1. Field of the Invention
The invention relates to mobile telecommunication systems. In particular, the invention relates to a novel method, system and network nodes for transferring already started process information to a target radio access network node during a relocation procedure.
2. Description of the Related Art
There are a number of different standards known which govern the communication between mobile stations and the base stations as well as with other network elements. One example of a currently known standard is the Global System for Mobile communications (GSM) standard. Currently, work is being carried out on so-called third generation standards. These third generation standards are generated by a so called 3rd Generation Partnership Project (3GPP) and they are defining so called 3GPP system comprising UMTS Terrestrial Radio Access Network (UTRAN), GSM/EDGE Radio Access Network (GERAN), packet and circuit switched core network domains etc.
In the current specifications of the third generation mobile networks (referred to as UMTS), the system utilizes the same well-known architecture that has been used by all main second-generation systems. A block diagram of the system architecture of current UMTS network is presented in
The UTRAN architecture consists of several radio network subsystems (RNS). The RNS is further divided into the Radio Network Controller (RNC) and several base stations (BS, also referred to as node B in the 3d Generation Partnership Project (3GPP) specifications).
In this architecture there are several different connections between the network elements. The Iu interface connects the CN to the UTRAN. The Iur interface enables the exchange of signaling information, as well as the establishment of user plane connections, between two RNCs. The signaling protocol across the Iur interface is called the Radio Network Subsystem Application Part (RNSAP). The RNSAP is terminated at both ends of the Iur interface by an RNC. The Radio Access Network Application Part (RANAP) is a radio access network signaling protocol that consists of mechanisms, which handle procedures between the core network and radio access network. The Iur interface RNSAP signaling is described in more detail e.g. in the 3GPP TS 25.423 V5.6.0 (2003-06). The Iu interface RANAP signaling is described in more detail e.g. in the 3GPP TS 25.413 V5.5.0 (2003-06). In general, the Iu interface is specified in the 25.41Ă—series of the 3GPP UMTS Technical Specifications. Correspondingly, the Iur interface is specified in the 25.42x series of the 3GPP UMTS Technical Specifications.
Furthermore, in Release 5 GERAN Iu mode case, a GERAN network may be connected to a UTRAN network via the Iur-g interface. A source RNC of a UTRAN and a target Base Station Controller (BSC) of a GERAN, a serving BSC of a GERAN and a target RNC of a UTRAN, and a serving BSC of a GERAN and a target BSC of a GERAN use Iur-g interface e.g. for signaling purposes. The GERAN is described e.g. in the 3GPP TS 43.051 V5.9.0 (2003-04) and the Iur-g interface e.g. in the 3GPP TS 25.423 V5.6.0 (2003-06).
A relocation of a Serving Radio Network Subsystem) SRNS is a UMTS functionality used to relocate the Serving RNS role from one RNS to another RNS. This UMTS functionality is realized by several elementary procedures executed in several interfaces and by several protocols and it may involve a change in the radio resources used between UTRAN and UE. This functionality allows moving the Serving RNS functionality from one RNC to another RNC, e.g. closer to where the UE has moved during the communication. The Serving RNS Relocation procedure may be applied when active cell management functionality has created a suitable situation for it.
The term serving RNS refers to a role an RNS can take with respect to a specific connection between an LE and UTRAN. There is one serving RNS for each UE that has a connection to UTRAN. The serving RNS is in charge of the radio connection between a LE and the UTRAN. The serving RNS terminates the Iu for this LE. Furthermore, Serving RNC (SRNC) is the RNC belonging to a SRNS.
It is also possible to relocate the serving RNS role from (a) one RNS within UMTS to another relocation target external to UMTS or (b) functionality equivalent to the serving RNS role from another relocation source external to UMTS to another RNS.
A core network (CN) can initiate in a radio access network (RAN) via Iu signaling the two following processes that will continue until the CN stops them:
The purpose of the Location Reporting Control procedure is to allow the CN to request information on the location of a given UE. The procedure uses connection oriented signaling. Correspondingly, the purpose of the CN Invoke Trace procedure is to inform the RNC that it should begin producing a trace record of a type indicated by the CN and related to the UE. The procedure uses connection oriented signaling.
Therefore, according to the 3GPP UMTS Technical Specifications the order to perform location reporting at change of Service Area is lost in UTRAN at a successful Relocation of SRNS. If the location reporting at change of Service Area shall continue also after the relocation has been performed, the Location Reporting Control procedure shall thus be reinitiated from the CN towards the future SRNC after the Relocation Resource Allocation procedure has been executed successfully.
