Cisco Cisco Packet Data Interworking Function (PDIF) Notas De La Versión
SGSN Changes in Release 15.0
▀ SGSN Enhancements for September 30, 2013
▄ Cisco ASR 5x00 Release Change Reference
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The packet-based services that are active on the end-user device at this time are handed over and
continue to run in a system with circuit-switched voice support but with lower data speeds.
OR
The packet-based services that are active on the end-user device at this time are suspended until the
voice call is terminated and the terminal switches back to LTE again and the packet services are
resumed.
resumed.
Voice calls received by the mobile user: If there is an incoming voice call to an end-user that is currently
attached to the LTE system, the MSC-Server requests a paging in the LTE system for the specific user. This is
done through the SGs interface between the MSC Server and the MME. The terminal receives the page, and
temporarily switches from the LTE system to the system with circuit-switched voice support, where the voice
call is received. Once the voice call is terminated, the terminal switches back to the LTE system.
done through the SGs interface between the MSC Server and the MME. The terminal receives the page, and
temporarily switches from the LTE system to the system with circuit-switched voice support, where the voice
call is received. Once the voice call is terminated, the terminal switches back to the LTE system.
For detailed feature description see, Cisco ASR 5000 Serving GPRS Support Node Administration Guide.
ISR Support for GPRS
With release 14.0, Idle Mode Signaling Reduction (ISR) support was introduced for UMTS network access. With
release 15.0, ISR support is now available for GPRS network access.
release 15.0, ISR support is now available for GPRS network access.
The ISR feature on the S4-SGSN provides a mechanism to optimize and/or reduce signaling load during inter-RAT cell-
reselection in idle mode (that is, in the ECM-IDLE, PMM-IDLE, and GPRS-STANDBY states). It is a mechanism that
allows the UE to remain simultaneously registered in a UTRAN/GERAN Routing Area (RA) and an E-UTRAN
Tracking Area (TA) list. This allows the UE to make cell reselections between E-UTRAN and UTRAN/GERAN
without having to send any TAU or RAU requests, as long as the UE remains within the registered RA and TA list.
reselection in idle mode (that is, in the ECM-IDLE, PMM-IDLE, and GPRS-STANDBY states). It is a mechanism that
allows the UE to remain simultaneously registered in a UTRAN/GERAN Routing Area (RA) and an E-UTRAN
Tracking Area (TA) list. This allows the UE to make cell reselections between E-UTRAN and UTRAN/GERAN
without having to send any TAU or RAU requests, as long as the UE remains within the registered RA and TA list.
ISR is a feature that reduces the mobility signalling and improves the battery life of UEs. ISR also reduces the
unnecessary signalling with the core network nodes and air interface. This is important especially in initial deployments
when E-UTRAN coverage will be limited and inter-RAT changes will be frequent.
unnecessary signalling with the core network nodes and air interface. This is important especially in initial deployments
when E-UTRAN coverage will be limited and inter-RAT changes will be frequent.
The benefit of the ISR functionality comes at the cost of more complex paging procedures for UEs, which must be
paged on both the registered RA and all registered TAs. The HSS also must maintain two PS registrations (one from the
MME and another from the SGSN).
paged on both the registered RA and all registered TAs. The HSS also must maintain two PS registrations (one from the
MME and another from the SGSN).
Important:
The Gn/Gp SGSN does not support ISR functionality.
Important:
The ISR feature requires a separate feature license. Contact your Cisco representative for licensing
information.
NAPTR-based Dynamic HSS Discovery
In releases prior to R15.0, the SGSN could contact a HSS only through static configuration of the HSS peer end point
through the HSS service. From Release R15.0 onwards, dynamic peer discovery is supported. The HSS address will be
resolved using NAPTR based DNS request-response method. The following commands have to be enabled for dynamic
peer discovery:
through the HSS service. From Release R15.0 onwards, dynamic peer discovery is supported. The HSS address will be
resolved using NAPTR based DNS request-response method. The following commands have to be enabled for dynamic
peer discovery:
In the Context Configuration Mode, the command
diameter endpoint < endpoint_name >
has to be
enabled.
In the Diameter Endpoint Configuration Mode, the command
dynamic-peer-discovery [ protocol {
sctp | tcp } ]
has to be enabled.
In the Diameter Endpoint Configuration Mode, the command
dynamic-peer-realm < realm_name >
has to
be enabled.