2
DESCRIPTION
Title of Invention
COMMUNICATIONS SYSTEM
Technical Field
[0001]
The present invention relates to a communications system and to parts and
methods thereof. The invention has particular but not exclusive relevance to
wireless communications systems and devices thereof operating according to the
3GPP standards or equivalents or derivatives thereof.
Background Art
[0002]
Wireless communications systems enable users of User Equipment (UE) to
communicate with other such users via one of a number of base stations and a core
network. Typically, the UEs are mobile terminals, such as cellular telephones
and the like. In an active or connected state a UE is registered with the network
and has a Radio Resource Control (RRC) connection with a base station so that the
network knows to which base station (or cell thereof) the UE belongs and can
transmit data to and receive data from the UE. The base station (i.e. the serving
cell) provides mobility information and security parameters for the user
equipment. The UE also establishes a default Evolved Packet System (EPS) Bearer
at an endpoint beyond the base station, typically a gateway, in the Enhanced
Packet Core (EPC) network, or core network for short. An EPS Bearer defines a
transmission path through the network and assigns an IP address to the UE, at
which it can be reached by other communication devices, such as another UE. An
EPS Bearer also has a set of data transmission characteristics, such as quality of
service, data rate and flow control parameters, which are defined by the
subscription associated with the UE and are established by the Mobility
Management Entity (MME) upon registration of the UE with the network.
[0003]
The EPS Bearer is thus managed by the MME, which signals to the UE
when it needs to activate, modify, or deactivate a particular EPS Bearer. Thus
3
there are always two connections between the UE and the communication network:
one for the user data transmitted using the established EPS bearer (also known as
the user plane) and another one for managing the EPS Bearer itself (also known as
the control plane).
[0004]
As part of the Long Term Evolution (LTE) of UTRAN (UMTS Terrestrial
Radio Access Network) referred to as E-UTRAN, there are plans to introduce a
feature of proximity based (e.g. direct device-to-device (D2D) or locally routed)
communication when the UE can communicate user data to another UE that is
within the transmission range of (or served by the same base station as that of) the
first UE without the need to use LTE core network resources. Such services can
be achieved by establishing a special, relaying EPS bearer to be used by the mobile
communication devices in direct or locally routed communication instead of their
default or other conventional EPS bearers (which might still be used for other
types of communications). This direct or locally routed communication would
result in better utilization of the available resources, especially on the radio
interface, where these are limited. A so-called Proximity-based Services (ProSe)
functionality has been specified in the 3GPP TR 22.803 (vl2.1.0) standards
document, the contents of which are incorporated herein by reference.
[0005]
More recently the provision of a relay functionality, in the UE, using the
ProSe functionality has been proposed to allow one UE to relay the signalling for
another UE to and from the network.
[0006]
Due to the added complexity represented by the above functionalities and
the like, it is important to ensure that each network element operates in
conformance with the applicable set of standards (in this case the 3GPP standards).
Since proximity based services significantly increase the complexity of the mobile
communication devices (and other user equipment), there is a strong desire to test
implementation of these (and similar) functionalities by the mobile communication
devices before they are released to the market (or whilst they are in use in a
communications network). However, the testing of such UE specific functions
needs to be supported by the mobile communication device as well.
[0007]
4
As known to a person skilled in the art, a so-called System Simulator (SS)
entity may be used for testing compliance (and/or performance) of a network
element, such as a base station or user equipment. The SS entity does this by
simulating the operation of another network element (i.e. that would otherwise
communicate with the device to be tested in a 'live' network). In addition to this,
the SS entity controls the overall test process, including the operating parameters
of a mobile communication device (in case the mobile communication device is
being tested), such as activating/deactivating features, and setting an operating
mode (e.g. normal mode, test mode, etc.).
[0008]
The SS entity activates the test mode for the mobile communication device
in which the SS entity is able to set up (remotely) one or more communication
paths terminating in a so-called loopback function of the mobile communication
device (from where the data units originating from the SS entity are forwarded or
'looped-back' to the SS entity). This effectively means that the SS entity is able
to monitor communications by the mobile communication device taking place via
the looped back communication path(s). Then, by monitoring and analyzing the
communication taking place using the communication path(s) terminating in the
loopback function, it is possible to determine whether or not the behaviour of the
device being tested is in line with what is prescribed in the relevant set of
standards (in which case conformance to that set of standards can be certified
and/or the product can be released to the market). However, if the behaviour of
the device being tested is not in line with the relevant set of standards, it is
possible to determine suitable actions (e.g. re-design / re-configuration /
re-calibration of that device) so that conformance to the relevant set of standards
can be achieved before using the device in a 'live' communication system.
[0009]
The relevant mechanisms developed by 3GPP for special conformance
testing functions are defined in TS 36.509 (for user equipment in E-UTRA
frequency division duplex (FDD) mode and time division duplex (TDD) mode) and
in TS 34.109 (for user equipment in UMTS system, for FDD and TDD modes).
The contents of both documents are incorporated herein by reference.
[0010]
In summary, the above specifications describe the functions and their
5
activation/deactivation methods that each LTE / UMTS mobile communication
device is required to implement for conformance testing purposes.
[0011]
The UE test loop function provides access to isolated functions of the
mobile communication device via the radio interface without requiring the
presence and/or usage of a physical connection (e.g. a hardware interface) between
the mobile communication device and the SS entity for conformance testing.
However, it will be appreciated that the mobile communication device may also be
connected to the SS entity using wired communication means (e.g. a Radio
Frequency (RF) cable), for example, to avoid/reduce interference during test and
hence increase test reliability.
[0012]
For E-UTRA, the following loop modes have been defined:
UE test loop mode A
UE test loop mode B
UE test loop mode C
[0013]
UE test loop mode A provides loopback of data packets (e.g. Packet Data
Convergence Protocol (PDCP) Service Data Units (SDUs)) for bi-directional data
radio bearers while the UE is operating in E-UTRA mode. The downlink PDCP
SDUs received by the UE on each bi-directional data radio bearer are returned on
the same radio bearer regardless of the PDCP SDU contents and the Traffic Flow
Template (TFT) of the associated EPS bearer context.
