FIELD OF INVENTION
[0001] The present subject matter relates to communication networks and, particularly,
but not exclusively, to establishing a radio link in universal mobile telecommunication system
(UMTS).
BACKGROUND
[0002] Universal mobile telecommunication system (UMTS) is a third generation (3G)
mobile communication system providing high quality voice and data services to users around the
world. UMTS evolved from global system for mobile (GSM) standard and offers high bandwidth
speed for different services such as voice calls, data services, mobile internet, video calling, and
the like.
[0003] Service providers offer several services to the user over a network based on
UMTS. For example, service providers offer services such as voice calls, data services,
messaging services, mobile TV, video calling, internet browsing, and the like, and charge the
user according to a subscription plan availed by the user. The user, in order to avail these
services, needs to establish a radio link with the network. The radio link is a dedicated path
between the user and the network and determines the connectivity experience provided to the
user by the service provider. For example, different radio links may have different levels of
quality of service (QoS) associated with them. The network may determine the transmission
power and other parameters associated with the radio links based upon the service availed by the
user.
[0004] For availing any of these services, the user sends a request to the network through
a user equipment (UE) for establishing a dedicated radio link over which the user can avail these
services. Based upon the request from the user, the network initiates certain protocols for
establishing the dedicated radio link between the user and the network. After completion of these
protocols, the dedicated radio link is established between the UE and the Node B.
[0005] The network handles such requests from all the UE, that are either already
registered or attempting to register with the network, trying to avail the services offered by the
service provider over the network. Due to advancement in wireless technology and continually
developing standards, the network upgrades several network elements time to time for providing
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better services to the user. In order to upgrade, the network needs to reset some network
elements, thereby leading to teardown of the dedicated radio links established between the UE
and the network. In general, reset of network elements is performed during maintenance period,
generally during night time, when the frequency of users availing the network services is low.
However, certain network elements, such as the Node B may go for a reset due to a software or
hardware error.
[0006] As soon as the network elements are restored to their full potential, several UE
simultaneously try to re-establish the radio link between the UE and the network, thereby
increasing the burden on the network resources. Simultaneous requests from the UE might lead
to a system overload resulting in instability in the network.
SUMMARY
[0007] This summary is provided to introduce concepts related to establishing a radio
link in universal mobile telecommunication systems. This summary is not intended to identify
essential features of the claimed subject matter nor is it intended for use in determining or
limiting the scope of the claimed subject matter.
[0008] In one implementation, a method for establishing a radio link in a communication
network is described. The method includes generating a dedicated channel setup request message
for establishing a plurality of asynchronous transfer mode (ATM) adaption layer 2 (AAL2)
paths, where the dedicated channel setup request message comprises a plurality of SUGR fields.
Each SUGR field includes a binding identity and each binding identity corresponds to an AAL2
path. Further, the method includes sending the dedicated channel setup request message to a
Node B and, subsequently, receiving a dedicated channel setup response message from the Node
B.
[0009] In one implementation, a method for processing a dedicated channel setup request
message in a Node B is described. The method includes receiving a dedicated channel setup
request message from an RNC, where the dedicated channel setup request message comprises a
plurality of SUGR fields, and where each SUGR field includes a binding identity corresponding
to an AAL2 path. Further, the method includes extracting one or more of the plurality of SUGR
fields from the dedicated channel setup request message. Based on the binding identities
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specified in the SUGR field, the plurality of AAL2 paths are established. The method further
includes sending a dedicated channel setup response message.
[0010] In another implementation, a radio network controller (RNC) for establishing a
radio link in a communication network is described. The RNC includes a processor and a setup
module coupled to the processor. The setup module is configured to generate a dedicated channel
setup request message for establishing a plurality of AAL2 paths, where the dedicated channel
setup request message comprises a plurality of SUGR fields, and where each SUGR field
includes a binding identity corresponding to an AAL2 path.
[0011] In another implementation, a Node B for processing a dedicated channel setup
request message is described. The Node B includes a processor and a processing module coupled
to the processor. The processing module is configured to extract one or more of a plurality of
SUGR fields of a dedicated channel setup request message, where each SUGR field includes a
binding identity corresponding to an AAL2 path. Further, the processing module is configured to
establish a plurality of AAL2 paths based on the dedicated channel setup request.
[0012] In accordance with another implementation of the present subject matter, a
computer-readable medium having embodied thereon a computer program for executing a
method of establishing a radio link in a communication network is described. The method
comprises generating a dedicated channel setup request message for establishing a plurality of
AAL2 paths, where the dedicated channel setup request message comprises a plurality of SUGR
fields. Each SUGR field includes a binding identity and each binding identity corresponds to an
AAL2 path. Further, the method includes sending the dedicated channel setup request message to
a Node B and, subsequently, receiving a dedicated channel setup response message from the
Node B.
[0013] In accordance with another implementation of the present subject matter, a
computer-readable medium having embodied thereon a computer program for executing a
method of processing a dedicated channel setup request message in a Node B. The method
comprises receiving a dedicated channel setup request message from an RNC, where the
dedicated channel setup request message comprises a plurality of SUGR fields, and where each
SUGR field includes a binding identity corresponding to an AAL2 path. Further, the method
includes extracting one or more of the plurality of SUGR fields from the dedicated channel setup
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request message. Based on the binding identities specified in the SUGR field, the plurality of
AAL2 paths are established. The method further includes sending a dedicated channel setup
response message.
BRIEF DESCRIPTION OF THE FIGURES
[0014] The detailed description is described with reference to the accompanying figures.
In the figures, the left-most digit(s) of a reference number identifies the figure in which the
reference number first appears. The same numbers are used throughout the figures to reference
like features and components. Some embodiments of system and/or methods in accordance with
embodiments of the present subject matter are now described, by way of example only, and with
reference to the accompanying figures, in which:
[0015] Figure 1 illustrates an exemplary network environment implementation for
establishing a radio link in a communication system, according to an embodiment of the present
subject matter;
[0016] Figure 2(a) schematically illustrates network entities for establishing a radio link
in a communication network, in accordance with an embodiment of the present subject matter;
[0017] Figure 2(b) is a call flow diagram indicating procedures for establishing a radio
link in a communication network, according to an embodiment of the present subject matter;
[0018] Figure 3 illustrates a method for establishing a radio link in a communication
network, in accordance with an embodiment of the present subject matter; and
[0019] Figure 4 illustrates a method for establishing AAL2 paths in a communication
network, in accordance with an embodiment of the present subject matter.
[0020] In the present document, the word "exemplary" is used herein to mean "serving as
an example, instance, or illustration." Any embodiment or implementation of the present subject
matter described herein as "exemplary" is not necessarily to be construed as preferred or
advantageous over other embodiments.
[0021] It should be appreciated by those skilled in the art that any block diagrams herein
represent conceptual views of illustrative systems embodying the principles of the present
subject matter. Similarly, it will be appreciated that any flow charts, flow diagrams, state
transition diagrams, pseudo code, and the like represent various processes which may be
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substantially represented in computer readable medium and so executed by a computer or
processor, whether or not such computer or processor is explicitly shown.
DESCRIPTION OF EMBODIMENTS
[0022] The present subject matter relates to establishing a radio link in universal mobile
telecommunication system. The methods can be implemented in various communication devices
communicating through various networks. The communication devices that can implement the
described method(s) include, but are not limited to, cellular phones, smart phones, personal
digital assistants (PDAs), portable computers, desktop computers, wireless data cards, servers
and the like. The communication networks in which the described method(s) can be implemented
include, but are not limited to, Universal Mobile Telecommunications System (UMTS) network
utilizing Wideband Code Division Multiple Access (W-CDMA).
[0023] In communication networks, a service provider offers several services, such as
voice calls, data services, messaging services, mobile TV, video calling, internet browsing, and
the like to a user over the communication network. The user avails these services through a user
equipment (UE), for example, a mobile phone, a smart phone, a personal digital assistant (PDA),
a laptop, personal computer, a wireless data card, and the like registered with the service
provider. For availing these services, a dedicated connection needs to be established between the
UE and the communication network. The UE interacts with the communication network through
a radio link (RL) between the UE and a network element, such as a Node B over an air interface.
