present
invention is not limited to such case.
[0053]
2 0 For example, to the detachtattach request signal, may be added a parameter
(for example, sleep notification that indicates that a power source of the mobile
station MS 16 transitions to a sleep state at the time of detach, and wake up
notification that indicates that the power source of the mobile station MS 16 has
transitioned to a wake up state from the sleep state at the time of attach) that
25 indicates whether or not the mobile station MS 16 is the mobile terminal as the
target of the attachldetach processing reduction. Iiereby, in receiving the
detachlattach request signal, the packet switch SGSN 13 may determine whether or
not the mobile terminal, i.e., the mobile station MS 16, is the mobile terminal as
the target of the attachldetach processing reduction by referring to such parameter
30 added in addition to the detachlattach request signal.
[0054]
(Second operation example)
Next, using sequence charts of Figs. 6 to 8, will be explained one example
of operation of the mobile communication network system of the E-UTRAN
scheme shown in Fig. 2. Just similarly not only in the case of the nlobile
commu~~icationne twork system of the UTRAN scheme of Fig. 1 but also in the
mobile com~llunicationn etwork system of the E-UTRAN scheme of Fig. 2, it is
possible to reduce the attachtdetach processing of the core network (core node)
5 side. Figs. 6A and 6B are sequence charts showing one example of operation in a
case of carrying out usual attach processing based on a request signal from the
mobile station UE 27 in the mobile communication network system of Fig. 2.
Fig. 7 is a sequence chart showing one example of operation in a case of omitting
usual detach processing of the core network side whcn a dctach request signal is
10 sent from the mobile station UE 27 in the mobile communication network system
of Fig. 2. Figs. 8A and 8B are sequence charts showing one example of operation
in a case of omitting usual attach processing of the core network side when an
attach request signal is sent from the mobile station UE 27 after omission of the
detach processing of Fig. 7 in the mobile communication network system of Fig. 2.
15 [0055]
First, using the sequence charts shown in Figs. 6A and 6B, will be
explained a procedure of executing usual attach processing based on a TS23.401
standard of the 3GPP. The mobile station UE 27 sets a radio control link through
which a control signal is transmitted and received to and from the radio base
20 station eNodeB 26, and sends an EMM (EPS (Evolved Packet System) Mobility
Management) Attach Request signal (attach request signal) that requests attach to
the mobile management node MME 22 (sequence Seq 41). The radio base station
eNodeB 26 that has received the EMM Attach Request signal selects the mobile
management node MME 22 that serves as a transn~issiond estination, and sends an
2 5 EMM Attach Request signal of an S 1 -AP (S 1 Application Protoco1)~Iuitial UE
Message form to the selected mobile management node MME 22 (sequence Seq
42).
[0056]
When receiving the EMM Attach Request signal that requests attach from
30 the mobile station UE 27, the mobile management node MME 22 carries out
authentication processing as a core network regarding the mobile station UE 27 as
a request source (sequence Seq 43). When the authentication processing is ended,
thc mobile management node MME 22 carries out security processing, such as
secret processing regarding an NAS (Non-Access-Stratum) among the mobile
station UE 27, thc radio base station eNodeB 26, and the lnobile tnanage~l~cnot de
MME 22, and integrity (sequence Seq 44).
lo0571
When completing the security processing, such as secret processing and
5 integrity, in a case of first registering the mobile station IJE 27 as the request
source, the mobile management node MME 22 sends to a subscriber information
management device HSS 21 a Diameter Update Location Request signal that
requests update registration of a location of the mobile station UE 27 (sequence
Seq 45). When the subscriber information management device IlSS 21 that has
10 received the Diameter Update Location Request signal confirms presencelabsence
of an LTE (Long Term Evolution) agreement of the mobile station UE 27 included
in the Diameter Update Location Request signal, and when the agreement is made,
the subscriber information management device HSS 21 performs update
registration of the location of the mobile station UE 27, and sends back to the
15 mobile management node MME 22 a Diameter Update Location Answer signal that
indicates that registration of the location of the mobile station UE 27 has been
completed (sequence Seq 46).
[0058]
The mobile management node MME 22 selects the relay gateway device
20 S-GW 25 that relays packet data transmitted and received tolfrom the mobile
station UE 27 through the radio base station eNodeB 26. Furthermore, the mobile
management node MME 22 selects a PDN gateway device P-GW 24 that transfers
packet data between the relay gateway device S-GW 25 and a default PDN (Packet
Data Network) previously allocated to the mobile station UE 27. Furthermore,
2 5 the mobile management node MME 22 derives a bearer for transferring packet data
set as a default based on a modelln~anufacturer identification code TAC (Type
Allocation Code) included in an identification number IMEI (International Mobile
Equipment Identity) of the mobile station UE 27 (sequence Seq 47).
[0059]
3 0 After that, the mobile management node MME 22 sends to the selected
relay gateway device S-GW 25 a GTPv2 (Evolved GPRS (General Packet Radio
Service) Tunneling Protocol for EPS (Evolved Packet System)) Create Session
Request signal that serves as a setting request of the bearer of the packet data
between the mobile station UE 27 and the default PDN (sequence Seq 48). In the
GTPv2 Create Session Request signal, included are at least the identification
number IMEI of the mobile station UE 27, an 1P address of the selected PDN
gateway device P-GW 24, and a bearer to be set.