[0014]
UE test loop mode B provides loopback of PDCP SDUs (E-UTRA and
UTRA), Sub Network Dependent Convergence Protocol (SNDCP) Protocol Data
Units (PDUs) (in GSM/GPRS) and Radio Link Protocol (RLP) PDUs (CDMA2000)
for bi-directional EPS bearers while the UE is operated in E-UTRA, UTRA,
GSM/GPRS or CDMA2000 modes. UE test loop mode B can not be used when
more than one PDN connection is established or more than one primary Packet
Data Protocol (PDP) context is active. When operating in E-UTRA, UTRA or
GSM/GPRS then the downlink PDCP SDUs or SNDCP PDUs received by the UE on
all bi-directional data radio bearers are returned by the UE on the data radio bearer
associated with an EPS bearer context with a TFT matching the Transmission
6
Control Protocol (TCP) / User Datagram Protocol (UDP) / Internet Protocol (IP)
information within the PDCP SDU or SNDCP SDU. When operating in
CDMA2000 modes, the downlink RLP PDUs received by the UE on all
bi-directional data radio bearers are returned by the UE on the data radio bearer
5 with the smallest identity, regardless of the RLP PDU content and the TFT of the
associated EPS bearer context.
[0015]
UE test loop mode C provides counting of successfully received
Multimedia Broadcast and Multicast (MBMS) Packets on a given MBMS traffic
10 channel (MTCH) while the UE is operating in Evolved MBMS (E-MBMS)/E-UTRA
mode.
Citation List
Non Patent Literature
15 [0016]
NPL 1: 3GPP TR 22.803 (vl2.1.0) standards document
NPL 2: 3GPP TS 36.509 technical specification
NPL 3: 3GPP TS 34.109 technical specification
20 Summary of Invention
Technical Problem
[0017]
However, each of these loop-modes is limited to certain test scenarios, and
is relatively inflexible. For example, these loop-modes do not allow provision of
25 a certain functionality (e.g. a relay function of a UE relay (UE-R)) to continue,
unaffected, while the loopback function is being employed. Further, when a
relaying functionality is implemented, it is not currently possible to test the
conformance of this relay functionality to the above standards because of the
limitations of the current test modes.
30 [0018]
Loop mode A, for example, only allows to loopback a Radio bearer, not an
EPS bearer (i.e. at PDCP level). For this loopback mode, the SS will indicate to
the UE which Radio Bearer will need to be associated with a loopback function.
Loop mode B only works when 1 PDN connection is activated. This is a known
7
restriction from the specification. This loopback mode doesn't allow
differentiating the different EPS bearers and all activated bearers will terminate in
a single loop back entity which will send the PDCP SDU to the UL TFT SAP
(Service Access Point) for transmission in an uplink. Loop mode C is restricted
5 to MBMS.
Solution to Problem
[0019]
In one aspect, the invention provides a communication device for
10 communicating with a communication network test device operable to monitor
operation of said communication device, the communication device comprising:
means for operating a plurality of communication bearers associated with said
communication device; means for determining a subset comprising at least one
communication bearer, selected from said plurality of communication bearers, to
15 be used when performing a test and not comprising at least one other
communication bearer of said plurality of communication bearers; and means for
communicating with the communication network test device in pursuance of a test
in which each communication bearer in said subset is used and each
communication bearer not in said subset is not used.
20 [0020]
The communication device may further comprise means for receiving a
message, from said communication network test device, the message comprising
data identifying each communication bearer in said subset, wherein said
determining means is operable to determine said subset based on said data
25 identifying each communication bearer in said subset.
[0021]
In another aspect, the invention provides a communication network test
device for monitoring operation of a communication device, the test device
comprising: means for communicating with said communication device; means for
30 identifying each of a plurality of communication bearers associated with said
communication device; means for determining a subset comprising at least one
communication bearer, selected from said plurality of communication bearers, to
be used when performing a test and not comprising at least one other
communication bearer of said plurality of communication bearers; and means for
8
initiating a test in which each communication bearer in said subset is used and
each communication bearer not in said subset is not used.
[0022]
The communication network test device may send a message, to said
5 communication device, the message comprising data identifying each
communication bearer in said subset. Alternatively, the communication network
test device may send a message, to said communication device, the message
comprising data identifying each communication bearer not in said subset. In this
case, the communication device may determine said subset based on said data
10 identifying each communication bearer not in said subset.
[0023]
The message may comprise a bit pattern with at least one respective bit
associated with each communication bearer of said plurality of communication
bearers associated with said communication device. In this case, each said bit
15 may be set to a predetermine value if said communication bearer is in said subset.
[0024]
Alternatively, the message may comprise a bit pattern with at least one
respective bit associated with a default communication bearer of said plurality of
communication bearers associated with said communication device. In this case,
20 each said bit may be set to a predetermine value if said default communication
bearer and any associated communication bearer is in said subset.
[0025]
The message may comprise a bearer identifier, e.g. an Evolved Packet
System (EPS) Bearer ID (or EBI) for each communication bearer of said subset.
25 The message may comprise a Non-Access Stratum (NAS) message. In this case,
the NAS message may be embedded in at least one Radio Resource Control (RRC)
message. The at least one message may comprise a downlink information transfer
message.
[0026]
30 The test initiated by said initiating means may be a loop-back test. The
communication network test device may send test packets to said communication
device using said at least one communication bearer of said subset. The
communication network test device may receive, as part of said test, test packets
from said communication device.
9
[0027]
The plurality of communication bearers may comprise at least one EPS
communication bearer.
[0028]
5 The determining means may select communication bearers for said subset
to be communication bearers that are not associated with at least one specific
functionality of said communication device (e.g. a relay functionality or non-relay
functionality). Alternatively, the determining means may select communication
bearers for said subset to be communication bearers that are associated with at
10 least one specific functionality of said communication device (e.g. a relay
functionality or non-relay functionality). The determining may determine, when
said test has been initiated, at least one communication bearer of said subset for
which said test is to be terminated.
[0029]
15 The communication network test device may initiate termination of said at
least one communication bearer of said subset for which said test is to be
terminated. The communication network test device may send a message to
terminate said test to said communication device, the message to terminate said
test comprising data identifying each communication bearer for which said test is
20 to be terminated.
[0030]
The message to terminate said test may comprise a bit pattern with at least
one respective bit associated with each communication bearer of said plurality of
communication bearers associated with said communication device. In this case,
25 each said bit may be set to a predetermined value if said test is to be terminated for
said communication bearer. The message may comprise a bearer identifier (e.g.
an EPS Bearer ID or EBI) for each communication bearer of said subset for which
said test is to be terminated. Alternatively, the message may comprise a NAS
message. In this case, the NAS message may be embedded in at least one RRC
30 message. The at least one message may comprise a downlink information transfer
message.