For example, the UE interacts with the Node B over a Uu interface in a communication network
based on UMTS standard.
[0024] Typically, for establishing the RL, the UE sends a radio resource control (RRC)
connection setup request to a radio network controller (RNC) present in the network. The RNC is
responsible for radio resource management of network resources, such as transmission power,
channel allocation, data rates, handover criteria, modulation scheme, error coding scheme and
the like. Among other functions, the RNC is also configured to manage another network element,
the Node B, present in the radio access network (RAN) of the UMTS. The Node B comprises a
transceiver for transmitting and receiving radio signals from the UE. The RNC manages the
Node B through a signaling protocol over an interface. In one implementation, the RNC manages
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the Node B through a Node B application part (NBAP) signaling protocol carried over an IuB
interface. The NBAP protocol is a radio network control plane protocol of the IuB interface.
[0025] For example, in order to establish a voice call over the network or for registering
itself with the network, a UE sends a RRC connection setup request to a RNC for establishing a
RL between the UE and the Node B. In another case, the UE may send the RRC connection
setup request for establishing the RL for availing internet services through a web browser
application running on the UE. In yet another case, the UE may send the RRC connection setup
request for registering itself with the network. Further, the quality of service associated with the
RL depends on the category of the UE, the subscription plan associated with the UE, and the
kind of RRC connection request.
[0026] Further, based on the RRC connection request from the UE, the RNC may provide
the RL and manage the network resources accordingly. For the purpose, the RNC determines
several parameters such as transmission power, quality of service, bit rate, and the like associated
with the RL. The RNC then sends a RL setup request message to the Node B for establishing an
AAL2 path between the RNC and the Node B for carrying signaling information related to the
radio link. In one case, the RNC sends the RL setup request to the Node B using the NBAP
protocol over the IuB interface. In one implementation, the IuB interface between the RNC and
the Node B is based on ATM backhaul, as would be understood by a person skilled in the art.
Subsequently, the Node B sends a RL setup response message containing a binding identity
corresponding to the AAL2 path to the RNC. The binding identity is used for mapping the UE
with the AAL2 path for transmitting signaling information related to the radio link established
between the UE and the Node B. Using the binding identity, the RNC and the Node B can
identify the AAL2 path which is to be associated with the UE. Further, the binding identity also
acts as a linking identity between the NBAP and an access link control application part (ALCAP)
protocol of the IuB interface.
[0027] Further, the RNC uses the ALCAP protocol, present in a transport network control
plane of the IuB interface, for establishing the AAL2 path. For the purpose, the RNC sends an
access link control application part establish request (ALCAP-ERQ) message to the Node B. A
service user generated reference (SUGR) field in the ALCAP-ERQ message contains the binding
identity corresponding to the AAL2 path which is to be established. The Node B sends an access
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link control application part establish confirm (ALCAP-ECF) message to the RNC, in response
to the ALCAP-ERQ message, confirming the establishment of the AAL2 path and associates the
binding identity specified in the incoming ALCAP-ERQ with the UE. The RNC, upon successful
exchange of these messages, sends a RRC connection setup response to the UE, thereby
signaling to the UE, to establish the radio link with the communication network. Evidently, the
RNC and the Node B exchange at least four messages for establishing the radio link between the
UE and the Node B, thereby increasing the setup time for establishing the radio link. The above
ALCAP (ERQ/ECF) procedure is repeated for each AAL2 bearer in the UMTS terrestrial radio
access network (UTRAN).
[0028] Typically, a large number of UE, registered with the service provider, exist and
communicate with the communication network through the Node B. Due to advancements in
wireless communication technology, several elements of the communication network are often
upgraded with new specifications for efficient management of network resources thereby
offering better quality of services to the user. However, updating the elements may cause certain
elements, such as the Node B, to reset. For example, the Node B may reset several times on
being upgraded to a new specification. In one case, the Node B may reset due to a bug in the
software. In another case, the Node B may reset several times during the day due to internal
technical error.
[0029] Resetting of the Node B may lead to a teardown of the radio link established
between the Node B and the UE present in the network. After getting reset, as soon as the Node
B becomes functional, several UE may simultaneously attempt to establish the radio link with
the network and may send the RRC connection setup request to the Node B. This is typically
known as a registration storm. The registration storm may lead to a lag in the NBAP protocol
between the RNC and the Node B, thereby leading to a significant delay in the RRC connection
setup procedure. This registration storm may overload the Node B and consequently lead to a lag
in the establishment of the radio link. Due to delay in the establishment of the radio link, the UE
may send repeated RRC connection setup requests after a certain timeout interval. Typically, the
timeout interval is configured in the UE by the RNC via Broadcast Channel. In a case where
multiple UE's send connection setup requests, the network receives a flurry of requests which
increases exponentially with time causing a snowball effect. As a result of the snowball effect,
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the Node B may reach an unrecoverable condition and may remain unavailable for a long time
thereby leading to a degraded level of quality of service provided to the user.
[0030] In one solution, known in the prior art, a call processing mailbox in the Node B is
monitored for a threshold value of requests. In one case, the threshold value of requests may be
understood as maximum number of RL setup requests that the Node B can handle. Upon
receiving an RL setup request from the RNC, the Node B monitors the status of the call
processing mailbox and determines whether to accept or reject the RL setup request. In one
implementation a software program in the Node B may be programmed to monitor and
determine the response of the call processing mailbox to the incoming RL setup requests. In one
implementation, the Node B may reject the RL setup request if it determines that the call
processing mailbox is above the threshold value of requests. In such a case, the Node B reverts
back to the RNC with a request failed message, for example, the Node B may send a
'misc_control_processing_overload = 114' request failed message to the RNC. Further, the RNC
sends a connection setup reject message, such as a RRC connection reject message, to the UE,
indicating connection setup failure. The RRC connection message specifies the wait time after
which the UE can retry for establishing the connection.
[0031] However, monitoring the call processing mailbox for handling the RL setup
request may lead to rejection of a high priority connection setup request. For example, the call
processing mailbox in the Node B, when above the threshold value, may reject a RL setup
request for an emergency call as the call processing mailbox is not provisioned to distinguish
between the RL setup requests. In another case, a UE, upon receiving the connection setup reject
message, may repeatedly try to establish connection and may send multiple connection requests
to the RNC, thereby leading to a flurry of RL setup requests at the Node B resulting in
overloading of the Node B. Thus, a degraded level of quality of service is provided to the user
leading to user dissatisfaction. Subsequent resets of the Node B may increase the maintenance
and operation costs of the network.
[0032] The present subject matter relates to establishing a radio link in universal mobile
telecommunication system. In an embodiment of the present subject matter, methods and
systems for establishing a radio link in universal mobile telecommunication system is described.
The present systems and methods for establishing a radio link involves utilizing pre-established
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AAL2 paths between the RNC and the Node B. Pre-establishment of AAL2 paths helps in
reducing the setup time for establishing the radio link between the UE and the Node B, thereby
resulting in better management of network resources and averting overloading of communication
network elements, such as the Node B.
[0033] In one implementation, the RNC establishes a pre-determined number of AAL2
paths between the RNC and the Node B. In another implementation, the RNC may also
determine a category of quality of service associated with each of these AAL2 paths. For
example, the RNC may establish 100 AAL2 paths supporting high bit rate transmission over the
network which may be utilized for supporting services, such as video calling, high speed internet
browsing, and mobile TV, which require high speed transmission over the network. In another
example, the RNC may establish 200 AAL2 paths supporting voice calls. Further, the RNC
generates binding identities, where each binding identity corresponds to each AAL2 path which
is to be established between the RNC and the Node B.