[0060]
5 The relay gateway device S-GW 25 that has received the GTPv2 Create
Session Requcst signal sets a communication session of the designated mobile
station UE 27, and sends to the subscriber policylcharging rule management device
PCRF 23 a Diameter CC-Request signal for inquiring a charging rule and a policy
of communication quality regarding conlmunication of the designated mobile
10 station UE 27 (sequence Seq 49). The subscriber policylcharging rule
management device PCRF 23 that has received the Diameter CC-Request signal
sets the communication session of the mobile station UE 27, and sends back to the
relay gateway device S-GW 25 as an inquirer information including the charging
rule and the policy of the communication quality regarding the communication of
15 the mobile station UE 27 as a Diameter CC-Answer signal (sequence Seq 50).
[0061]
When receiving the Diameter CC-Answer signal, the relay gateway device
S-GW 25 performs setting of information on the charging rule, the policy of the
communication quality, and a trigger of an event regarding the communication of
20 the mobile station UE 27, and the designated bearer. Furthermore, the relay
gateway device S-GW 25 sends a PMIPv6 (Proxy Mobile IPv6) Proxy Binding
Update signal that requests binding path setting to the PDN gateway device P-GW
24 in order to set a tunneling path with the designated PDN gateway device P-GW
24 (sequence Seq 51).
25 [0062]
The PDN gateway device P-GW 24 that has received the PMIPv6 Proxy
Binding Update signal allocates an IP address for the mobile station MS 16 in the
default PDN and secures the designated bearer, and sends to the subscriber
policylcharging rule management device PCRF 23 the Diameter CC-Request signal
30 that requests decision of the charging rule and the policy of the communication
quality regarding the colll~nunicationo f the mobile station UE 27 (sequence Seq
52). Thc subscriber policy/charging rule management device PCRF 23 that has
received the Diamcter CC-Request signal decides the charging rule and the policy
of the communication quality regarding the communication of the mobile station
UE 27 based on thc comn~unicationp ath and the bearer that have been secured as
the mobile station UE 27, and sends back them to the PDN gateway device P-GW
24 as the Diameter CC-Answer signal (sequence Seq 53).
[0063]
5 When receiving the Diameter CC-Answer signal, the I'DN gateway device
P-GW 24 allocates the IP address for the mobile station MS 16 in the default PDN.
Furthern~oret,h e PDN gateway device P-GW 24 sets a tunneling path of the
designated bearer, and subsequently, sends back to the relay gateway device S-GW
25 a PMIPv6 Proxy Binding Acknowledge~nent signal that indicates that the
10 tunneling path of the designated bearer has been set (sequence Seq 54). As a
result of this, the always held tunneling path is set to the allocated IP address as a
communication session between the PDN gateway device P-GW 24 and the relay
gateway device S-GW 25.
[0064]
1 5 The relay gateway device S-GW 25 that has received the PMIPv6 Proxy
Binding Acknowledgement signal prepares a radio access bearer that goes in a
direction from the relay gateway device S-GW 25 to the radio base station eNodeB
26, and sends back to the mobile management node MME 22 a GTPv2 Create
Session Answer signal that indicates that setting of the bearer of the packet data
20 has been completed (sequence Seq 55).
[0065]
The mobile management node MME 22 that has received the GTPv2 Create
Session Answer signal indicates that the attach processing requested from the
mobile station UE 27 has been completed, and sends to the radio basc station
25 cNodcB 26 an EMM Attach Accept signal of an S1-AP-Initial Context Setup
Request form that requests setting of a context including contents required for a
communication path and commu~~icatiocno ntrol, such as an IP address, a bearer,
and a policy regarding quality, that are included in the GTPv2 Create Session
Answer signal (sequence Seq 56).
30 100661
When receiving the EMM Attach Accept signal of the S1-AP-Initial
Context Setup Requcst form, the radio base station eNodeB 26 carries out security
processing, such as secret processing regarding an AS (Access-Stratum) in a radio
block with the mobile station IJE 27, and integrity (sequence Seq 57). The radio
base station eNodeB 26 indicates cotnpletion of the attach processing of the core
network side, and sends to the mobile station IJE 27 as the request source an RRC
(Radio Resource Control) Connection Reconfiguration signal that instructs setting
of the contents required for the comn~unicationp ath and the comnlunication
5 control, such as the IP address, the bearer, and the policy regarding the quality,
that are included in the EMM Attach Accept signal (sequence Seq 58).
[0067]
The mobile station UE 27 sets a priority (Radio Priority) of a radio signal,
etc. based on the contents included in the RRC Connection Reconfiguration signal.
10 Furthermore, the mobile station UE 27 stores a packet flow identification ID
(Packet Flow Id), the IP address, the bearer, the policy of the quality (i.e., QoS
(Quality of Service) Ncgotiation), etc. Furthermore, the mobile station UE 27
sends back to the radio base station eNodeB 26 an RRC Connection Complete
signal that indicates that the setting instructed by the RRC Connection
15 Reconfiguration signal has been ended (sequence Seq 59).
[0068]
The radio base station eNodeB 26 that has received the RRC Connection
Complete signal sends back to the mobile management node MME 22 an
S1 -AP-Initial Context Setup Response signal that indicates that setting in
20 accordance with contents instructed as an S1-AP-Initial Context Setup Request
signal has been completed (sequence Seq 60). Information that the radio base
station eNodeB 26 has set is also included in the S1-AP-Initial Context Setup
Response signal as information required for setting of the radio access bearer that
goes in the direction from the relay gateway device S-GW 25 to the radio base
25 station eNodeB 26.