[0031]
In yet another aspect, the invention provides a communication device for
communicating with a communication network test device operable to monitor
10
operation of said communication device, the communication device comprising a
processor operable to: operate a plurality of communication bearers associated
with said communication device; determine a subset comprising at least one
communication bearer, selected from said plurality of communication bearers, to
5 be used when performing a test and not comprising at least one other
communication bearer of said plurality of communication bearers; and
communicate with the communication network test device in pursuance of a test in
which each communication bearer in said subset is used and each communication
bearer not in said subset is not used.
10 [0032]
In a further aspect, the invention provides a communication network test
device for monitoring operation of a communication device, the test device
comprising a processor operable to: communicate with said communication device;
identify each of a plurality of communication bearers associated with said
15 communication device; determine a subset comprising at least one communication
bearer, selected from said plurality of communication bearers, to be used when
performing a test and not comprising at least one other communication bearer of
said plurality of communication bearers; and initiate a test in which each
communication bearer in said subset is used and each communication bearer not in
20 said subset is not used.
[0033]
The invention also provides a communication system comprising the above
communication device and the above communication network test device. The
invention also provides, for all test system entities and user devices disclosed,
25 corresponding methods and computer programs or non-transitory computer-readable
medium for execution on corresponding user equipment or network communications
devices.
Advantageous Effects of Invention
30 [0034]
According to the present invention, it can be achieved to provide methods
and an apparatus which overcome or at least partially alleviate the above issues.
Brief Description of Drawings
11
[0035]
Embodiments of the invention will now be described, by way of example,
with reference to the accompanying drawings, in which:
[Fig. 1]
5 Fig. 1 illustrates schematically a cellular telecommunications system to
which embodiments of the invention may be applied;
[Fig. 2]
Fig. 2 illustrates an EPS bearer architecture used in the communication
system illustrated in Fig. 1;
10 [Fig. 3]
Fig. 3 illustrates schematically a relayed bearer structure compared to the
core network routed bearer structure used in the communications system shown in
Fig. 1;
[Fig. 4]
15 Fig. 4 illustrates schematically exemplary test environment scenarios for
verifying compatibility of a mobile communication device with the communication
system illustrated in Fig. 1;
[Fig. 5]
Fig. 5 is a functional block diagram illustrating some of the functionality of
20 a test system entity forming part of the system shown in Fig. 3;
[Fig. 6]
Fig. 6 is a functional block diagram illustrating some of the functionality of
a mobile communication device forming part of the system shown in Fig. 1;
[Fig. 7]
25 Fig. 7 illustrates schematically a test environment according to an
embodiment of the invention for verifying compatibility of a mobile
communication device with the communication system illustrated in Fig. 1; and
[Fig. 8]
Fig. 8 is a timing diagram illustrating the way in which the test system
30 entity controls the activation of a loopback connection for the mobile
communication device according to an embodiment of the invention.
Description of Embodiments
[0036]
12
(Overview)
Fig. 1 schematically illustrates a communication system (communications
network) 1 in which users of mobile communication devices (in this example
mobile telephones 'MTs') 3-1 to 3-3 can communicate with each other and other
5 users via E-UTRAN base stations 5-1 and 5-2 and core network 7. As those
skilled in the art will appreciate, three mobile communication devices 3 and two
base stations are illustrated in Fig. 1 for illustration purposes and others will be
provided in a deployed system. Conventionally, when the mobile communication
devices 3-1 and 3-2 are in communication with each other, user plane data is
10 routed from the user equipment (mobile communication device) 3-1 to the base
station 5-1, through the core network 7, back to the base station 5-1 and to the
mobile communication device 3-2 (and similarly for user plane data sent in the
opposite direction). Similarly, when the mobile communication devices 3-1 and
3-3 are in communication with each other, user plane data is conventionally routed
15 from the user equipment (mobile communication device) 3-1 to the base station
5-1, through the core network 7, to the base station 5-2 and to the mobile
communication device 3-3 (and similarly for user plane data sent in the opposite
direction).
[0037]
20 The communication paths described above ensure that data is transmitted
between the mobile communication devices 3 in compliance with the relevant
subscription parameters and also respecting the service criteria required by the
mobile communication devices 3 and the security criteria imposed by the network.
However, such a conventional arrangement is wasteful of resources in the base
25 stations 5 and in the core network 7, as the two mobile communication devices 3
are within radio communications range of each other and thus a direct user plane
communication link can be used instead, for example, as indicated in Fig. 1 by a
line with an arrow at each end between the mobile communication devices 3-1 and
3-2. Moreover, the mobile communication device 3-1 is provided with a relaying
30 functionality to allow user data to be relayed from the mobile communication
device 3-3 to the network, as indicated by respective lines each with an arrow at
one end between the mobile communication devices 3-1 and 3-3 and the serving
base station 5-2.
[0038]
13
Therefore, in this embodiment, the communication system
(communications network) 1 also supports device-to-device, locally routed, and
relayed user plane communication between compatible mobile communication
devices 3.
5 [0039]
Fig. 1 also shows a so-called system simulator (SS) entity 11, which
normally does not form part of a deployed communication system. Instead, the
SS entity 11 is used for testing purposes, for example, to test compatibility of
various network elements with the other network elements and also to verify
10 compliance of these network elements with the applicable standards.
[0040]
In this embodiment, the SS entity 11 is used for verifying compliance of a
mobile communication device 3 with the applicable standards using proximity
based services. The SS entity 11 does this by activating a loopback functionality
15 for the mobile communication device 3, which is used to loop back (i.e. re-route
back to the SS entity 11) selected communication bearers (e.g. communication
bearers not required for providing a relay service) whilst maintaining the normal
routing of other communication bearers (e.g. which are required for the relay
service) or applying loop back over the bearers separately, which is advantageous.
20 [0041]
This 'selective' loopback functionality of the SS entity 11 is achieved by
providing an identification of the EPS bearer to be associated with the loopback
function, which has the benefit of leaving all other communication bearers
unaffected. This ensures that any EPS bearer that is not part of the test procedure
25 can be maintained with its normal functionality whilst the selected (identified)
EPS bearer is being tested. This has the advantage of allowing testing of various
EPS bearer configurations in a mobile communication device 3 for compliance
with proximity based services, for example, the relaying functionality of mobile
communication device 3-1.
30 [0042]
This approach also allows verification of whether or not functionalities
related to multiple on-going services are correctly implemented by the
communications apparatus being tested (e.g. user equipment and/or a network
element).