[0034] For the purpose, the RNC sends a new NBAP Dedicated Channel Setup DCHSetup
request message, hereinafter referred to as DCH setup request message, to the Node B for
establishing the AAL2 paths. The DCH setup request message contains service user generated
reference (SUGR) fields, where each SUGR field includes a binding identity corresponding to an
AAL2 path which is to be established. In one implementation, the RNC is provisioned to fill the
binding identities corresponding to the AAL2 paths which are to be established in the SUGR
fields. For example, the RNC may send a DCH setup request message for establishing 50 AAL2
paths between the RNC and Node B. Further, the DCH setup request message contains SUGR
fields containing the binding identities, say, 1 to 50 corresponding to each of the 50 AAL2 paths.
The binding identities corresponding to the AAL2 paths help in identifying one DCH each. Each
of the 50 AAL2 paths has a category of quality of service associated with them as determined by
the RNC.
[0035] In one implementation, the RNC sends the DCH setup request message as a part
of an initial setup procedure, between the RNC and the Node B, when the Node B becomes
functional after resetting. In another implementation, after the AAL2 paths have been established
during the initial setup procedure, the RNC may determine a threshold value for sending another
DCH setup request message. For instance, 50 AAL2 paths are established between the RNC and
11
the Node B during the initial setup procedure. The RNC may determine a threshold value, say, 30
for sending another DCH setup request message. Once 30 AAL2 paths are utilized within the
network, the RNC sends a DCH setup request message to the Node B for setting up more AAL2
paths.
[0036] The Node B, upon receiving the DCH setup request message, extracts the binding
identities corresponding to the AAL2 paths enlisted in the SUGR field. In one implementation,
the Node B is provisioned to store the binding identities in a list. Thus, the Node B and the RNC
have the same set of binding identities corresponding to an AAL2 path. Further, the Node B
sends a DCH setup response message to the RNC indicating the establishment of the AAL2
paths. Thus, the AAL2 paths established in the network are ready for use and may be used for
establishing the radio link between the UE and the Node B.
[0037] The RNC may receive a request, such as the RRC connection request for
establishing the radio link between the UE and the Node B. In one implementation, a user avails
the different services offered by the service provider through a UE registered with the service
provider. Registration of UE is done to ensure that no un-authorized UE gains access to the
network and generally involves authentication of registration details, such as identity number,
specific to the UE being authenticated. In order to avail the services, the UE sends the RRC
connection request message to the RNC for establishing the radio link between the UE and the
Node B. The RNC, through a predetermined algorithm, selects an AAL2 path, from amongst the
pool of already established AAL2 paths, to be provided for establishing the radio link between
the UE and the Node B. In one implementation, the RNC may select the AAL2 path based on a
subscription plan availed by the user. In another implementation, the RNC may determine the
AAL2 path based on the type of service requested by the user.
[0038] Subsequently, the RNC sends the RL setup request message containing the
binding identity corresponding to the AAL2 path to the Node B. The Node B processes the RL
setup request message and maps the UE with the binding identity specified in the RL setup
message thereby associating the UE with the AAL2 path already present in the network. The
Node B, then, sends the RL setup response message to the RNC, affirming the completion of
mapping of the UE and the AAL2 path. Further, the RNC sends the RRC connection response
message to the UE thereby signaling the UE to establish the radio link with the Node B. Thus,
12
the number of messages exchanged for establishment of the AAL2 path are reduced by half, i.e.,
only two messages are exchanged between the RNC and the Node B for setting up the AAL2
path, thereby reducing the setup time needed for establishing the dedicated connection. Further,
in case of teardown of AAL2 paths established in the network, the setup procedure for handling
the teardown would be carried out as done in conventional method.
[0039] The present subject matter, thus helps in reducing the setup time for establishing
the radio link between the UE and the Node B thereby leading to better handling of the network
resources and avoiding overloading of the network elements, such as the Node B. Establishment
of AAL2 paths in advance also helps in better handling of the connection requests from multiple
UE during registration storm, resulting in efficient management of network resources and better
level of quality of service being provided to the user. Further, fewer messages are exchanged
over the IuB interface between the RNC and the Node B thereby saving the additional processing
time in the RNC and the Node B.
[0040] The described methodologies can be implemented in hardware, firmware,
software, or a combination thereof. For a hardware implementation, the processing units can be
implemented within one or more application specific integrated circuits (ASICs), digital signal
processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices
(PLDs), field programmable gate arrays (FPGAs), processors, controllers, micro-controllers,
microprocessors, electronic devices, other electronic units designed to perform the functions
described herein, or a combination thereof. Herein, the term "system" encompasses logic
implemented by software, hardware, firmware, or a combination thereof.
[0041] For a firmware and/or software implementation, the methodologies can be
implemented with modules (e.g., procedures, functions, and so on) that perform the functions
described herein. Any machine readable medium tangibly embodying instructions can be used in
implementing the methodologies described herein. For example, software codes and programs
can be stored in a memory and executed by a processing unit. Memory can be implemented
within the processing unit or may be external to the processing unit. As used herein the term
"memory" refers to any type of long term, short term, volatile, nonvolatile, or other storage
devices and is not to be limited to any particular type of memory or number of memories, or type
of media upon which memory is stored.
13
[0042] In another firmware and/or software implementation, the functions may be stored
as one or more instructions or code on a computer-readable medium. Examples include
computer-readable media encoded with a data structure, and the computer-readable media
encoded with a computer program. The computer-readable media may take the form of an article
of manufacturer. The computer-readable media includes physical computer storage media. A
storage medium may be any available medium that can be accessed by a computer. By way of
example, and not limitation, such a computer-readable media can comprise RAM, ROM,
EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic
storage devices, or any other medium that can be used to store desired program code in the form
of instructions or data structures and that can be accessed by a computer; disk and disc, as used
herein, includes compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy
disk and Blu-ray disc where disks usually reproduce data magnetically, while discs reproduce
data optically with lasers. Combinations of the above should also be included within the scope of
the computer-readable media.
[0043] It should be noted that the description and figures merely illustrate the principles
of the present subject matter. It will thus be appreciated that those skilled in the art will be able to
devise various arrangements that, although not explicitly described or shown herein, embody the
principles of the present subject matter and are included within its spirit and scope. Further, all
examples recited herein are principally intended expressly to be only for pedagogical purposes to
aid the reader in understanding the principles of the present subject matter and the concepts
contributed by the inventor(s) to furthering the art, and are to be construed as being without
limitation to such specifically recited examples and conditions. Moreover, all statements herein
reciting principles, aspects, and embodiments of the present subject matter, as well as specific
examples thereof, are intended to encompass equivalents thereof.
[0044] It will also be appreciated by those skilled in the art that the words during, while,
and when as used herein are not exact terms that mean an action takes place instantly upon an
initiating action but that there may be some small but reasonable delay, such as a propagation
delay, between the initial action and the reaction that is initiated by the initial action.
Additionally, the word “connected” and “coupled” is used throughout for clarity of the
description and can include either a direct connection or an indirect connection.
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[0045] The manner in which the systems and the methods for establishing a radio link in
universal mobile telecommunication system shall be implemented has been explained in details
with respect to the Figures 1, 2(a), 2(b), 3, and 4. While aspects of described systems and
methods for establishing a radio link in universal mobile telecommunication system can be
implemented in any number of different computing systems, transmission environments, and/or
configurations, the embodiments are described in the context of the following exemplary
system(s).
[0046] Figure 1 illustrates a communication network environment 100 implementing
communication devices 102, in accordance with an embodiment of the present subject matter.
[0047] The communication network environment 100 comprises a plurality of
communication devices 102-1, 102-2, 102-3,…102-N (collectively referred to as communication
devices 102, and individually referred to as communication device 102, hereinafter) connected to
each other through a communication network 104.
[0048] The communication devices 102 may be defined as User Equipments (UEs) used
by users to communicate with each other. Examples of the communication devices 102 may
include, without limitation, mobile phones, landline phones, desktop computers, hand-held
devices, laptops or other portable computers, network computers, and the like. Each of the
communication devices 102 work on a communication protocol as defined by the
communication network to which the communication device 102 is coupled.