[0069]
After that, when receiving from the mobile station UE 27 information
(Uplink Information) on an uplink direction of the radio line that goes to a radio
base station eNodeB 26 side as an RRC UL Information Transfer signal (sequence
30 Seq 61), the radio base station eNodeB 26 generates an EMM Attach Complete
signal that indicates that the attach processing has been completed, and sends it to
the mobile management node MME 22 (sequence Seq 62). The mobile
managcment node MME 22 that has received the EMM Attach Complete signal
sends an EMM Information signal to the mobile station UE 27 through the radio
base station eNodcB 26 (sequence Seq 63).
[0070]
As described above, when in the mobile ~nanagemcntn ode MME 22 that
has received the usual attach request from the mobile terminal, i.e., the mobile
5 station UE 27. the usual attach processing is carried out and the coinmunication
session of the mobile terminal, i.e., the mobile station UE 27, is established, the
mobile management node MME 22 becomes a state of holding the established
session.
[0071]
10 Next, using a sequence chart of Fig. 7, will be explained one example of
operation in a case of omitting usual detach processing of the core network side
when a detach request is generated from the mobile station UE 27 in a state where
the attach processing has been executed in Fig. 6. First, will be explained a
sequence in a case of carrying out the usual detach processing when the detach
15 request is generated.
[0072]
When the usual detach processing is carried out, the mobile station UE 27
sets a radio control link through which a control signal is transmitted and received
totfrom the radio base station eNodeB 26, and sends to the radio base station
20 eNodeB 26 an EMM Detach Request signal (detach request signal) that requests
detach for the mobile management node MME 22 (sequence Seq 71). The radio
base station eNodeB 26 that has received the EMM Detach Request signal sends to
the mobile management node MME 22 as a transmission destination an EMM
Detach Request signal of an S 1 -AP (S 1 Application Protocol)-Uplink NAS
25 Transport for111 (sequence Seq 72).
[0073]
The mobile management node MME 22 that has received the EMM Detach
Request signal sends a GTPv2 Delete Session Request signal that serves as a
release request of a session of packet data between the mobile station UE 27 and
30 the default PDN to the relay gateway device S-GW 25 that has formed the
communication session of the mobile station IJE 27 (sequence Seq 73). When
receiving the GTPv2 Delete Session Requcst signal, the relay gateway device
S-GW 25 releases a bearer used for the session, and subsequently, sends to the
subscriber policy/cbarging rule management device PCRF 23 a Diameter
CC-Requcst signal that rcquests to delete the conlmunication scssion (sequence
Seq 74).
[0074]
The subscriber policylcharging rule management device PCRF 23 that has
5 received the Diameter CC-Request signal deletes a session for gateway control
(Gateway Control Session) regarding the mobile station UE 27, and sends back to
the relay gateway device S-GW 25 as an inquirer a Diameter CC-Answer signal
that indicates that the session for gateway control has been deleted (sequence Seq
75).
10 [0075]
When receiving the Dialneter CC-Answer signal, the relay gateway devicc
S-GW 25 deletes the information on the charging rule, the policy of the
communication quality, and the trigger of the event regarding the communication
of the mobile station UE 27. Furthermore, the relay gateway device S-GW 25
15 sends a I'MIPv6 (Proxy Mobile IPv6) Proxy Binding Update signal that requests
release of the binding path setting to the PDN gateway device P-GW 24 in order to
open the tunneling path with the PDN gateway device P-GW 24 allocated to the
communication session of the mobile station UE 27 (sequence Seq 76).
[0076]
2 0 The PDN gateway device P-GW 24 that has received the PMIPv6 Proxy
Binding Update signal sends to the subscriber policylcharging rule management
device PCRF 23 a Diamcter CC-Request signal that requests deletion of a charging
rule and a policy of communication quality regarding a con~munications ession of
an IP-CAN (IP-Connectivity Access Network) of a bearer level of the mobile
2 5 station UE 27, and deletes all the charging rules and policics of the communication
quality regarding the mobile station UE 27 (sequence Seq 77).
[0077]
The Subscriber policy/charging rule management device PCRF 23 that has
received the Diameter CC-Request signal releases the communication session of
3 0 the IP-CAN regarding the communication of the bearer level of the mobile station
UE 27 and deletes all the registration information on the communication session of
the IP-CAN session, and sends back to the PDN gateway device P-GW 24 as a
Diameter CC-Answer signal (sequence Seq 78).
[0078]
When receiving the Diameter CC-Answer signal, the PDN gateway device
P-GW 24 opens the tunneling path of the set bearer, and subsequently, sends back
to the relay gateway device S-GW 25 a PMIPv6 Proxy Binding Acknowledgen~ent
signal that indicates that the tunneling path of the set bearer has been opened
5 (sequence Seq 79). As a result of this, the tunneling path always held between
the PDN gateway device P-GW 24 and the relay gateway device S-GW 25 is
opened.
[0079]
The relay gateway device S-GW 25 that has received the PMIPv6 Proxy
10 Binding Acknowledgement signal deletes setting of the radio access bearer that
goes in the direction from the relay gateway device S-GW 25 to the radio base
station eNodeB 26, and sends back to the mobile management node MME 22 a
GTPv2 Delete Session Answer signal that indicates that release of the bearer of the
packet data has been completed (sequence Seq 80).