Correspondingly, the order to perform tracing is lost in UTRAN at successful Relocation of SRNS. If the tracing shall continue also after the relocation has been performed, the CN Invoke Trace procedure shall thus be re-initiated from the CN towards the future SRNC after the Relocation Resource Allocation procedure has been executed successfully.
The first aspect of the invention discloses a method for transferring a existing process information during a relocation procedure in a mobile telecommunication network comprising a core network node, a source radio access network node and a target radio access network node, wherein the method comprises the steps of starting a first process by sending an RANAP CN Invoke Trace message from said core network node to said source radio access network node; starting a second process by sending an RANAP Location Reporting Control message from said core network node to said source radio access network node; including a context of said first and second processes in at least one of a standard RANAP and RNSAP message in one of said core network node and said source radio access network node; sending said at least one of a standard RANAP and RNSAP message from one of said core network node and said source radio access network node to said target radio access network node; and handling said context in said target radio access network node as it would have been received in an RANAP CN Invoke Trace and an RANAP Location Reporting Control message.
The second aspect of the invention discloses a source radio access network node of a mobile communication network comprising receiving means for receiving an RANAP CN Invoke Trace and an RANAP Location Reporting Control message from a core network node, the messages starting a first and a second process; including means for including a context of said first and second processes in at least one of a standard RANAP and RNPAP message; and sending means for sending said at least one of a standard RANAP and RNSAP message to one of said core network node and a target radio access network node.
The third aspect of the invention discloses a target radio access network node of a mobile communication network comprising receiving means for receiving from one of a source radio access network node and a core network node a standard RANAP or RNSAP message comprising a context relating to an RANAP CN Invoke Trace message and an RANAP Location Reporting Control message; and handling means for handling said context as it would have received said context from said core network node included in an RANAP CN Invoke Trace and an RANAP Location Reporting Control message.
The fourth aspect of the invention discloses a core network node of a mobile communication network comprising means for setting a flag in an RANAP CN Invoke Trace message authorizing a source radio access network node to relocate a first process relating to said RANAP CN Invoke Trace message when relocation occurs; means for setting a flag in an RANAP Location Control Reporting message authorizing said source radio access network node to relocate a second process relating to said RANAP Location Control Reporting message when relocation occurs; and means for sending an RANAP CN Invoke Trace message and an RANAP Location Reporting Control message to said source radio access network node.
The fifth aspect of the invention discloses a core network node of a mobile communication network comprising means for sending an RANAP CN Invoke Trace message relating to a first process to a source radio access network node; means for sending an RANAP Location Reporting Control message relating to a second process to said source radio access network node; means for including a context of said first and second processes in an RANAP Relocation Request message; and means for sending said RANAP Relocation Request message comprising said context to a target radio access node.
The sixth aspect of the invention discloses a system for transferring existing process information during a relocation procedure in a mobile telecommunication network comprising a core network node, a source radio access network node and a target radio access network node, wherein the system further comprises receiving means for receiving an RANAP CN Invoke Trace and an RANAP Location Reporting Control message from a core network node, the messages starting a first and a second process; including means for including a context of said first and second processes in at least one of a standard RANAP and RNSAP message; sending means for sending said at least one of a standard RANAP and RNSAP message to one of said core network node and a target radio access network node; and handling means for handling said context as it would have received said context from said core network node included in an RANAP CN Invoke Trace and an RANAP Location Reporting Control message.
The invention has several advantages over the prior-art solutions. Considering the high frequency of relocations, the invention improves the continuity of those processes and saves Iu signaling by avoiding reinitialization of those processes after relocation.
With the use of the invention the core network has the confirmation that the target RNC has successfully started trace after relocation. This is accomplished by using the flag. At present, the core network cannot be sure e.g. with the existing Release 99/4/5 RANAP message that the RNC has really started trace.
The accompanying drawings, which are included to provide a further understanding of the invention and constitute a part of this specification, illustrate embodiments of the invention and together with the description help to explain the principles of the invention. In the drawings:
Reference will now be made in detail to the embodiments of the invention, examples of which are illustrated in the accompanying drawings.
The core network node CN sends two RANAP messages (30 and 31) to the source radio network controller SRNC:
Messages 32-35 relate to normal relocation messaging between the SRNC, TRNC and CN.
In this embodiment, the SRNC includes the context of those RANAP ongoing processes in the RNSAP Relocation Commit message (36) via the included RANAP Relocation Information message sent to the TRNC. The TRNC will handle the context in the same way as it would have been received included in one RANAP Location Reporting Control message or one RANAP CN Invoke Trace message.