[0049] The communication network 104 may be a wireless network, or a combination of
wired and wireless network. The communication network 104 can be a collection of individual
networks, interconnected with each other and functioning as a single large network (e.g., the
internet or an intranet). Examples of such individual networks include, but are not limited to, 3rd
Generation Partnership Project (3GPP), Long Term Evolution (LTE), and the like. Although the
description herein is with reference to universal mobile telecommunication system (UMTS)
network, the methods and the systems may be implemented in other communicating networks,
albeit with a few variations, as will be understood by a person skilled in the art. Further,
depending on the technology, the communication network 104 includes various network entities,
such as gateways, routers; however, such details have been omitted for ease of understanding.
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[0050] Further, the communication devices 102 are configured to interact with each other
over the communication network 104 using network routed communication links 106-1, 106-2,
106-3, …, 106-N, hereinafter collectively referred to as the network routed communication links
106. The network routed communication links 106 may be understood as communication links
used in conventional communication where the communication devices 102 interact with each
other or the communication network 104 through network resources.
[0051] The communication network 104 further comprises a radio network controller
(RNC) 108 and a Node B 110. The RNC 108 is responsible for managing network resources and
interacts with the Node B 110 over an IuB interface using a NBAP protocol. Additionally, the
RNC 108 is configured to establish a radio link (RL) between the communication device 102 and
the Node B 110 over which a user avails several services as described earlier. The RNC 108 is
provisioned to establish AAL2 paths between the RNC 108 and the Node B 110 for carrying
signaling information related to the RL. In one implementation, the RNC 108 may be configured
for establishing a pre-determined number of dedicated channels (DCH) between the RNC 108
and the Node B.
[0052] In one implementation, the AAL2 paths are used for carrying signaling
information, between the RNC 108 and the Node B 110, associated with the RL between the
communication device 102 and the Node B 110. For instance, the AAL2 paths may carry
signaling information, such as transmission power, bit rate, handover signaling information and
the like associated with the radio link. Each of the AAL2 path is identified by a binding identity
which is determined by the RNC 108. For establishing the AAL2 paths, a setup module 112 of
the RNC 108 may be configured for sending a DCH setup request message to the Node B 110. In
one implementation, the DCH setup request message specifies the number of AAL2 paths that
are to be established. In another implementation, the RNC 108 may be configured to determine a
category of quality of service (QoS) associated with each of the AAL2 pathsDCH. Further, the
DCH setup request message contains the binding identities associated with each of the AAL2
paths.
[0053] In one implementation, the RNC 108 sends the DCH setup request message as a
part of the initial setup procedure between the RNC 108 and the Node B 110 after the Node B
110 has been reset. In another implementation, the RNC 108 may determine a threshold value for
16
sending the DCH setup request message. For example, the RNC 108 may establish 100 AAL2
paths during the initial setup procedure. Further, the RNC 108 may determine a threshold value,
say, 75. Upon utilization of 75 AAL2 paths, the RNC 108 may be configured to send another
DCH setup request message to the Node B 110. In another implementation, the RNC 108 may be
configured to operate conventionally as described earlier, after all the AAL2 paths have been
utilized. For example, during night time when the frequency of RRC connection requests from
the UE's is low, the RNC 108 may be configured to operate according to the conventional
method, i.e., the RNC 108 establishes the AAL2 path based on a RRC connection from the UE.
[0054] In one implementation, the Node B 110 may be configured to receive the DCH
setup request message for establishing the AAL2 paths between the RNC 108 and the Node B
110. For the purpose, a processing module 114, of the Node B 110, may be configured for
processing the DCH setup request message. In one implementation, the processing module 114
may be configured to extract and save the binding identities corresponding to the AAL2 paths, as
determined by the RNC 108, in a binding identity list. Consequently, the RNC 108 and the Node
B 110 has the same set of binding identities corresponding to each of the AAL2 paths. Further,
the processing module 114 establishes the AAL2 paths between the RNC 108 and the Node B
110. Subsequently, the Node B 110 sends a DCH setup response message to the RNC 108,
thereby indicating establishment of AAL2 paths between the RNC 108 and the Node B 110.
These AAL2 paths established are in a 'ready to be used' state and may be used for carrying
signaling information associated with the RL. Each of these AAL2 paths established may further
be tagged with a specific DCH_ID which could later be used during call establishment.
[0055] In order to avail different service, such as voice call, video call, Mobile TV,
internet service, and the like, offered by a service provider, the communication device 102 needs
to establish the RL with the Node B 110. For the purpose, the communication device 102, sends
a radio resource connection (RRC) setup request to the RNC 108 for establishing the RL with the
Node B 110 for using services over the communication network 104.
[0056] In one implementation, the RNC 108 may be configured to receive the RRC
connection setup request from the communication device 102. Based upon a category of QoS
associated with the RRC connection setup request, the RNC 108 selects the appropriate AAL2
path which is to be mapped with the communication device 102. In one implementation, the
17
RNC 108 determines the AAL2 path through a conventional algorithm. For mapping the
communication device 102 and the AAL2 path, the RNC 108 sends a NBAP-RL setup request
message, hereinafter referred to as RL setup request message, to the Node B 110. The RL setup
request message, among other fields, contain a binding_id IE field and a transport layer address
(TLA) field. Based upon the binding_ID IE field and the TLA field, the Node B 110 is,
accordingly, configured to map the communication device 102 with the AAL2 path. In one case,
upon receiving the RL setup message with specific binding_id IE field and TLA field, the Node
B 110 establishes the AAL2 paths on internet protocol (IP) architecture. In another case, the
Node B 110, upon receiving the RL setup request message, where the binding_id IE includes a
binding identity corresponding to an AAL2 path and a blank TLA field is configured to map the
communication device 102 with the pre-established AAL2 path. Further, in another case where
the Node B 110 receives the RL setup request message with a blank binding_id IE field and a
blank TLA field, the Node B 110 establishes the RL according to the conventional method as
described earlier. Further, the Node B 110 sends a RL setup response message to the RNC 108,
thereby affirming the mapping of the communication device 102 and the AAL2 path as
determined by the RNC 108. Upon successful exchange of these messages, the RNC 108 sends a
RRC connection setup response message to the communication device 102, thereby indicating
the communication device 102 to establish the radio link with the Node B 110. Further, in case of
a teardown of the AAL2 paths established in the network, the setup procedure for handling the
teardown would be carried out as done in conventional method.
[0057] As seen in the above cases, both, the RNC 108 and the Node B 110 are configured
to generate a binding identity corresponding to an AAL2 path. In order to avoid conflict of
binding identities generated by the RNC 108 and the Node B 110, in one implementation, the
RNC 108 may be configured to use binding identities from 1 to 65534 and the Node B 110 to use
binding identities greater than 65535. In a case where the binding identity is generated by the
Node B 110, the Node B 110 fills in the binding identity in the RL setup response message,
thereby updating the RNC 108 accordingly.
[0058] Establishment of 'ready to be used' AAL2 paths helps in reducing the number of
messages exchanged for establishing the radio link at-least by half, i.e., only two messages are
exchanged for setting up the AAL2 paths for establishing the radio link. Further, even in a case
of establishing an RL with multiple AAL2 paths, only two messages, i.e., the RL setup request
18
and the RL setup response will be exchanged. As a result, the setup time for establishing the
radio link between the UE and the Node B 110 is reduced considerably. Subsequently,
overloading of network resources, such as the Node B 110, during a registration storm, as
described previously, is averted. For the sake of better understanding, the details of the RNC 108
and the Node B 110 are further explained in greater detail with reference of Figure 2(a) and 2(b).
[0059] Figure 2(a) illustrates the components of the RNC 108, and the components of the
Node B 110, according to an embodiment of the present subject matter. In accordance with the
present subject matter, the RNC 108 and the Node B 110 are communicatively coupled to each
other through the various components of the communication network 104 (as shown in Fig.1).