15 [0080]
The mobile management node MME 22 that has received the GTPv2 Create
Session Answer signal indicates that the detach processing requested from the
mobile station UE 27 has been completed, and sends to the radio base station
eNodeB 26 an EMM Detach Accept signal of an S 1 -AP-Downlink NAS Transport
2 0 form including contents required for release of a communication path and
communication control that are included in the GTPv2 Create Session Answer
signal (sequence Seq 81). As a result of this, the core network side transitions to
a state of Signalling Connection Release, and becomes a state where all resources
regarding the communication session in which detach has been requested from the
25 mobile station UE 27 are released (sequence Seq 82).
loo8 11
When determining that the above detach processing of the core network
side has been ended by receiving the EMM Detach Accept signal, the radio base
station eNodeB 26 releases setting in the radio base station eNodeB 26 based on
30 information included in the EMM Detach Accept signal, and sends to the mobile
station UE 27 as the request source an EMM Detach Accept signal that indicates
that all the detach processing requested from the mobile station UE 27 has bcen
completed (scquence Seq 83). As a result of this, a wirclcss block also
transitions to the state of Signalling Connection Release, radio resources between
the mobile station UE 27 and the radio base station eNodeB 26 are released, and
conncction of a signal for packet service of the mobile station UE 27 with the core
network side is opened (sequence Seq 84).
[0082]
5 Next, using the sequence chart of Fig. 7, will be explained operation in the
case of omitting the usual detach processing of the core network side, even though
the detach request is generated from the mobile station IJE 27 in the embodiment
according to the present invention.
[0083]
10 In the case of omitting the usual detach processing of the core network
side, as shown in Fig. 7, the mobile management node MME 22 receives an EMM
Detach Request signal (detach request signal) that requests detach from the mobile
terminal, i.e., the mobile station UE 27 via the radio base station eNodeB 26
(sequence Seq 72). The mobile management node MME 22 determines whether or
15 not the mobile terminal, i.e., the mobile station UE 27 is the mobile terminal as a
target of attachldetach processing reduction by referring to terminal information or
subscriber information etc. in which attributes of the mobile terminal have been
registered.
[0084]
2 0 As a result of it, if the mobile management node MME 22 determines that
the mobile terminal, i.e., the mobile station UE 27, is the mobile terminal as the
target of the attachldetach processing reduction, detach processing of the core
network side of sequences Seq 73 to Seq 80 is omitted, and processing proceeds to
sequence Seq 81, remaining in a state of holding a comn~unications ession
2 5 (Session) in the network. The mobile management node MME 22 then sends an
EMM Detach Accept signal to the radio base station eNodeB 26 of which the
mobile station UE 27 as the request source is in a service area, remaining in a state
of not carrying out the detach processing of the core network side (sequence Seq
81). After that, the radio base station eNodeB 26 sends the EMM Detach Accept
30 signal to the mobile station UE 27 as the request source (sequence Seq 83).
[OOSS]
Accordingly, also after that, the core network side including the mobile
management node MME 22 does not transition to the state of Signalling
Connection Release of sequence Seq 82, and only a radio block for accessing the
core network transitions to the state of Sigrlalling Connection Release, with
session information of the mobile terminal, i.e., the mobilc station UE 27 being
continued to be held. In addition, radio resources between the mobile station UE
27 and the radio base station eNodeB 26 are released, and connectioil of the signal
5 for the packet service of the mobile station UE 27 with the core network side is
opened (sequence Scq 84). That is, as for the radio resources between the mobile
station UE 27 and the radio base station eNodeB 26, establishmentlrelease is
certainly carried out in each time of the attachldetach processing regardless of
omission of the detach processing of the core network side.
10 [0086]
It is to be noted that when only the radio block for accessing the core
network transitions to the state of Signalling Connection Release, remaining in the
state of holding the commullication session (Session) in the core network side, the
mobile management node MME 22 performs next setting in order to prevent a
15 release failure of the communication session of the network side. In sequence
Seq 81, the mobile management node MME 22 sets to a session holding timer a
time a little longer by a predetermined time than a generation interval of a
reattach/redetach request from the mobile terminal, i.e., the mobile station UE 27,
as a time to wait for forced release of the session.
20 [0087]
After that, when the session holding timer expires, for example, when the
reattachlredetach request from the mobile terminal, i.e., the mobile station UE 27,
is not generated once a day, the nlobile management node MME 22 carries out
usual detach processing of sequences Seq 73 to Seq 80. Hereby deleted is
25 information on the communicatioil session of the mobile station UE 27 that has
becn held in the core network side including the n~obilem anagement node MME
22, and the session is released.
[OOSS]
Furthermore, when sending the EMM Detach Accept signal to the radio
30 base station eNodeB 26 of which the mobile station UE 27 as the request source is
in the service area, with the detach processing of the core network side not being
carried out, the mobile management node MME 22 stops a periodic TAU (Tracking
Area Update) waiting timer that is the tiiner for periodically updating a location
registration area, and also cancels a subsequent paging request until a reattach
request from ihe mobile station UE 27 is generated, or the session holding timer
expires.
[0089]
Next, using sequence charts of Figs. 8A and 8B, will be explained one
5 example of operation in a case of omitting usual attach processing of the core
network side when an attach request is generated fsom the mobile station UE 27 in
the state where the detach processing is omitted in Fig. 7. When the attach
request is generated from the mobile station UE 27, usually, attach processing as
illustrated in Fig. 6 is carried out. However, when the attach request from the
10 mobile station UE 27 is generated in the state where the detach processing is
omitted, as shown in Fig. 8A, the usual attach processing of the core network side
is omitted, and processing of sequences Seq 45 to Seq 55 is omitted.
[0090]
Here, the mobile terminal, i.e., the mobile station UE 27, holds an old
15 Security context allocated at the time of the last attach processing, and transmits to
the radio base station eNodeB 26 an EMM Attach Request signal (attach request
signal) using the held old Security context (sequence Seq 41). Accordingly, the
radio base station eNodeR 26 sends to the mobile management node MME 22 the
EMM Attach Request signal using the old Security context (sequence Seq 42).