14
[0043]
(EPS Bearer Architecture)
Before discussing the details of the embodiments of the present invention,
it will be helpful to set out the architecture of the EPS bearers used to carry the
5 data between the mobile communication devices 3 and the base stations 5 / core
network 7. Fig. 2 gives an example of the EPS architecture as extended to
accommodate the direct (D2D) bearer (e.g. a relaying bearer) between the mobile
communication devices 3. Further details can be found in 3GPP TS 23.401
VI 1.5.0, the contents of which are hereby incorporated by reference. In
10 summary, an EPS bearer is realized by the following elements:
[0044]
In the mobile communication device 3, the UL TFT (Uplink Traffic Flow
Template) maps a traffic flow aggregate to an EPS bearer in the uplink direction;
In the PDN GW (Packet Data Network Gateway), the DL TFT (downlink
15 Traffic Flow Template) maps a traffic flow aggregate to an EPS bearer in the
downlink direction;
A radio bearer (as defined in TS 36.300 VI 1.5.0) is a radio link between
two points, with a specific set of associated characteristics, such as quality of
service, volume of traffic, frequency allocation, modulation scheme,
20 synchronization, multiple-input and multiple-output (MIMO) configuration, etc.
Radio bearers can be seen as channels provided by Layer-2 to higher layers for the
transfer of either user data or control data. When a radio bearer is used for
transmitting control data, it is referred to as a Signalling Radio Bearer (SRB).
The radio bearer transports the packets of an EPS bearer between a mobile
25 communication device and a base station 5. Whenever a mobile communication
device 3 is using a service, the service is always associated with a radio bearer
specifying the Tayer-2 and Physical Layer configuration in order to define the
associated transmission parameters. However, these associated parameters can be
updated anytime during the lifetime of a radio bearer, depending on the current
30 requirements imposed by the two endpoints of communication and the current
availability of system resources. If a radio bearer exists, there is a one-to-one
mapping between an EPS bearer and this radio bearer;
An SI bearer transports the packets of an EPS bearer between a base station
5 and a Serving GW 8;
15
An E-RAB (E-UTRAN Radio Access Bearer) refers to the concatenation of
an SI bearer and the corresponding radio bearer, as defined in TS 36.300 VI 1.5.0.
An S5/S8 bearer transports the packets of an EPS bearer between the
Serving GW 8 and the PDN GW 10;
5 - The mobile communication device 3 stores a mapping between an uplink
packet filter and a radio bearer to create the mapping between a traffic flow
aggregate and a radio bearer in the uplink;
The PDN GW 10 stores a mapping between a downlink packet filter and an
S5/S8 bearer to create the mapping between a traffic flow aggregate and an S5/S8
10 bearer in the downlink;
The base station 5 stores a one-to-one mapping between a radio bearer and
an SI Bearer to create the mapping between a radio bearer and an SI bearer in both
the uplink and the downlink;
The Serving GW 8 stores a one-to-one mapping between an SI Bearer and
15 an S5/S8 bearer to create the mapping between an SI bearer and an S5/S8 bearer in
both the uplink and downlink.
[0045]
The PDN GW 10 routes downlink packets to the different EPS bearers
based on the downlink packet filters in the TFTs assigned to the EPS bearers in the
20 PDN connection. Similarly, the mobile communication devices 3 route uplink
packets to the different EPS bearers based on the uplink packet filters in the TFTs
assigned to the EPS bearers in the PDN connection.
[0046]
(EPS and Radio Bearers)
25 Fig. 3 illustrates schematically a relayed bearer structure used in the
communications system shown in Fig. 1.
[0047]
Generally, in communications systems, a bearer can be defined as a
pipeline connecting two or more points in the communications system, in which
30 pipeline data flows. Thus an EPS bearer may be regarded as a pipeline for data to
be sent across the Evolved Packet System (e.g. core network 7), i.e. between the
mobile communication device 3-1 and the P-GW 10. In order to provide an
end-to-end service for the mobile communication device 3-1, the P-GW 10
complements the EPS bearer with an external bearer (i.e. a bearer which is external
16
to the core network 7) towards an endpoint 12 of communication (assuming that
the other endpoint is not served by the core network 7). If the endpoint 12 is
served by the core network 7, then the external bearer is substituted by the
corresponding (and similarly formed) EPS bearer associated with the endpoint 12.
5 [0048]
The EPS bearer used in LTE communications systems may be considered to
be a plurality of components - an S5/S8 bearer between the P-GW 10 and the S-GW
8 and an E-UTRAN Radio Access Bearer (E-RAB) between S-GW 8 and the mobile
communication device 3-1. The E-RAB may, itself, be further divided into an SI
10 Bearer between the S-GW 8 and the base station 5, and a Radio Bearer between the
base station 5 and the mobile communication device 3-1.
[0049]
As can thus be seen, in order to provide an EPS Bearer over the core
network 7, a number of bearer components and a number of network entities are
15 used. Upon registration of the mobile communication devices 3 with the core
network 7, the mobile communication devices 3 establish at least one, i.e. default,
EPS Bearer and subsequently they may establish further EPS bearers, as needed,
e.g. for each type of communication service used by a user of the mobile
communication devices 3. Each EPS Bearer can have its own associated settings
20 (e.g. an IP address, a set of data transmission characteristics, such as quality of
service, data rate and flow control parameters, etc.) in order to provide support for
the different requirements of different communication services.
[0050]
The embodiments described herein make use of a 'Relay' Bearer
25 comprising a Relay EPS bearer and a Relay radio bearer routed directly between
the two mobile communication devices 3-1 and 3-3 and, in the case of the Relay
EPS bearer, on to the P-GW 10.
[0051]
As shown, an end to end service for the relayed mobile communication
30 device can thus be implemented using the Relay EPS bearer between the mobile
communication devices 3-1 and 3-3 and between the mobile communication device
3-3 and the P-GW 10 and other bearers to the end point 12.
[0052]
(Loopback scenarios)
17
Fig. 4 illustrates schematically exemplary test environment scenarios for
verifying compatibility of a mobile communication device 3 with the
communication system 1 illustrated in Fig. 1. In these scenarios, a mobile
communication device 3-1, having relaying functionality, is being tested. The
5 relaying mobile communication device 3-1 maintains a normal EPS bearer with the
core network 7 (via a base station 5-1 or a suitably configured SS entity 11) and at
the same time it also maintains a relay bearer for relaying communication from/to
another mobile communication device 3-3 or a suitably configured SS entity 11.
[0053]
10 As can be seen, in the first scenario, the mobile communication device 3-1
is tested using a conventional base station 5-1 and a conventional mobile
communication device 3-2 in a real network environment. However, this setup
may not provide sufficient feedback on a possible non-compliance and/or
malfunction of the mobile communication device 3-1 being tested because the
15 elements of this test setup have not been designed for the specific purpose of
compliance testing, albeit they may support some (possibly limited) functionalities
related to this kind of testing.