The RNC 108 and the Node B 110 primarily interact with each other using NBAP protocol and
optionally ALCAP protocol.
[0060] The RNC 108 and the Node B 110 include processors 202-1, 202-2, collectively
referred to as processor 202 hereinafter. The processor 202 may be implemented as one or more
microprocessors, microcomputers, microcontrollers, digital signal processors, central processing
units, state machines, logic circuitries, and/or any devices that manipulate signals based on
operational instructions. Among other capabilities, the processor(s) is configured to fetch and
execute computer-readable instructions stored in the memory.
[0061] The functions of the various elements shown in the figure, including any
functional blocks labeled as “processor(s)”, may be provided through the use of dedicated
hardware as well as hardware capable of executing software in association with appropriate
software. When provided by a processor, the functions may be provided by a single dedicated
processor, by a single shared processor, or by a plurality of individual processors, some of which
may be shared. Moreover, explicit use of the term “processor” should not be construed to refer
exclusively to hardware capable of executing software, and may implicitly include, without
limitation, digital signal processor (DSP) hardware, network processor, application specific
integrated circuit (ASIC), field programmable gate array (FPGA), read only memory (ROM) for
storing software, random access memory (RAM), non-volatile storage. Other hardware,
conventional and/or custom, may also be included.
[0062] Also, the RNC 108 and the Node B 110 include I/O interface(s) 204-1, 204-2,
collectively referred to as I/O interfaces 204. The I/O interfaces 204 may include a variety of
19
software and hardware interfaces that allow the RNC 108 and the Node B 110 to interact with the
communication network 104, the UE devices 102 and with each other. Further, the I/O interfaces
204 may enable the RNC 108 and the Node B 110 to communicate with other communication
and computing devices, such as web servers and external repositories. The I/O interfaces 204
may facilitate multiple communications within a wide variety of networks and protocol types,
including wire networks, for example, LAN, cable, etc., and wireless networks, for example,
WLAN, cellular, satellite-based network, etc.
[0063] The RNC 108 and the Node B 110 may include memory 206-1, and 206-2,
respectively, collectively referred to as memory 206. The memory 206-1 and 206-2 may be
coupled to the processor 202-1, and the processor 202-2, respectively. The memory 206 may
include any computer-readable medium known in the art including, for example, volatile
memory (e.g., RAM), and/or non-volatile memory (e.g., EPROM, flash memory, etc.).
[0064] The RNC 108 and the Node B 110 include modules 208-1, 208-2, and data 210-1,
210-2, respectively, collectively referred to as modules 208 and data 210, respectively. The
modules 208 include routines, programs, objects, components, data structures, and the like,
which perform particular tasks or implement particular abstract data types. The modules 208
further include modules that supplement applications on the RNC 108 and the Node B 110, for
example, modules of an operating system.
[0065] Further, the modules 208 can be implemented in hardware, instructions executed
by a processing unit, or by a combination thereof. The processing unit can comprise a computer,
a processor, such as the processor 202, a state machine, a logic array or any other suitable
devices capable of processing instructions. The processing unit can be a general-purpose
processor which executes instructions to cause the general-purpose processor to perform the
required tasks or, the processing unit can be dedicated to perform the required functions.
[0066] In another aspect of the present subject matter, the modules 208 may be machinereadable
instructions (software) which, when executed by a processor/processing unit, perform
any of the described functionalities. The machine-readable instructions may be stored on an
electronic memory device, hard disk, optical disk or other machine-readable storage medium or
non-transitory medium. In one implementation, the machine-readable instructions can be also be
downloaded to the storage medium via a network connection. The data 210 serves, amongst
20
other things, as a repository for storing data that may be fetched, processed, received, or
generated by one or more of the modules 208.
[0067] In an implementation, the modules 208-1 of the RNC 108 include a setup module
112, a network interaction module 212, a user interaction module 214, and other module(s) 216.
In said implementation, the data 210-1 of the RNC 108 includes setup data 218, network
interaction data 220, user interaction data 222, and other data 224. The other module(s) 216 may
include programs or coded instructions that supplement applications and functions, for example,
programs in the operating system of the RNC 108, and the other data 224 comprise data
corresponding to one or more other module(s) 216.
[0068] Similarly, in an implementation, the modules 208-2 of the Node B 110 include an
interaction module 226, a processing module 114, and other module(s) 228. In said
implementation, the data 210-2 of the Node B 110 includes interaction data 230, processing data
232, and other data 234. The other module(s) 228 may include programs or coded instructions
that supplement applications and functions, for example, programs in the operating system of the
Node B 110, and the other data 234 comprise data corresponding to one or more other module(s)
228.
[0069] According to an implementation of the present subject matter, the radio network
controller (RNC) 108 may be configured to send a dedicated channel (DCH) setup request
message to the Node B 110, for establishing a predetermined number of AAL2 paths between the
RNC 108 and the Node B 110. In one implementation, the RNC 108 may be configured to send
the DCH setup request message as a part of an initial setup procedure, between the RNC 108 and
the Node B 110, when the Node B 110 becomes functional after resetting. In another
implementation, after the AAL2 paths have been established during the initial setup procedure,
the RNC 108 may be configured to determine a threshold value for sending another DCH setup
request message. For instance, 50 AAL2 paths are established between the RNC 108 and the
Node B 110 during the initial setup procedure. The RNC 108 may determine a threshold value,
say, 30 for sending another AAL2 paths setup request message. Once 30 AAL2 paths are utilized
within the communication network 104, the RNC 108 sends a DCH setup request message to the
Node B 110 for setting up more DCH.
21
[0070] The AAL2 paths are used for carrying signaling information between the RNC
108 and the Node B 110. For example, AAL2 paths are used for carrying signaling information,
such as transmission power, bit rate, frequency allocated, and the like associated with a radio link
(RL), such as the RL between the communication device 102 and the Node B 110. Further, each
of the AAL2 path has a corresponding binding identity information element (IE), hereinafter
referred to as binding identity, associated with it. In one implementation, binding identities are
used for identifying and mapping the communication device 102 with a particular AAL2 path as
determined by the RNC 108. In one case, the AAL2 paths may be used for carrying user-plane
traffice as will be understood by a person skilled in the art.
[0071] In one implementation, the setup module 112 may be configured to generate the
DCH setup request message. The DCH setup request message contains a plurality of service user
generated reference (SUGR) fields, where each SUGR field contains a binding identity
corresponding to a particular AAL2 path. Further, the setup module 112 may be configured to
generate the SUGR fields. In another implementation, the number of SUGR fields may
determine the number of AAL2 paths that are to be established. For example, for establishing 20
AAL2 paths between the RNC 108 and the Node B 110, the setup module 112 may generate 20
SUGR fields containing binding identities 1 to 20, where each binding identity corresponds to a
particular AAL2 path. In another implementation, the setup module 112 may be configured to
determine a category of quality of service (QoS) associated with the AAL2 paths. In one
implementation, the setup module 112 may be configured to save the self generated binding
identities in the setup data 218. In another implementation, the setup module 112 may store the
DCH setup request message in the setup data 218.
[0072] Further, the network interaction module 212 may be configured for sending the
DCH setup request message to the Node B 110. For the purpose, the network interaction module
212 may be configured to obtain the DCH setup request message stored in the setup data 218.
[0073] In one implementation, the interaction module 226, of the Node B 110, may be
configured for receiving the DCH setup request message. The interaction module 226 may store
the DCH channel setup request in the interaction data 230.
[0074] Further, the processing module 114 may be configured for processing the DCH
setup request message for establishing the AAL2 paths. For the purpose, the processing module
22
114 may obtain the DCH setup request message stored in the interaction data 230. In one
implementation, the processing module 114 is configured to extract the SUGR fields in the DCH
setup request message. The processing module 114, further, stores the binding identities included
in the SUGR fields in a binding identity list. Each of the binding identities corresponds to a
particular AAL2 path as determined by the setup module 112. Further, the processing module
114 may be provisioned to store the binding identity list in the processing data 232.