20 [0091]
When receiving the EMM Attach Request signal using the old Security
context that has been sent from the mobile station UE 27 through the radio base
station eNodeB 26, the mobile managemcnt node MME 22 determines whether or
not the mobile station UE 27 is the mobile terminal for which detach processing to
25 the comn~unications ession in having performed the attach processing previous
time was omitted as a result of analyzing the EMM Attach Request signal. If
determining that the EMM Attach Request signal is a reattach request from the
mobile station UE 27 for which the detach processing was omitted, the mobile
management node MME 22 omits to carry out security processing, such as
30 authentication as the core network regarding the mobile station UE 27 as the
request source, secret processing, and integrity, and continues to use the old
Security context as it is (sequences Seq 43 and Seq 44).
[00921
Furthermore, the mobile management node MME 22 omits attach
processing of the core network side of sequences Seq 45 to Seq 55, and sends to
the radio base station eNodeB 26 of which the nlobile station UE 27 as the request
source is in the service area an EMM Attach Accept signal of the Sl-AP - Initial
Context Setup Request form that indicates that reattach processing requested from
5 the mobile station UE 27 has been completed (sequence Seq 56). After that, after
carrying out setting processing of a radio line for accessing the core network with
respect to the mobile station UE 27 as the request source by a procedure similar to
the usual attach processing, the radio base station eNodeB 26 sends to the mobile
management node MME 22 from the radio base station eNodeB 26 an
10 S1-AP-Initial Context Setup Response signal that indicates that the EMM Attach
Accept signal of the S1-AP-Initial Context Setup Request form has been received
(sequence Seq 60).
[0093]
Furthermore, similarly to the case of the usual attach processing, when
15 receiving information (Uplink Information) on an uplink direction of the radio line
that goes to the radio base station eNodeB 26 side from the mobile station UE 27
as an RRC UL Information Transfer signal (sequence Seq 61), the radio base
station eNodeB 26 sends to the mobile management node MME 22 an EMM Attach
Complete signal that indicates that the attach processing has becn completed
20 (sequence Seq 62). The mobile management node MME 22 that has received the
EMM Attach Complete signal sends an EMM Information signal to the mobile
station UE 27 through the radio base station eNodeB 26 (sequence Seq 63).
[0094]
As described above, the mobile management node MME 22 that has
25 received the usual attach request from the mobile terminal, i.e., the mobiIe station
UE 27 becomes a state of performing cominunication using the communication
session held previous time as it is without carrying out the usual attach processing
of the core network side.
100951
3 0 (Third operation example)
Next, using sequence charts of Figs. 9 and 10, will be explained an example
of the operation of the mobile communication network system of the E-UTRAN
scheme shown in Fig. 2, the exainple being different from the second embodiment
Also in the third operation example, it is possible to reduce the attachldetach
processing of the core network (core node) side similarly to the case of the scco~ld
embodiment as the mobile communication network system of the E-UTRAN
scheme. Here, in the case of the sequence chart of Fig. 7 of the second operation
example, the case has been shown where in receiving the EMM Detach Request
5 signal (detach request signal) that requests detach from the mobile terminal, i.e.,
the mobile station UE 27 via the radio base station eNodeB 26 in sequence Seq 72,
the mobile management node MME 22 determines whether or not the mobile
terminal, i.e., the mobile station UE 27, is the mobile terminal as the target of the
attachldetach processing reduction by referring to the terminal information or the
10 subscriber information etc. in which the attributes of the mobile terminal have
been registered.
[0096]
However, in the sequence charts of Figs. 9A and 9B of the third operation
example, in the mobile communication network system of the E-UTRAN scheme,
15 information that indicates whether or not the mobile station UE 27 is the mobile
terminal as a target of attachldetach processing reduction is added as a parameter
to an EMM Detach Request signal (detach request signal) sent to the radio base
station eNodeB 26 from the mobile terminal, i.e., the mobile station UE 27.
Furthermore, a case is shown where in receiving the EMM Detach Request signal
20 (detach request signal) that requests detach from the mobile terminal, i s . , the
mobile station UE 27 via the radio base station eNodeB 26 in sequence Seq 72, the
mobile management node MME 22 determines whether or not the mobile terminal,
i.e., the 111obile station UE 27, is the mobile terminal as the target of the
attachldetach processing reduction by referring to the parameter added to the
25 received EMM Detach Request signal.
COO971
Figs. 9A and 9B are sequence charts showing an example of the operation
in the case of omitting the usual detach processing of the core network side when
the detach request signal has been sent from the mobile station UE 27 in the mobile
30 communication network system of Fig. 2, the example being different from Fig. 7.
Figs. 1 OA and 10B are sequence charts showing one example of operation in a case
of omitting the usual attach processing of the core network side when an attach
request signal has been sent from mobile station UE 27 after omission of the
detach processing of Figs. 91% and 9B in the mobile communication network system
3 1
of Fig. 2. It is to be noted that as in the casc of the first attach request etc.,
operation in the case of carrying out the usual attach processing shall be
completely similar to the operation of the sequencc charts of Figs. 6A and 6B of
the second operation example.
5 [0098]
Next, using the sequence charts of Figs. 9A and 9B, will be explained one
example of the operation in a case of omitting the usual detach processing of the
core network side even though a detach request is generated from the mobile
station UE 27 in a state where the attach processing has been executed in Figs. 6A
10 and 6B.