[0054]
In the second scenario, the mobile communication device 3-1 is tested
20 using two of the SS entities 11 for testing its regular EPS bearer(s) and its relay
bearer, respectively. This setup provides sufficient feedback on a possible
non-compliance and/or malfunction of the mobile communication device 3-1 being
tested. However, it requires the two SS entities 1 1, which need to be
synchronized during the compliance test, in order to provide reliable feedback on
25 the mobile communication device's 3 operation.
[0055]
In the third scenario, the mobile communication device 3-1 is tested using a
single SS entity 11-IB for testing both the regular EPS bearer(s) and the relay
bearer as a 'one-box' solution. This setup provides the most reliable feedback on
30 a possible non-compliance and/or malfunction of the mobile communication device
3-1 being tested.
[0056]
(System simulator entity)
Fig. 5 shows a functional block diagram of the system simulator entity 1 1
18
shown in Fig. 1. As shown, the system simulator entity 11 has a transceiver
circuit 51 for transmitting signals to and for receiving signals from other entities
via one or more antenna 53. The system simulator entity 11 has a controller 57 to
control the operation of the system simulator entity 11. The controller 57 is
5 associated with a memory 59. Although not necessarily shown in Fig. 5, the
system simulator entity 11 will of course have all the usual functionality of a
conventional system simulator entity (such as a user interface 55) and this may be
provided by any one or any combination of hardware, software and firmware, as
appropriate. Software may be pre-installed in the memory 59 and/or may be
10 downloaded via, for example, the communication system (communications
network) 1 or from a removable data storage device (RMD). The controller 57 is
configured to control the overall operation of the system simulator entity 11 by, in
this example, program instructions or software instructions stored within the
memory 59. As shown in Fig. 5, these software instructions include, among other
15 things, an operating system 61, a communications control module 63, a radio
resource control (RRC) module 65, a simulation module 66, and a loopback module
67.
[0057]
The communications control module 63 is operable to handle (e.g.
20 generate, send and receive) control signals for controlling the connections between
the system simulator entity 1 1 and mobile communication devices 3 and/or any of
other test equipment entities. The communications control module 63 also
controls the separate flows of uplink data and control data that are to be
transmitted to the mobile communication devices 3.
25 [0058]
The RRC module 65 is operable to handle (e.g. generate, send and receive)
control signals formatted according to the RRC protocol. The RRC module 65 is
also operable to include in an RRC signalling message for the mobile
communication device 3 Non-Access Stratum (NAS) signalling for identifying an
30 EPS bearer of that mobile communication device 3 to be associated with a specific
loopback test.
[0059]
The simulation module 66 controls the behaviour of the system simulator
entity 11 to cause the system simulator entity 1 1 to perform the functions of any
19
specific network entity when required to do so (e.g. base station, core network
entities, and/or mobile devices).
[0060]
The loopback module 67 is operable to interface with the corresponding
5 module of the device being tested (e.g. a loopback module 89 of the mobile
communication device 3) and thereby monitor the operation of the device being
tested, e.g. based on the data units sent/received by that device.
[0061]
(Mobile communication device)
10 Fig. 6 shows a functional block diagram of the relaying mobile
communication device 3-1 shown in Fig. 1. As shown in Fig. 6, the mobile
communication device 3 has a transceiver circuit 71 that is operable to transmit
signals to and to receive signals from a base station 5 and/or another mobile
communication device 3 (and/or an SS entity 11 configured as a base
15 station/mobile communication device) via one or more antenna 73. The mobile
communication device 3 has a controller 77 to control the operation of the mobile
communication device 3. The controller 77 is associated with a memory 79 and is
coupled to the transceiver circuit 71. Although not necessarily shown in Fig. 6,
the mobile communication device 3 will of course have all the usual functionality
20 of a conventional mobile communication device 3 (such as a user interface 75) and
this may be provided by any one or any combination of hardware, software and
firmware, as appropriate. Software may be pre-installed in the memory 79 and/or
may be downloaded via, for example, the telecommunications network or from a
removable data storage device (RMD).
25 [0062]
The controller 77 is configured to control overall operation of the mobile
communication device 3 by, in this example, program instructions or software
instructions stored within memory 79. As shown in Fig. 6, these software
instructions include, among other things, an operating system 81, a
30 communications control module 83, a direct communication module 85, an RRC
module 87, and a loopback module 89.
[0063]
The communications control module 83 is operable to handle (e.g.
generate, send and receive) control signals for controlling the connections between
20
the mobile communication device 3 and other mobile communication devices 3, the
base station 5, or the SS entity 11 (simulating a mobile communication device
and/or a base station). The communications control module 83 also controls the
separate flows of uplink data and control data that are to be transmitted to the
5 other mobile communication device 3, the base station 5, and the SS entity.
[0064]
The direct communication module 85 is operable to instruct the
communications control module 83 to set up a device-to-device communication
path (e.g. to support a ProSe based relaying functionality).
10 [0065]
The RRC module 87 is operable to handle (e.g. generate, send and receive)
control signals formatted according to the RRC protocol. The RRC module 87 is
also operable to identify in an RRC signalling message received from the SS entity
11 information identifying any EPS bearer of the mobile communication device 3
15 to be associated with a loopback function.
[0066]
The loopback module 89 is operable to manage (e.g. setup, modify,
terminate) communication bearers for looping back to the corresponding module of
the SS entity 11 (i.e. the loopback module 67) and thereby facilitating monitoring
20 data units sent/received by the mobile communication device 3.
[0067]
(Operation)
A more detailed description will now be given (with reference to Fig. 7 and
Fig. 8) of testing a mobile communication device 3 implementing proximity based
25 services.
[0068]
Fig. 7 illustrates schematically a test environment according to an
embodiment of the invention for verifying compatibility of a mobile
communication device 3 with the communication system 1 illustrated in Fig. 1.
30 [0069]
In particular, testing of the mobile communication device 3 is shown.
Some of the mobile communication device's 3 bearers that are not associated with
the relay function are connected to the loopback function of the mobile
communication device 3 whilst, in the example of Fig. 7, bearers related to the
21
relaying function operate independently as if the test mode was not activated in the
mobile communication device 3.