Subsequently, the RNC 108 and the Node B 110 have same set of binding identities and each
AAL2 path will be identified by the same corresponding binding identity by, both, the RNC 108
and the Node B 110. In one implementation, the processing module 114 may be configured for
establishing the AAL2 path based on the DCH setup request message. Consequently, the
processing module 114 may be configured to generate a DCH setup response message for
indicating the establishment of AAL2 paths between the RNC 108 and the Node B 110. Further,
the processing module 114 may be configured to store the DCH setup response message in the
processing data 232.
[0075] Subsequently, the interaction module 226 may be configured to send the DCH
setup response message to the RNC 108. For the purpose, the interaction module 226 may be
configured to obtain the DCH setup response message stored in the processing data 232. In one
implementation the network interaction module 212 may be configured to receive the DCH setup
response message. Further, the network interaction module 212 may be configured to store the
DCH setup response message in the network interaction data 220.
[0076] In order to avail the different services provided by a service provider, the
communication device 102 needs to establish the RL with the Node B 110 present in the
communication network 104. For the purpose, the communication device 102 sends a radio
resource control (RRC) connection request to the RNC 108. In one implementation, the user
interaction module 214 may be configured for receiving the RRC connection request from the
communication device 102. In one implementation, the user interaction module 214 may be
configured to store the RRC connection setup request in the user interaction data 222.
[0077] In one implementation, based on the subscription plan associated with the
communication device 102, the RNC 108 may be configured to determine whether to use the
existing set of DCH or setup the DCH according to the conventional method. Further, according
23
to the present subject matter, based upon a category of quality of service (QoS) associated with
the RRC connection request, the setup module 112 may be configured to determine a AAL2 path
from amongst a pool of already established AAL2 paths according to a predetermined
conventional algorithm. Further, the setup module 112 may be configured to select the AAL2
path as determined based on the RRC connection request.
[0078] Based on the RRC connection request from the communication device 102, the
setup module 112, further, generates a RL setup request message containing a binding_id
identifying element (IE) field and a transport layer address (TLA) field. In one implementation,
the setup module 112 fills the binding_id IE field of the RL setup request message with the
binding identity corresponding to the AAL2 path selected by the setup module 112. In the said
implementation, the setup module 112 leaves the TLA field of the RL setup message blank, to
indicate to the Node B 110 to map the communication device 102 with the AAL2 path
corresponding to the binding identity specified in the RL setup request message.
[0079] Further, for also establishing the RL according to the conventional method
described earlier, the setup module 112 may be configured to generate the RL setup request
message with blank binding_id IE field and a blank TLA field. In such a case, the Node B 110
may be configured to establish the AAL2 path according to the conventional method as described
earlier. In another implementation, in order to establish the RL according to the IP architecture,
the setup module 112 may be configured to generate the RL setup request message with specific
binding_id IE field and specific TLA field, as would be understood by a person skilled in the art.
Based on the RRC connection request, the RNC 108 and the Node B 110 exchange at least four
messages for establishing the radio link between the communication device 102 and the Node B
110 as per the conventional method. Subsequently, the network interaction module 212 sends the
RL setup request message to the Node B 110.
[0080] In one implementation, at the Node B 110, the interaction module 226 may be
configured to receive the RL setup request. Further, the processing module 114 may be
configured to process the RL setup request message and identify the binding identity stored in
the binding_id IE field of the RL setup message. Subsequently, the processing module 114 maps
the communication device 102 with the AAL2 path corresponding to the binding identity
specified in the RL setup request message and generates a RL setup response message. Further,
24
the interaction module 226 may be configured to send the RL setup response message to the
RNC 108, thereby affirming the mapping of the communication device 102 with the AAL2 path.
Upon successful mapping of the communication device 102, the RNC 108 sends a RRC
connection response to the communication device 102 for establishing the radio link with the
Node B 110, present in the communication network 104.
[0081] Fig. 2(b) illustrates a call-flow diagram indicating a procedure for establishing a
radio link, in accordance with an embodiment of the present subject matter. The various arrow
indicators used in the call-flow diagram depict the transfer of signal/information between the
radio network controller (RNC) 108, the Node B 110, and the communication device 102. In
many cases, multiple network entities besides those shown may lie between the entities,
including transmitting stations, and switching stations, although those have been omitted for
clarity. Similarly, various acknowledgement and confirmation network responses may also be
omitted for clarity. Although the description of Fig. 2(b) has been made in considerable detail
with respect to an UMTS network, it will be understood that establishment of radio link may be
implemented for other networks, albeit with a few variations, as will be understood by a person
skilled in the art.
[0082] In one implementation, the process of establishing the dedicated channels is
initiated with the RNC 108 sending the DCH setup request 252 to the Node B 110. The DCH
setup request 252 contains a plurality of service user generated reference (SUGR) fields, where
each SUGR field includes a binding identity corresponding to an AAL2 path, as determined by
the RNC 108. In one implementation, the number of SUGR fields indicates the number of AAL2
paths that are to be established between the RNC 108 and the Node B 110. In one
implementation, the RNC 108 sends the DCH setup request 252 as a part of an initial setup
procedure, between the RNC 108 and the Node B 110, when the Node B 110 becomes functional
after resetting. In another implementation, after the AAL2 paths have been established during the
initial setup procedure, the RNC 108 may determine a threshold value for sending another DCH
setup request 252. For instance, 100 AAL2 paths are established between the RNC 108 and the
Node B 110 during the initial setup procedure. The RNC 108 may determine a threshold value,
say, 75 for sending another DCH setup request 252. As soon as, 75 AAL2 paths are utilized
within the communication network 104, the RNC 108 sends another DCH setup request 252 to
the Node B 110 for setting up more AAL2 paths.
25
[0083] On receiving the DCH setup request 252, the Node B 110 extracts the SUGR
fields and stores the binding identities corresponding to the AAL2 paths in a binding identity list.
Consequently, the RNC 108 and the Node B 110 have the same set of binding identities
corresponding to the AAL2 paths. Further, the Node B 110 sends the DCH setup response 254 to
the RNC 108 thereby indicating the establishment of AAL2 paths between the RNC 108 and the
Node B 110.
[0084] In order to establish the radio link with the Node B 110, the communication
device 102 sends the RRC connection request 256 to the RNC 108. Further, the RNC 108
determines the category of quality of service associated with the RRC connection request 256
and selects the AAL2 path, which is to be mapped with the communication device 102, where
the AAL2 path is determined based on a conventional algorithm. Upon selecting the AAL2 path,
the RNC 108 fills the binding identity corresponding to the AAL2 path in the binding_id IE field
of the RL setup request 258. The RNC 108 leaves the TLA field of the RL setup request 258
blank for indicating the Node B 110 to map the communication device 102 with the AAL2 path
corresponding to the binding identity specified in the RL setup request 258. Further the RNC
108, send the RL setup request 258 to the Node B 110.
[0085] On receiving the RL setup request 258, the Node B 110 maps the communication
device 102 with the AAL2 path corresponding to the binding identity specified in the binding_id
IE field of the RL setup request 258. Further, the Node B 110 sends the RL setup response 260 to
the RNC 108 indicating the mapping of the communication device 102 and the AAL2 path.
[0086] On receiving the RL setup response 260, the RNC 108 sends the RRC connection
response to the communication device 102 for establishing the radio link with the Node B 110.
[0087] As observed the RNC 108 and the Node B 110 exchange only two messages for
mapping the communication device 102 with the AAL2 path based on the RRC connection
request 262, thereby reducing the setup time required for establishing the radio link between the
communication device 102 and the Node B 110. Consequently, overloading of the system
resources is averted and better utilization of network bandwidth is achieved as the number of
messages exchanged for setting up the radio link are reduced.