100991
The mobile station UE 27 sets a radio control link through which a control
signal is transmitted and received to and from the radio base station eNodeB 26,
and sends to the radio base station eNodeB 26 an EMM Detach Request signal
15 (detach request signal) that requests detach for the mobilc management node MME
22 (sequence Seq 71). Here, unlike the case of the EMM Detach Request signal
in sequence Seq71 of Fig. 7, a sleep notification that indicates that a power source
of the mobile station UE 27 transitions to a sleep state is added to the EMM Detach
Request signal as a parameter that indicates that the mobile station UE 27 is the
20 mobile terminal as the target of detach processing reduction.
[O loo]
When an EMM Detach Request signal of the S 1-AP-Uplink NAS Transport
form is sent fro111 the radio base station eNodeB 26 that has received the EMM
Detach Request signal (sequence Seq 72), the mobile management node MME 22
2 5 confirms whether or not the slcep notification is added to the received EMM
Detach Request signal as ihe parameter that indicates that the mobile btation UE 27
is the lnobile terminal as the target of'the detach processing reduction.
[OlOl]
If the sleep notification is not added to the received EMM Detach Request
30 signal, it is a case of carrying out the usual detach processing of the core network
side, and the mobile management node MME 22 carries out a detach procedure of
the core network side including sequences Seq 73 to Seq 80 of Fig. 9A (completely
the same sequences as sequences Seq 73 to Seq 80 of Fig. 7).
[O 1021
If the sleep notification is added to the received EMM Iletach Request
signal, it is a case where the usual detach processillg of the core network side call
be omitted, and the mobile management node MME 22 omits the detach procedure
of the core network side including sequences Seq 73 to Seq 80 of Fig. 9A
5 (completely the same sequences as sequences Seq 73 to Seq 80 of Fig. 7). and
~rocessingp roceeds to sequence Seq 81, remaining in the state of holding a
communication session (Session). The mobile management node MME 22 then
sends to the radio base station eNodeB 26 of which the mobile station UE 27 as the
request source is in the service area the EMM Detach Accept signal to which the
10 sleep notification has been additionally added as the parameter that indicates that
the detach processing of the core network side has not been carried out (sequence
Seq 81). After that, the radio base station eNodeB 26 sends an EMM Detach
Accept signal to the mobile station UE 27 as the request source (sequence Seq 83).
[0103]
15 Accordingly, also after that, similarly to the case of the second operation
example, the core network side including the mobile management node MME 22
does not transition to a state of Signalling Connection Release of sequence Seq 82,
and only a radio block for accessing the core network transitions to the state of
Signalling Connection Release, with session information of the mobile terminal,
20 i.e., the mobile station UE 27 being continued to be held. Radio resources
between the mobile station UE 27 and the radio base station eNodeB 26 are hereby
released, and connection of a signal for packet service of the mobile station UE 27
with the core network side is opened (sequence Seq 84). That is, as for the radio
resources between the mobile station UE 27 and the radio base station eNodeB 26,
25 e s t a b l i s l ~ ~ ~ ~ e ~ ~ t l rise lceeratsaein ly carried out in each timc of attachldetach
processing regardless of omission of the detach processing of the core network
side.
[0 1041
It is to be noted that when only the radio block for accessing the core
30 network transitions to the state of Signalling Connection Release, remaining in the
state of holding the communication session (Session) in the core network side, in
order to prevent release failure of the communication session of the network side,
similarly to the case of the second operation example, in sequence Seq 81, the
mobile management node MME 22 sets to a session holding timer a time a little
longer by a predetermined time than a generation interval of a reattacl~/redctach
request from the mobile terminal, i.e., the mobile station UE 27 as a time to wait
for forced release of the session.
[0105]
5 After that, when the session holding timer expires, for example, when the
reattachlredetach request from the mobile terminal, i.e., the mobile station UE 27,
is not generated once a day, the mobile management node MME 22 carries out the
usual detach processing of sequences Seq 73 to Seq 80, deletes information on the
communication session of the mobile station UE 27 that has been held in the core
10 network side including the mobile management node MME 22, and releases the
session.
[0 1061
Furthermore, when sending the EMM Detach Accept signal to which the
parameter of the sleep notification has been added to the radio base station eNodeB
15 26 of which the mobile station UE 27 as the request source is in the service area
without carrying out the detach processing, similarly to the second operation
example, the mobile management node MME 22 stops a periodic TAU (Tracking
Area Update) waiting timer that is the timer for periodically updating a location
registration area, and also cancels a subsequent paging request until a reattach
20 request from the mobile station UE 27 is generated, or the session holding timer
expires.
[0 1071
Next, using sequence charts of Figs. 10A and 10B, will be explained one
example of operation in a case of omitting the usual attach processing of the core
2 5 network side when an attach request is generated from thc mobile station UE 27 in
a state where the detach processing is omitted in Figs. 9A and 9B. When the
attach request is generated from the mobile station UE 27, usually, attach
processing as illustrated in Figs. 6A and 6B is carried out, but when generated is
the attach request from the mobile station UE 27 in the state where the detach
30 processing is omitted, as shown in Fig. 10A, similarly to the case of the second
operation example, the usual attach processing of the core network side is omitted,
and processing of sequences Seq 45 to Seq 55 is omitted.
[O 1083
Here, the mobile terminal, i.e., the mobile station UE 27 adds a wake up
notification that indicates that the power source of the nlobile station UE 27
transitions to a wake up state to an EMM Attach Request signal as a parameter that
indicates that the mobile statio~lU E 27 is the mobile ternlinal as a target of attach
processing reduction. In such a case, the mobile terminal, i.e., the mobile station
5 UE 27, holds an old Security context allocated at the time of the last attach
processing, and transmits the EMM Attach Request signal (attach request signal)
using the held old Security context to the radio base station eNodeB 26 (sequence
Seq 41). Accordingly, the radio base station eNodeB 26 adds the wake up
notification as the parameter that indicates that the mobile station UE 27 is the
10 mobile terminal as the target of the attach processing reduction, and sends to the
mobile management node MME 22 the EMM Attach Request signal using the old
Security context (sequence Seq 42).