[0070]
The ability to apply selective loop-back in which the normal operation of
5 some bearers are maintained whilst others are tested using loop-back functionality
is achieved by using dedicated identifiers to individually specify the EPS bearers
according to their identity (e.g. the EPS bearer identity as specified in TS 24.301 -
9.3.2).
[0071]
10 A possible, purely exemplary, implementation of this new identification
information is given in 1 below:
[table 1]
8
EBI
(7)
EBI
(15)
7
EBI
(6)
EBI
(14)
6
EBI
(5)
EBI
(13)
5
EBI
(4)
EBI
(12)
4
EBI
(3)
EBI
(11)
3
EBI
(2)
EBI
(10)
2
EBI
(1)
EBI
(9)
1
EBI
(0)
EBI
(8)
[0072]
15 As can be seen, Table 1 shows sixteen EPS bearers each having an
associated EPS Bearer Identity (EBI). The respective EBIs can be identified
using two octets (bytes) of an information element for identifying the individual
bearers for testing. For example, selective loopback functionality may be
implemented by setting the bit corresponding to the EBI of the EPS bearer, for
20 which a loopback function needs to be activated, to an appropriate value (e.g. ' 1 ' ,
when ' 1 ' indicates loopback for the EPS bearer identified by the bit representing
that EBI).
[0073]
Since the above indication comprises a relatively low amount of
25 information, it would be beneficial to include it in a signalling message sent to the
mobile communication device 3 for activating the loopback functionality for the
selected EPS bearer.
octet 1
octet 2
22
[0074]
For example, in this embodiment, the EBI is included in a two octet
information element (IE) in a loop-back control message for activating /
deactivating loop-back functionality for specific EPS bearers (e.g. CLOSE UE
5 TEST LOOP and/or an OPEN UE TEST LOOP message), which may be transmitted
in the appropriate NAS message using appropriate RRC signalling.
[0075]
In a modification to this embodiment, a loopback mode may be applied
based on Access Point Name (APN). In this case, the APN to which the loopback
10 mode is to be applied (or to which the loopback mode is not to be applied) is
indicated to the mobile communications device 3 (i.e. instead of or in addition to
an indication of any EPS bearers as described above). In this case, the SS entity
11 may provide an indication of a particular APN by identifying the default bearer
for that APN (i.e. setting the bit corresponding to that bearer to the value
15 representing loopback activation). When the mobile communications device 3
receives the indication of (a default bearer for) an APN, the mobile
communications device 3 applies loopback functionality to the indicated default
EPS bearer and any dedicated EPS bearer(s) associated with that APN.
[0076]
20 Fig. 8 is a timing diagram illustrating the way in which the test system
entity (SS entity) 1 1 controls the activation and deactivation of a loopback
connection for a mobile communication device 3.
[0077]
Initially, in step S601, the mobile communication device 3 initiates an
25 attach procedure and indicates that it is trying to establish a PDN connection with
the core network 7. This procedure is carried out by the mobile communication
device 3 (using its RRC module 87) generating and sending (via the transceiver
circuit 71) to the SS entity 1 1 an appropriately formatted ATTACH REQUEST
message, including in this message a 'PDN Connectivity Request' as well. It will
30 be appreciated that the mobile communication device 3 might have intended to
send this message to a network entity (e.g. the MME 9) different from the SS entity
11.
[0078]
However, since in this embodiment a compliance test is to be performed,
23
the SS entity 11 generates and transmits (using its RRC module 65 and transceiver
circuit 51) an ACTIVATE TEST MODE message embedded in a suitable downlink
RRC message for transferring non-RRC messages (e.g. a 'DLInformationTransfer
message') to the mobile communication device 3 (at step S603) to activate the test
mode in the mobile communication device 3 prior to any bearer activation.
Rather than use one of the three conventional test modes (A, B or C) by setting the
appropriate IE (e.g. the "UE test loop mode" IE) to the value associated with that
test mode, a different value may be used to initiate a new test mode for use with
selective EPS bearer loop-back testing functionality. However, it will be
appreciated that one of the conventional test modes (A, B, or C) may also be
associated with the new test mode for use with selective EPS bearer loop-back
testing functionality. This may be achieved, for example, by including an
appropriate information element, in the RRC message and/or the non-RRC
message, specifying the modified use of the conventional test mode indicated in
that message.
[0079]
In step S605, in response to the preceding message, the mobile
communication device 3 generates and transmits (using its RRC module 87 and
transceiver circuit 71) an ACTIVATE TEST MODE COMPLETE message
embedded in an appropriate uplink transfer RRC message (e.g. an
'ULInformationTransfer' message) sent to the SS entity 11 to confirm that
activation of the test mode was successful.
[0080]
As indicated generally at S607, the mobile communication device 3 is now
in the test mode.
[0081]
Next, as shown generally at S609, the SS entity 1 1 (acting as or liaising
with a corresponding network entity) performs the necessary actions to
accommodate the mobile communication device's 3 request in step S601. As a
result of this step, the mobile communication device 3 establishes an active EPS
bearer with the SS entity 11 (although the mobile communication device 3 might
recognize this as a default and/or dedicated EPS bearer with the PGW 10).
[0082]
In step S611, the SS entity 11 generates and transmits (using its RRC
24
module 65 and transceiver circuit 51) a CLOSE UE TEST LOOP message
embedded in a, for example, a 'DLInformationTransfer' RRC message (generated
by its RRC module 65) to enter the mobile communication device 3 into test loop
mode. The SS entity 11 indicates the same value for the UE test loop mode IE
that was used in step S603. In this embodiment, the SS entity 11 also includes in
this message, e.g. as described above with respect to Table 1, an information
element identifying the EBI(s) for which a selective loopback function should be
applied by the mobile communication device 3.
[0083]
In step S613, the mobile communication device 3 generates and transmits
(using its RRC module 87 and transceiver circuit 71) a CLOSE UE TEST LOOP
COMPLETE message (e.g embedded in an 'ULInformationTransfer' RRC message)
to the SS entity 11 in order to confirm that loopback entities for the selected EPS
bearer(s) have been created and loop back (via its loopback module 89) has been
activated for the identified (selected) EPS bearers.
[0084]
As indicated at S615, the mobile communication device 3 is operable to
setup its loopback function according to the information received (in step S611) in
the 'EPS Bearer ID' IE from the SS entity 11. From this point and until
deactivation of the loopback function, the EPS bearer(s) indicated by the SS entity
11 are terminated in the loopback module 89, whilst termination of other bearers
remains unmodified (e.g. in the direct communication module 85 and/or the
communications control module 83).