If the CN is involved in the relocation, it may need to allow such transfer and be aware of its outcome. Therefore, the CN can authorize the SRNC using a flag in the initial RANAP Location Reporting Control and RANAP CN Invoke Trace messages (30 and 31) to relocate those processes when relocation occurs. Furthermore, the CN may need to know that the processes have been successfully transferred via the Iur interface to the TRNC. For achieving this, the TRNC may inform the CN using a flag in the RANAP Relocation Detect/Complete messages (37) of the outcome of the.
If the flag is not present, the CN shall reinitiate the processes by the RANAP Location Reporting Control message and RANAP CN Invoke Trace message.
The signaling described in
The core network node CN sends two RANAP messages (40 and 41) to the source radio network controller SRNC:
Message 42 relates to normal relocation messaging between the SRNC and CN.
In this embodiment, the CN includes the context of the ongoing RANAP processes in the RANAP Relocation Request message (43) sent to the TRNC. The TRNC will handle the context in the same way, as it would have been received included in one RANAP Location Reporting Control message or one RANAP CN Invoke Trace message.
Furthermore, the CN may need to know that the processes have been successfully transferred via the Iur interface to the TRNC. For achieving this, the TRNC may inform the CN using a flag in the RANAP Relocation Request Acknowledge message (44) of the outcome of the transfer.
If the flag is not present, the CN shall reinitiate the processes by RANAP Location Reporting Control message and RANAP CN Invoke Trace message.
The signaling described in
The core network node CN sends two RANAP messages (50 and 51) to the source radio network controller SRNC:
In this embodiment, the SRNC includes the context of the RANAP ongoing processes in the Source RNC to Target RNC transparent container included in the RANAP Relocation Required message (50). The CN will include the Source RNC to Target RNC transparent container included in the RANAP Relocation Required message into the RANAP Relocation Request message (51) sent to the TRNC.
The TRNC will handle the context in the same way, as it would have been received included in one RANAP Location Reporting Control message or one RANAP CN Invoke Trace message.
The CN may need to allow such transfer of processes and to know that the processes have been successfully transferred via the Iur interface to the TRNC. Therefore, the CN can authorize the SRNC using a flag in the initial RANAP Location Reporting Control and RANAP CN Invoke Trace messages (50 and 51) to relocate those processes when relocation occurs. Furthermore, the TRNC may inform the CN using a flag in the RANAP Relocation Acknowledge message (54) of the outcome of the transfer.
If the flag is not present, the CN shall reinitiate the processes by the RANAP Location Reporting Control message and RANAP CN Invoke Trace message.
The signaling described in
The three different embodiments above (
In the 3GPP release 5, the Gn interface between two SGSNs does not support the reinitialization of the aforementioned ongoing RANAP processes.
The solution disclosed in the first embodiment described with
The solution disclosed in the second embodiment with
The solution disclosed in the third embodiment with
In the 3GPP release 5, the MAP (Mobile Application Part) interface between two MSCs already supports the reinitialization of the aforementioned ongoing RANAP processes.
The solution disclosed in the first embodiment described with
The solution disclosed in the second embodiment with
The solution disclosed in the third embodiment with
In
The target radio access network node TRNC comprises receiving means RM2 for receiving from the source radio access network node SRNC an RNSAP Relocation Commit message comprising an RANAP Relocation Information message comprising the context relating to the RANAP CN Invoke Trace and RANAP Location Reporting Control messages and handling means HM1 for handling the context as it would have been received from the core network node CN included in an RANAP CN Invoke Trace and an RANAP Location Reporting Control message.
The target radio access network node TRNC further comprises setting means SET1 for setting a flag in at least one of an RANAP Relocation Detect and RANAP Relocation Complete message indicating whether the context was successfully transferred to the target radio access network node TRNC and sending means SM2 for sending the at least one of an RANAP Relocation Detect and RANAP Relocation Complete message to the core network node CN.
The core network node CN comprises setting means SET2 for setting a flag in an RANAP CN Invoke Trace message authorizing the source radio access network node SRNC to relocate a first process relating to the RANAP CN Invoke Trace message when relocation occurs, setting means SET2 for setting a flag in an RANAP Location Control Reporting message authorizing the source radio access network node SRNC to relocate a second process relating to the RANAP Location Control Reporting message when relocation occurs and sending means SM3 for sending the RANAP CN Invoke Trace message and RANAP Location Reporting Control message to the source radio access network node SRNC.