[OI 091
The mobile management node MME 22 adds as the parameter the wake up
15 notification sent from the mobile station UE 27 through the radio base station
eNodeB 26. .Furthermore, when receiving the EMM Attach Request signal using
the old Security context, the mobile management node MME 22 dctermines
whether or not the mobile station UE 27 is the mobile terminal for which the
detach processing to the communication session in having performed the attach
2 0 processing previous time was omitted as a result of analyzing the EMM Attach
Request signal. If determining that the EMM Attach Request signal is a reattach
request from the mobile station UE 27 for which the detach processing was
omitted, similarly to the second operation cxample, the mobile management node
MME 22 omits to carry out security processing, such as authentication as the core
25 network rcgarding the mobile station UE 27 as thc request source, secret
processing, and integrity, and continues to use the old Security context as it is
(sequences Seq 43 and 44).
[OIIO]
Furthermore, the mobile management node MME 22 omits attach
30 processing of the core network side of sequences Seq 45 to Seq 55, adds a wake up
notification as a parameter that indicates that the attach processing of the core
network side has not been carried out, and sends to the radio base station eNodeB
26 of which the mobile station UE 27 as the request source is in the service area an
EMM Attach Accept signal of the S1-AP-Initial Context Setup Request form that
indicates that the rcattach processing requested from the nlobile station UE 27 has
been completed (sequence Seq 56). After that, after carrying out setting
processing of a radio line for accessing the core network with respect to the mobile
station UE 27 as the request source by a procedure similar to the usual attach
5 processing, the radio base station eNodeB 26 sends to the mobile management
node MME 22 from the radio base station eNodeB 26 an S1-AP-Initial Context
Setup Response signal that indicates that the EMM Attach Accept signal of the
S1-AP-Initial Context Setup Request form has been received (sequence Seq 60).
[0111]
10 Furthermore, similarly to the case of the usual attach processing, when
receiving information (Uplink Information) on an uplink direction of the radio line
that goes to the radio base station eNodeB 26 side from the mobile station UE 27
as an RRC UL Information Transfer signal (sequence Seq 61), the radio base
station eNodeB 26 sends to the mobile management node MME 22 an EMM Attach
15 Complete signal that indicates that the attach processing has been completed
(sequence Seq 62). The mobile management node MME 22 that has received the
EMM Attach Complete signal sends an EMM Information signal to the mobile
station UE 27 through the radio base station eNodeB 26 (sequence Seq 63).
[0112]
2 0 As described above, as information to determine whether or not the mobile
terminal, i.e., the mobile station UE 27, is the mobile terminal as the target of the
attachldetach processing reduction, also in the third operation example using the
parameters (the sleep notification and the wake up notification) added to the
detachlattach request signal, similarly to the case of the second operation example
25 where the information that indicates the attributes of the ternliaal, such as thc
terminal information and the subscriber information of the mobile terminal, i.e.,
the mobile station UE 27, at the time of the detachlattach request, the mobile
management node MME 22 that has received the usual attach request from the
mobile terminal, i.e., the mobile station UE 27, becomes the state of performing
30 communication using the communication session held last time as it is without
carrying out the usual attach processing of the core network side.
[0113]
(Explanation of effect of embodiment)
As explained in detail above, the following effect can be obtained in the
cmbodirncnt. Namely, since the enlbodinlent ~nakcsit possible to omit the
attachldetach processing of the core network side depending 011 the terminal
infornlation and the subscriber information that indicate the attributes of the
mobile tern~inal( the mobile station MS 16 or the mobile station UE 27) that
5 requests attachldetach, or a parameter added in addition to the attachldetach
request signal, it becomes possible to decrease a load of the core network side even
in a case where a large amount of mobile terminals (the mobile station MS 16 or
the mobile station UE 27) are contained.
roll41
10 Hereinbefore, configurations of the preferred embodiments of the present
invention have been explained. However, note that such embodiments are mere
exemplifications of the present invention, and do not limit the present invention at
all. Those skilled in the art can easily understand that various modifications and
changes can be made according to a particular application without departing from
15 the gist of the present invention.
[0115]
Although the present invention is described as a hardware configuration in
the above exemplary embodiments, the present invention is not limited thereto.
The present invention may be implemented by causing a CPU (Central Processing
20 Unit) to execute a computer program to perform a given process.
[0116]
Further, thc above-described program can be stored and provided to the
computer using any type of non-transitory computer readable medium. The
non-transitory computer readable medium includcs any type of tangible storage
2 5 medium. Exanlples of the non-transitory computer readable medium include
magnetic storage media (such as floppy disks, magnctic tapes, hard disk drives,
etc.), optical magnetic storage media (e.g. magneto-optical disks), CD-ROM (Read
Only Memory), CD-R , CD-RIW, and semiconductor memories (such as mask
ROM, PROM (Programmable ROM), EPROM (Erasable PROM), flash ROM, RAM
30 (Random Access Memory), etc.). The program may be provided to a computer
using any type of transitory computer readable medium. Exan~pleso f the transitory
computer readable medium include electric signals, optical signals, and
electromagnetic waves. The transitory computer readable medium can provide the
program to a computer via a wired co~nmunicationl ine such as an electric wire or
optical fiber or a wireless conlnlunication line.