[0085]
In step S617, the SS entity 1 1 generates and transmits (using its RRC
module 65 and transceiver circuit 5 1) an OPEN UE TEST LOOP message to the
mobile communication device 3 (e.g, embedded in a 'DLInformationTransfer' RRC
message), which causes the mobile communication device 3 to deactivate its test
loop entities.
[0086]
In step S619, the mobile communication device 3 generates and transmits
(using its RRC module 87 and transceiver circuit 71) an OPEN UE TEST LOOP
COMPLETE message to the SS entity 1 1 (e.g. embedded in an
'ULInformationTransfer' RRC message) to confirm that deactivation of the test
25
loop entities has been successful.
[0087]
As indicated at S621, the UE test loop is now successfully deactivated.
[0088]
In step S623, the SS entity 11 generates and sends (using its RRC module
65 and transceiver circuit 51) to the mobile communication device 3 a
DEACTIVATE TEST MODE message (e.g. embedded in a
'DLInformationTransfer' RRC message). The purpose of this procedure is to
deactivate UE test mode and return the UE to normal operation as per the prior art.
[0089]
In step S625, a DEACTIVATE TEST MODE COMPLETE is sent by the UE
to the SS (e.g. embedded in an 'ULInformationTransfer' RRC message) to confirm
completion of the deactivation of the UE test mode. In step S627, the UE exited
test mode.
[0090]
A clear benefit of the above proposal is to allow the possibility to evaluate
new functions prior to releasing a mobile communication device (or other user
equipment) to the market. This method could also be used with existing services
such as the services provided via the IP Multimedia Subsystem (IMS). The
proposal makes it possible to define any multi- service test case (TC)
configuration for verifying compliance with LTE and/or e.g. IMS services, while
other data services (e.g. internet) are looped back to the SS entity 11.
[0091]
(Modifications and Alternatives)
Detailed embodiments have been described above. As those skilled in the
art will appreciate, a number of modifications and alternatives can be made to the
above embodiments whilst still benefiting from the inventions embodied therein.
By way of illustration, only a number of these alternatives and modifications will
now be described.
[0092]
In the above embodiments, two mobile communication devices were
allowed to establish a relayed or other direct or locally routed connection with
each other. However, as those skilled in the art will appreciate, such connections
may be established between three or more mobile communication devices, so that
26
the users of the mobile communication devices may be connected together in a
conference call setup.
[0093]
In the above embodiments, the mobile communication devices are cellular
telephones. However, other types of user devices such as, for example, MTC
(Machine Type Communication) devices, smartphones, personal digital assistants,
laptop computers, web browsers, etc. could be used.
[0094]
Although the relayed or other direct communication paths between mobile
communication devices within the same communications network have been
described, the proximity based communication paths according to the invention
may be set up between mobile communication devices located in different
communications networks. In this case, the mobility management entities (and in
some cases the base stations) for the respective mobile communication devices are
also located in different networks. The SS entity may be operable to test such
scenarios as well.
[0095]
In the above embodiments, relayed communication paths which use an LTE
technology (i.e. the same communications technology that is used between the base
station and the relaying mobile communication device) have been described.
However, it will be appreciated that a communication path may be relayed using
any communications technology, for example, Wi-Fi, Bluetooth, etc. (irrespective
of the communications technology used between the base station and the relaying
mobile communication device).
[0096]
In the above description of step S617, the SS entity 1 1 generates and
transmits an OPEN UE TEST LOOP message which causes the mobile
communication device 3 to completely deactivate its test loop entities. However,
it will be appreciated that the test loops entities may be deactivated selectively,
e.g. by including the EBI(s) of those EPS bearers that are to be removed from the
loopback module 89 of the mobile communication device 3, whilst keeping other
already looped EPS bearers unchanged. For example, the selective loopback
functionality may be deactivated for any particular EPS bearer by setting the EBI
of that EPS bearer to a value the same as or different from the value associated
27
with loopback activation (e.g.: a ' 0 ' for deactivation when ' 1 ' indicates activation;
or a ' 1' to change the state of an EPS bearer for which loopback has previously
been activated to a state in which loopback is deactivated).
[0097]
In the above description, the system simulator entity 11 is described as a
being used for compliance testing of a mobile communication device 3. However,
it will be appreciated that the system simulator entity 11 may also be used for
testing a base station 5 handling (and/or the PGW 10 terminating) the non-relaying
EPS bearers for mobile communication devices 3 involved in proximity based
services.
[0098]
In the above description, the system simulator entity 11 is described as a
standalone entity. However, it will be appreciated that the system simulator
entity 11 may be implemented as part of another apparatus. For example, the
system simulator entity 11 may form part of the base station 5. In this case, it
will be appreciated that it will be advantageous for the base station 5 to control the
loopback function of the mobile communication device 3 for testing compliance
and/or performance of proximity based services (e.g. before activating such
services for that mobile communication device 3).
[0099]
In an alternative embodiment, the loopback mode may be selectively
applied for any given functionality and/or service of the mobile communication
device. In this case, the SS entity provides an identification of any selected
functionality and/or service to be associated with the loopback module (instead of,
or in addition to an identification of any EPS bearer) and the mobile
communication device (e.g. its loopback module 89) applies the loopback function
to the identified functionality and/or service.
[0100]
It will also be appreciated that the mobile communication device may be
configured to restrict application of the loopback function to certain
functionalities and/or services by specification. In this case, the mobile
communication device may apply the loopback function to only those
functionalities and/or services that are not restricted, irrespective of the
identification of functionalities and/or services provided by the SS entity.
28
[0101]
In the above description, the system simulator entity 11 and the mobile
communication devices 3 are described for ease of understanding as having a
number of discrete functional components or modules. Whilst these modules may
be provided in this way for certain applications, for example, where an existing
system has been modified to implement the invention, in other applications, for
example in systems designed with the inventive features in mind from the outset,
these modules may be built into the overall operating system or code, and so these
modules may not be discernible as discrete entities.
[0102]
In the above embodiments, a number of software modules were described.
As those skilled in the art will appreciate, the software modules may be provided
in a compiled or un-compiled form and may be supplied to the mobility
management entity, to the base station, or to the mobile communication device as a
signal over a computer network, or on a recording medium. Further, the
functionality performed by part or all of this software may be performed using one
or more dedicated hardware circuits. However, the use of software modules is
preferred as it facilitates the updating of the mobility management entity 9, the
base stations 5 and the mobile communication devices 3 in order to update their
functionalities.
[0103]
Various other modifications will be apparent to those skilled in the art and
will not be described in further detail here.