The core network node CN further comprises receiving means RM4 for receiving from the target radio access network node TRNC at least one of an RANAP Relocation Detect and RANAP Relocation Complete message comprising a flag indicating whether the first and second processes were successfully transferred to the target radio access network node TRNC and reinitiating means RE1 for reinitiating the first and second processes if the flag indicated an unsuccessful transfer of the first and second processes.
The source radio access network node SRNC comprises receiving means RM11 for receiving an RANAP CN Invoke Trace and an RANAP Location Reporting Control message from a core network node, including means IM11 for including a context of the first and second processes in at least one of a standard RANAP and RNSAP message and sending means SM1 for sending the at least one of a standard RANAP and RNSAP message to one of the core network node CN and the target radio access network node TRNC. Including means IM11 are arranged to include the context of the first and second processes node in the Source RNC to Target RNC transparent container included in an RANAP Relocation Required message and sending means SM11 are arranged to send the RANAP Relocation Required message to the core network node CN.
The target radio access network node TRNC comprises receiving means RM21 for receiving from the core network node CN an RANAP Relocation Request message comprising the context relating to the RANAP CN Invoke Trace and RANAP Location Reporting Control messages and handling means HM11 for handling the context as it would have received the context from the core network node CN included in an RANAP CN Invoke Trace and an RANAP Location Reporting Control message.
The target radio access network node TRNC further comprises setting means SET11 for setting a flag in an RANAP Relocation Request Acknowledge message indicating whether the context was successfully transferred to the target radio access network node TRNC and sending means SM12 for sending the RANAP Relocation Request Acknowledge message to the core network node CN.
The core network node CN comprises setting means SET21 for setting a flag in an RANAP CN Invoke Trace message authorizing the source radio access network node SRNC to relocate a first process relating to the RANAP CN Invoke Trace message when relocation occurs, setting means SET21 for setting a flag in an RANAP Location Control Reporting message authorizing the source radio access network node SRNC to relocate a second process relating to the RANAP Location Control Reporting message when relocation occurs and sending means SM31 for sending the RANAP CN Invoke Trace message and RANAP Location Reporting Control message to the source radio access network node SRNC.
The core network node CN further comprises receiving means RM31 for receiving from the source radio access network node an RANAP Relocation Required message comprising the Source RNC to Target RNC transparent container including a context relating to the first and second processes and sending means SM31 arranged to send an RANAP Relocation Request message comprising the context to the target radio access network node TRNC.
The core network node CN further comprises receiving means RM41 for receiving from the target radio access network node TRNC an RANAP Relocation Request Acknowledge message comprising a flag indicating whether the first and second processes were successfully transferred to the target radio access network node TRNC and reinitiating means RE11 for reinitiating the first and second processes if the flag indicated an unsuccessful transfer of the first and second processes.
The target radio access network node TRNC comprises receiving means RM22 for receiving from the core network node CN an RANAP Relocation Request message comprising a context relating to an RANAP CN Invoke Trace message and an RANAP Location Reporting Control message and handling means HM12 for handling the context as it would have received the context from the core network node CN included in an RANAP CN Invoke Trace and an RANAP Location Reporting Control message.
The target radio access network node TRNC further comprises setting means SET12 for setting a flag in an RANAP Relocation Request Acknowledge message indicating whether the context was successfully transferred to the target radio access network node TRNC and sending means SM22 for sending the RANAP Relocation Request Acknowledge message to the core network node CN.
The core network node CN comprises sending means SM42 for sending an RANAP CN Invoke Trace message relating to a first process to the source radio access network node SRNC, sending means SM42 for sending an RANAP Location Reporting Control message relating to a second process to the source radio access network node SRNC, including means IM22 for including a context of the first and second processes in an RANAP Relocation Request message and sending means SM52 for sending the RANAP Relocation Request message comprising the context to the target radio access node TRNC.
The core network node CN further comprises receiving means RM52 for receiving from the target radio access network node TRNC an RANAP Relocation Request Acknowledge message comprising a flag indicating whether the first and second processes were successfully transferred from the source radio access network node SRNC to the target radio access network node TRNC and reinitiating means RE22 for reinitiating the first and second processes if the flag indicated an unsuccessful transfer of the first and second processes.
The aforementioned means may be implemented with at least one of software and hardware components in a manner known to a man skilled in the art, and therefore they are not described in more detail.
It is obvious to a person skilled in the art that with the advancement of technology, the basic idea of the invention may be implemented in various ways. The invention and its embodiments are thus not limited to the examples described above, instead they may vary within the scope of the claims.
Number | Date | Country | Kind |
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20031457 | Oct 2003 | FI | national |