[0117]
Hereinbefore, although the invention in the present application has been
explained with reference to the embodiments, the invention in the present
5 application is not limited by the above. Various changes that those skilled in the
art can understand within the scope of the invention can be made to the
configuration and the details of the invention in the present application.
[0118]
This application is based upon and claims the benefit of priority from
10 Japanese patent application No. 201 1-214409, filed on September 29, 201 1, the
disclosure of which is incorporated herein in its entirety by reference.
Reference Signs List
101 191
15 11 Subscriber Information Management Device HLR (Home Location
Register)
12 Subscriber Location Register VLR (Visitor Location Register)
13 Packet Switch SGSN (Serving GPRS (General Packet Radio Service)
Support Node)
20 14 Gateway Packet Switch GGSN (Gateway GPRS Support Node)
15 Radio Line Control Station RNC (Radio Network Controller)
16 Mobile Station MS (Mobile Station)
2 1 Subscriber Inforn~ationM anagement Device HSS (Ilome Subscriber
Server)
25 22 Mobile Managenlent Node MME (Mobility Management Entity)
23 Subscriber PolicyICharging Rule Management Device PCRF (I'olicy and
Charging Rules Function)
24 PDN Gateway Device P-GW (PDN Gateway)
2 5 Relay Gateway Device S-GW (Serving Gateway)
30 26 Radio Base Station eNodeB (Enhanced Node B)
2 7 Mobile Station UE (User Equipment)
WE CLAIM:
1. A lnobile con~municationn etwork system comprising a core network
accessed from a mobile terminal through a radio line, wherein
5 in a detach request signal that requests detach being received from the
mobile terminal, the radio line is released in a state of holding a communication
session of the core network side set in the mobile terminal having attached, and
in an attach request signal that requests attach being received from the
mobile terminal, the held communication session of the core network side is used,
10 and setting of the radio line is performed.
2. The mobile communication network system according to Claim 1, wherein
a mobile management node arranged on the core network side in order to perform
management control of mobile communication determines whether or not detach
15 processing and attach processing of the core network side are omitted depending
on terminal information and subscriber information that indicate attributes of the
mobile terminal, or depending on a parameter addcd to the attach request signal
and the detach request signal.
20 3. The mobile communication network system according to Claim 1 or 2,
wherein when receiving the detach request signal from the mobile terminal, and
omitting the detach processing of the core network side, a mobile management
node arranged on the core network side in order to perform management control of
mobile communication sets to a session holding timer a time a little longer by a
2 5 predetermined time than a generation interval of a reattachlredetach requcst from
the mobile terminal as a time to wait for forced release of the held communication
session, and when the session holding timer expires without receiving the attach
request signal from the mobile terminal, the mobile management node deletes
infornlation on the held communication session by making usual detach processing
30 of the core network side carried out, and forcibly releases the commuilication
session.
4. The mobile comlnunication network system according to Claim 3, wherein
when omitting the detach processing of the core network side in receiving the
39
detach request signal from the mobile ternlinal, and setting to the session holding
timer the time to wait for forced release of the held corn~nunications ession, the
mobile managetnent node stops a tinler for periodically updating a routing area,
and cancels a subsequent paging request until a reattach request from the mobile
5 terminal is generated, or the session holding timer expires.
5. The mobile co~nmunicationn etwork system according to any of Claims 1 to
4, wherein a mobile management node arranged on the core network side in order
to perform management control of mobile communication is a packet switch SGSN
10 (Serving GPRS (General Packet Radio Service) Support Node) established in a
3GPP standard, or a mobile management node MME (Mobility Management
Entity).
6. A communication control method used in a mobile communication network
15 system comprising a core network accessed from a mobile terminal through a radio
line, wherein
in a detach request signal that requests detach being received from the
mobile terminal, the radio line is released in a state of holding a communication
session of the core network side set in the mobile terminal having attached, and
2 0 in an attach request signal that requests attach being received from the
mobile terminal, the held communication session of the core network side is used,
and setting of the radio line is performed.
7. The communication control method according to Claim 6, wherein a nlobile
2 5 nlanagelnent node arranged on the core network side in order to perform
management control of mobile communication determines whether or not detach
processing and attach processing of the core network side are omitted depending
on terminal information and subscriber information that indicate attributes of the
mobile terminal, or depending on a parameter added to the attach request signal
3 0 and the detach request signal.
8. The communication control method according to Claim 6 or 7, wherein
when receiving the detach request signal from the mobile terminal, and omitting
the detach processing of the core network side, a mobile management node
40
arranged on the core nctwork side in order to perform managcrncnt control of
mobile communication sets to a session holding timer a time a little longer by a
predeternlincd time than a generation interval of a reatiachlredeiach request from
the mobile terminal as a time to wait for forced release of the held communication
5 session, and after that, when the session holding timer expires without receiving
the attach request signal from the mobile terminal, the mobile management node
deletes information on the held communication session by making usual detach
processing of the core network side carried out, and forcibly releases the
communication session.
10
9. The communication control method according to Claim 8, wherein when
omitting the detach processing of the core network side in receiving the detach
request signal from the mobile terminal, and setting to the session holding timer
the time to wait for forced release of the held comn~unications ession, the mobile
15 management node stops a timer for periodically updating a routing area, and
cancels a subsequent paging request until a reattach request from the mobile
terminal is generated, or the session holding timer expires.
10. A non-transitory computer readable medium storing a mobile terminal
2 0 attachldetach processing program for making a computer provided at a mobile
management node arranged on the core network side in order to perform
management control of mobile communication execute the communication control
method according to any of Claims 6 to 9.