[0104]
(Glossary of 3GPP terms)
D2D - Device to Device
eNB - Evolved NodeB, E-UTRAN base station
EPC - Evolved Packet Core
EPS - Evolved Packet System
E-UTRA - Evolved UMTS Terrestrial Radio Access
E-UTRAN - Evolved UMTS Terrestrial Radio Access Network
HSS - Home Subscriber Server
LB - Loopback
LTE - Long Term Evolution (of UTRAN)
29
MME - Mobility Management Entity
NAS - Non-Access-Stratum
OAM - Operation And Maintenance
P-GW - PDN Gateway
ProSe - Proximity-based Services
(E-)RAB - (EPS-) Radio Access Bearer
RRC - Radio Resource Control
SI-MME - SI for the control plane
Sl-U - SI for the user plane
S-GW - Serving Gateway
SS - System Simulator
TFT - Traffic Flow Template
UE - User Equipment
UMTS - Universal Mobile Telecommunications System
[0105]
Various other modifications will be apparent to those skilled in the art and
thus will not be described in further detail here.
[0106]
This software can be stored in various types of non-transitory computer
readable media and thereby supplied to computers. The non-transitory computer
readable media includes various types of tangible storage media. Examples of the
non-transitory computer readable media include a magnetic recording medium
(such as a flexible disk, a magnetic tape, and a hard disk drive), a magneto-optic
recording medium (such as a magneto-optic disk), a CD-ROM (Read Only
Memory), a CD-R, and a CD-R/W, and a semiconductor memory (such as a mask
ROM, a PROM (Programmable ROM), an EPROM (Erasable PROM), a flash ROM,
and a RAM (Random Access Memory)). Further, the program can be supplied to
computers by using various types of transitory computer readable media.
Examples of the transitory computer readable media include an electrical signal,
an optical signal, and an electromagnetic wave. The transitory computer readable
media can be used to supply programs to computer through a wire communication
path such as an electrical wire and an optical fiber, or wireless communication
path.
[0107]
30
This application is based upon and claims the benefit of priority from
United Kingdom patent application No.1305821.9 filed on 28 March, 2013, the
disclosure of which is incorporated herein in its entirety by reference.
Reference Signs List
[0108]
I communication system
3, 3-1, 3-2, 3-3 mobile communication device
5, 5-1, 5-2 E-UTRAN base station (eNB)
7 core network
8 serving GW (S-GW)
9 mobility management entity (MME)
10 PDN GW (P-GW)
II system simulator (SS) entity
12 endpoint
51 transceiver circuit
53 antenna
55 user interface
57 controller
59 memory
61 operating system
63 communications control module
65 radio resource control (RRC) module
66 simulation module
67 loopback module
71 transceiver circuit
73 antenna
75 user interface
77 controller
79 memory
81 operating system
83 communications control module
85 direct communication module
87 radio resource control (RRC) module
89 loopback module
WE CLAIM:
31
[Claim 1] A communication device for communicating with a
communication network test device operable to monitor
operation of said communication device, the
communication device comprising:
means for operating a plurality of communication
bearers associated with said communication device;
means for determining a subset comprising at least one
communication bearer, selected from said plurality of
communication bearers, to be used when performing a
test and not comprising at least one other
communication bearer of said plurality of
communication bearers; and
means for communicating with the communication
network test device in pursuance of a test in which
each communication bearer in said subset is used and
each communication bearer not in said subset is not
used.
[Claim 2] The communication device according to claim 1 ,
further comprising means for receiving a message, from
said communication network test device, the message
comprising data identifying each communication bearer
in said subset, wherein said determining means is
operable to determine said subset based on said data
identifying each communication bearer in said subset.
[Claim 3] The communication device according to claim 1,
further comprising means for receiving a message, from
said communication network test device, the message
comprising data identifying each communication bearer
not in said subset, wherein said determining means is
operable to determine said subset based on said data
32
identifying each communication bearer not in said
subset.
[Claim 4] The communication device according to claim 2 or 3,
wherein said message comprises a bit pattern with at
least one respective bit associated with each
communication bearer of said plurality of
communication bearers associated with said
communication device.
[Claim 5] The communication device according to claim 4,
wherein each said bit is set to a predetermine value if
said communication bearer is in said subset.
[Claim 6] The communication device according to claim 2 or 3,
wherein said message comprises a bit pattern with at
least one respective bit associated with a default
communication bearer of said plurality of
communication bearers associated with said
communication device.
[Claim 7] The communication device according to claim 6,
wherein each said bit is set to a predetermine value if
said default communication bearer and any associated
communication bearer is in said subset.
[Claim 8] The communication device according to any of claims 2
to 7, wherein said message comprises a bearer
i d e n t i f i e r (e.g. an Evolved Packet System, EPS, Bearer
ID or EBI) for each communication bearer of said
subset.
[Claim 9] The communication device according to any of claims 2
to 8, wherein said message comprises a Non-Access
33
Stratum, NAS, message.
[Claim 10] The communication device according to claim 9
wherein said NAS message is embedded in at least one
Radio Resource Control, RRC, message.
[Claim 1 1] The communication device according to claim 10,
wherein said at least one message comprises a downlink
information transfer message.
[Claim 12] The communication device according to any of claims 1
to 11, wherein said test is a loop-back test.
[Claim 13] A communication system comprising the communication
device of any of claims 1 to 12, and the communication
network test device.
[Claim 14] A method performed by a communication device for
communicating with a communication network test
device operable to monitor operation of said
communication device, the method comprising:
e s t a b l i s h i n g a plurality of communication bearers
associated with said communication device;
determining a subset comprising at least one
communication bearer, selected from said plurality of
communication bearers, to be used when performing a
test and not comprising at least one other
communication bearer of said plurality of
communication bearers; and
communicating with the communication network test
device in pursuance of a test in which each
communication bearer in said subset is used and each
communication bearer not in said subset is not used.
34
[Claim 15] A method performed by a communication network test
device for monitoring operation of a communication
device, the method comprising:
e s t a b l i s h i n g communication with said communication
device;
identifying each of a plurality of communication
bearers associated with said communication device;
determining a subset comprising at least one
communication bearer, selected from said plurality of
communication bearers, to be used when performing a
test and not comprising at least one other
communication bearer of said plurality of
communication bearers; and
i n i t i a t i n g a test in which each communication bearer in
said subset is used and each communication bearer not
in said subset is not used.
[Claim 16] A n o n - t r a n s i t o r y computer-readable medium storing a
control program for causing a computer to perform a
process of c o n t r o l l i n g the communication device of any
of claims 1 to 12.