[0088] Typically, establishment of the AAL2 path is performed through a transport
network protocol, for example, ALCAP protocol, leading to exchange of at least two ALCAP
26
message-exchanges for establishing each of the AAL2 path based on the RRC connection
request. However, establishment of DCH through ALCAP protocol might overload the system
resources, for instance, when network resources, such as the Node B is upgraded. Thus,
establishing the AAL2 paths through a radio network protocol, such as the NBAP protocol, helps
in avoiding excessive transport network control protocol initial setup messages.
[0089] Fig. 3 illustrates an exemplary method 300 for establishing a radio link in
universal mobile telecommunication network, according to an embodiment of the present subject
matter. The order in which the method 300 is described is not intended to be construed as a
limitation, and any number of the described method blocks can be combined in any order to
implement the method 300, or an alternative method. Additionally, individual blocks may be
deleted from the method without departing from the spirit and scope of the subject matter
described herein. Furthermore, the method can be implemented in any suitable hardware,
software, firmware, or combination thereof.
[0090] The method(s) may be described in the general context of computer executable
instructions. Generally, computer executable instructions can include routines, programs, objects,
components, data structures, procedures, modules, functions, etc., that perform particular
functions or implement particular abstract data types. The method may also be practiced in a
distributed computing environment where functions are performed by remote processing devices
that are linked through a communications network. In a distributed computing environment,
computer executable instructions may be located in both local and remote computer storage
media, including memory storage devices.
[0091] A person skilled in the art will readily recognize that steps of the method can be
performed by programmed computers. Herein, some embodiments are also intended to cover
program storage devices, for example, digital data storage media, which are machine or
computer readable and encode machine-executable or computer-executable programs of
instructions, wherein said instructions perform some or all of the steps of the described method.
The program storage devices may be, for example, digital memories, magnetic storage media,
such as a magnetic disks and magnetic tapes, hard drives, or optically readable digital data
storage media. The embodiments are also intended to cover both communication network and
communication devices configured to perform said steps of the exemplary method.
27
[0092] At block 302, a dedicated channel (DCH) setup request message containing a
plurality of service user generated reference (SUGR) fields is generated. In one implementation,
a radio network controller (RNC), such as the RNC 108 may be configured for generating the
DCH setup request message containing the SUGR fields for establishing the AAL2 paths
between the RNC and a Node B. In one implementation, the RNC may be configured for
generating the SUGR fields of the DCH setup request, where each SUGR field includes a
binding identity corresponding to an AAL2 path. In the said implementation, the number of
SUGR fields corresponds to the number of AAL2 paths that are to be established between the
RNC and a Node B. For example, for establishing 50 AAL2 paths, the RNC may send a DCH
setup request comprising of 50 SUGR fields, where the SUGR fields contains binding identities
1 to 50. Further, each of the binding identities, 1 to 50, correspond to a particular AAL2 paths
which is to be established. In one implementation, the AAL2 path may be used for carrying
signaling information, such as transmission power, bit rate, handover signaling information and
the like associated with a radio link (RL) established between a communication device, such as
the communication device 102 and the Node B 110, meant for either the Node B 110 or the RNC
108.
[0093] At block 304, the DCH setup request message is sent. In one implementation, the
RNC sends the DCH setup request to the Node B for establishing the AAL2 paths. Typically, the
RNC 108 manages the Node B 110 through a signaling protocol, such as the NBAP protocol,
over an interface, such as the IuB interface as described previously. In one implementation, the
RNC 108 may be configured to send the DCH setup request using the NBAP protocol. In one
implementation, the DCH setup request message will typically look like an NBAP message
consisting of ‘n’ ALCAP ERQs.
[0094] At block 306, a DCH setup response is received. In one implementation, the RNC
may be configured to receive the DCH setup response from the Node B. The DCH setup
response affirms the establishment of the AAL2 paths between the RNC 108 and the Node B
110.
[0095] At block 308, a radio link (RL) setup request is sent. Typically, in order to avail
the different services offered by a service provider, the communication device sends a radio
resource connection (RRC) connection request, for establishing the RL with the Node B, to the
28
RNC. In one implementation, based on a category of quality of service associated with the RRC
connection request, the RNC selects the AAL2 path which is to be mapped with the
communication device. The selection of AAL2 path is done through a predetermined algorithm.
Further, the RNC 108 sends the RL setup request to the Node B 110. The RL setup request
contains the binding identity corresponding to the AAL2 path, as determined by the RNC, which
is to be mapped with the communication device. In another implementation, the RNC 108 may
send the RL setup request message without the binding identity, thereby indicating the Node B
110 to establish the radio link according to the conventional method described earlier. Upon
receiving the RL setup request, the Node B 110 maps the AAL2 path corresponding to the
binding identity specified in the RL setup request with the communication device 102.
[0096] At block 310, a RL setup response is received. In one implementation, the Node B
sends the RL setup response to the RNC indicating the mapping of the AAL2 path with the
communication device. Subsequently, the RNC 108 sends a RRC connection response to the
communication device 102 for establishing the radio link with the Node B 110.
[0097] As observed, only two messages are exchanged between the RNC 108 and the
Node B 110 for establishing the radio link, irrespective of the number of AAL2 paths that are
required to be setup, thereby reducing the setup time required for establishing the radio link.
Consequently, overloading of network resources, such as the Node B, due to a flurry of RRC
connection requests may be averted, thereby improving the availability of network services to a
user of the communication device.
[0098] Fig. 4 illustrates an exemplary method 400 for establishing a radio link in
universal mobile telecommunication network, according to an embodiment of the present subject
matter. The order in which the method 400 is described is not intended to be construed as a
limitation, and any number of the described method blocks can be combined in any order to
implement the method 400, or an alternative method. Additionally, individual blocks may be
deleted from the method without departing from the spirit and scope of the subject matter
described herein. Furthermore, the method can be implemented in any suitable hardware,
software, firmware, or combination thereof.
[0099] The method(s) may be described in the general context of computer executable
instructions. Generally, computer executable instructions can include routines, programs, objects,
29
components, data structures, procedures, modules, functions, etc., that perform particular
functions or implement particular abstract data types. The method may also be practiced in a
distributed computing environment where functions are performed by remote processing devices
that are linked through a communications network. In a distributed computing environment,
computer executable instructions may be located in both local and remote computer storage
media, including memory storage devices.
[00100] A person skilled in the art will readily recognize that steps of the method can be
performed by programmed computers. Herein, some embodiments are also intended to cover
program storage devices, for example, digital data storage media, which are machine or
computer readable and encode machine-executable or computer-executable programs of
instructions, wherein said instructions perform some or all of the steps of the described method.
The program storage devices may be, for example, digital memories, magnetic storage media,
such as a magnetic disks and magnetic tapes, hard drives, or optically readable digital data
storage media. The embodiments are also intended to cover both communication network and
communication devices configured to perform said steps of the exemplary method.
[00101] At block 402, a dedicated channel (DCH) setup request message containing a
plurality of service user generated reference (SUGR) fields is received. In one implementation, a
Node B, such as the Node B 110, may be configured for receiving the DCH setup request
message from a radio network controller (RNC). Each of the SUGR field includes a binding
identity corresponding to an AAL2 path that is to be established between the Node B 110 and the
RNC 108. In one implementation, the AAL2 path may be used for carrying signaling
information, such as transmission power, bit rate, handover signaling information, and the like
associated with a radio link (RL) established between a communication device, such as the
communication device 102, and the Node B 110. For example, the interaction module 226 of the
Node B 110 receives the DCH setup request message from the RNC 108.
[00102] At block 404, the SUGR fields are extracted from the DCH setup request
message. In one implementation, The Node B may be configured to extract the SUGR fields,
where each SUGR field contains a binding identity corresponding to an AAL2 path which is to
be established. In one implementation, the number of SUGR fields correspond to the number of
30
AAL2 paths that are to be established. For example, the processing module 114 of the Node B
110 is configured to extract the SUGR fields.
[00103] At block 406, the binding identities are stored in a binding identity list. In one
implementation, the Node B may be configured to store the binding identities in the binding
identity list. The binding identity list enlists the binding identities, where each binding identity
corresponds to an AAL2 path DCH. For example, the processing module 114 stores the binding
identity list in the processing data 232.
[00104] At block 408, the AAL2 paths are established based on the DCH path setup
request message. In one implementation, the Node B establishes the AAL2 paths. In one
implementation, the number of AAL2 paths to be established correspond to the number of SUGR
fields in the DCH setup request message. For example, the processing module 114 establishes
the AAL2 paths based on the DCH setup request message.
[00105] At block 410, a DCH setup response message is sent. In one implementation, the
Node B may be configured to send the DCH setup response message to the RNC, thereby
indicating the establishment of AAL2 paths where each DCH corresponds to a binding identity.
In one implementation, the DCH setup response message essentially looks like a conventional
NBAP message consisting of 'n' ALCAP ECF's.
[00106] At block 412, a radio link (RL) setup request message is received. In one
implementation, the Node B may be configured to receive the RL setup request message from
the RNC. In one implementation, the RL setup request message includes the binding identity of
the DCH which is to be mapped with the communication device. Additionally, the Node B is also
configured to establish the DCH link as per the conventional method described earlier upon
receiving the RL setup message without the binding identity.
[00107] At block 414, a RL setup response message is sent. In one implementation, the
Node B may be configured to send the RL setup response message upon completion of mapping
of the communication device with the DCH based on the RL setup request message.
[00108] As observed, establishing AAL2 paths in advanced helps in reducing the setup
time for establishing the RL between the UE and the Node B, as only two messages are
exchanged for setting up the AAL2 path for establishing the radio link. Further, even in a case of
establishing an RL with multiple AAL2 paths, only two messages, i.e., the RL setup request and
31
the RL setup response will be exchanged. As a result, the setup time for establishing the RL
between the UE and the Node B is reduced considerably. Subsequently, overloading of network
resources, such as the Node B, during a registration storm, as described previously, is averted.
[00109] Although embodiments for methods and systems for establishing a radio link in
universal mobile telecommunication system have been described in a language specific to
structural features and/or methods, it is to be understood that the invention is not necessarily
limited to the specific features or methods described. Rather, the specific features and methods
are disclosed as exemplary embodiments for establishing a radio link in universal mobile
telecommunication system.
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I/We claim:
1. A method for establishing a radio link in universal mobile telecommunication network, the
method comprising:
generating a dedicated channel setup request message for establishing a plurality of
asynchronous transfer mode (ATM) adaption layer 2 (AAL2) paths, wherein the dedicated
channel setup request message comprises a plurality of service user generated (SUGR)
fields, wherein each SUGR field includes a binding identity, and wherein each binding
identity corresponds to an AAL2 path;
sending the dedicated channel setup request message to a Node B; and
receiving a dedicated channel setup response message from the Node B.
2. The method as claimed in claim 1, wherein a number of the SUGR fields is equal to a
number of AAL2 paths that are to be established.
3. The method as claimed in claims 1-2, wherein each AAL2 path has a particular level of
quality of service.
4. The method as claimed in claims 1-3, wherein the method further comprises:
identifying an AAL2 path based on a level of quality of service associated with a
radio resource connection request; and
sending a radio link setup request message, wherein the radio link setup message
includes a blank binding_id IE field.
5. The method as claimed in claim 1-3, wherein the method further comprises:
selecting an AAL2 path from the plurality of AAL2 paths based on a level of quality
of service associated with a radio resource connection request; and
sending a radio link setup request message, wherein a binding_id IE field of the radio
link setup message includes a binding identity corresponding to the AAL2 path.
6. A method for processing a dedicated channel setup request message in a Node B, the
method comprising;
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receiving a dedicated channel setup request message from a radio network controller,
wherein the dedicated channel setup request message comprises a plurality of SUGR fields,
and wherein each SUGR field includes a binding identity corresponding to an AAL2 path;
extracting the plurality of SUGR fields from the dedicated channel setup request
message;
establishing a plurality of AAL2 paths based on the SUGR fields; and
sending a dedicated channel setup response message to the radio network controller.
7. The method as claimed in claim 6, wherein the method further comprises:
receiving a radio link setup request message, wherein a binding_id IE field of the
radio link setup message includes a binding identity corresponding to the AAL2 path;
mapping the AAL2 path specified in the radio link setup request message with a
communication device; and
sending a radio link setup response message.
8. The method as claimed in claim 6, wherein the binding identities are stored in a binding
identity list.
9. A radio network controller (108) comprising:
a processor (202); and
a setup module (112) coupled to the processor (202), the setup module (112)
configured to generate a dedicated channel setup request message for establishing a
plurality of asynchronous transfer mode (ATM) adaption layer 2 (AAL2) paths, wherein
the dedicated channel setup request message comprises a plurality of service user generated
(SUGR) fields, wherein each SUGR field includes a binding identity, and wherein each
binding identity corresponds to an AAL2 path.
10. The radio network controller (108) as claimed in claim 9, wherein the setup module (112)
is further configured to determine a category of quality of service associated with each
AAL2 path.
11. The radio network controller (108) as claimed in claim 9, wherein the setup module (112)
is further configured to generate a radio link setup request message, wherein the radio link
setup request message includes a blank binding_id IE field.
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12. The radio network controller (108) as claimed in claim 9, wherein the setup module (112)
is further configured to generate the radio link setup request message, wherein a binding_id
IE field in the radio link setup request message includes a binding identity corresponding to
a AAL2 path.
13. The radio network controller (108) as claimed in claim 9 further comprising a network
interaction module (212) coupled to the processor (202), the network interaction module
(212) configured to
transmit the dedicated channel setup request message to a Node B (110) for
establishing a plurality of AAL2 paths; and
receive a dedicated channel setup response message from the Node B (110).
14. A Node B (110) comprising:
a processor (202); and
a processing module (114) coupled to the processor (202), the processing module
(114) configured to:
extract a plurality of SUGR fields of a dedicated channel setup request message,
wherein each SUGR field includes a binding identity corresponding to a AAL2 path;
and
establish a plurality of AAL2 paths based on the dedicated channel setup request
message.
15. The Node B (110) as claimed in claim 14, wherein the processing module (114) is further
configured to store the binding identities in a binding identity list.
16. The Node B (110) as claimed in claim 14, wherein the processing module (114) is further
configured to generate a dedicated channel setup response message.
17. The Node B (110) as claimed in claim 14 further comprising an interaction module (226)
coupled to the processor (202), the interaction module (226) configured to transmit the
dedicated channel setup response message to a radio network controller (108).
18. The Node B (110) as claimed in claim 14, wherein the processing module (114) is further
configured to:
map a communication device (102) with a binding identity based on receipt of a
RL setup request message from a radio network controller (108), wherein the RL setup
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request message includes the binding identity, and wherein the binding identity
corresponds to the AAL2 path; and
send a RL setup response message.
19. A computer-readable medium having embodied thereon a computer program for executing
a method of establishing a radio link in a communication network, the method comprising:
generating a dedicated channel setup request message for establishing a plurality of
asynchronous transfer mode (ATM) adaption layer 2 (AAL2) paths, wherein the dedicated
channel setup request message comprises a plurality of service user generated (SUGR)
fields, wherein each SUGR field includes a binding identity, and wherein each binding
identity corresponds to an AAL2 path;
sending the dedicated channel setup request message to a Node B; and
receiving a dedicated channel setup response message from the Node B.
20. A computer-readable medium having embodied thereon a computer program for executing
a method of processing a dedicated channel setup request message in a Node B, the method
comprising:
receiving a dedicated channel setup request message from an RNC, wherein the
dedicated channel setup request message comprises a plurality of SUGR fields, and
wherein each SUGR field includes a binding identity corresponding to a AAL2 path;
extracting one or more of the plurality of SUGR fields from the dedicated channel
setup request message;
establishing the plurality of AAL2 paths based on the SUGR fields; and
sending a dedicated channel setup response message to the RNC.
Date 28 November 2012