Cisco Cisco ASR 5700
Mobility Management Entity Overview
Features and Functionality - Base Software ▀
MME Administration Guide, StarOS Release 18 ▄
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In compliance with 3GPP TS 29.172, the MME location services (LCS) feature supports sending the
EMERGENCY_CALL_RELEASE event in a subscriber location report (SLR) request message to the gateway mobile
location centre (GMLC) when an emergency call is released or when an emergency PDN is disconnected at the MME.
EMERGENCY_CALL_RELEASE event in a subscriber location report (SLR) request message to the gateway mobile
location centre (GMLC) when an emergency call is released or when an emergency PDN is disconnected at the MME.
With this new functionality, the MME notifies the GMLC of Emergency Call Release. The call release event enables the
GMLC to clear the cache for existing calls and to correctly log the duration of an emergency call. Without call release
facilitating the clearing of the cache, the location platform could send the old (erroneous) location information in
response to a new location request for an E-911 call.
GMLC to clear the cache for existing calls and to correctly log the duration of an emergency call. Without call release
facilitating the clearing of the cache, the location platform could send the old (erroneous) location information in
response to a new location request for an E-911 call.
Emergency Session Support
The MME supports the creation of emergency bearer services which, in turn, support IMS emergency sessions.
Emergency bearer services are provided to normally attached UEs and to UEs that are in a limited service state
(depending on local service regulations, policies, and restrictions).
Emergency bearer services are provided to normally attached UEs and to UEs that are in a limited service state
(depending on local service regulations, policies, and restrictions).
The standard (refer to 3GPP TS 23.401) has identified four behaviors that are supported:
Valid UEs only
Authenticated UEs only
IMSI required, authentication optional
All UEs
To request emergency services, the UE has the following two options:
UEs that are in a limited service state (due to attach reject from the network, or since no SIM is present), initiate
an ATTACH indicating that the ATTACH is for receiving emergency bearer services. After a successful
attach, the services that the network provides the UE is solely in the context of Emergency Bearer Services.
attach, the services that the network provides the UE is solely in the context of Emergency Bearer Services.
UEs that camp normally on a cell initiates a normal ATTACH if it requires emergency services. Normal attached
UEs initiated a UE Requested PDN Connectivity procedure to request Emergency Bearer Services.
EPS Bearer Context Support
Provides support for subscriber default and dedicated Evolved Packet System (EPS) bearer contexts in accordance with
the following standards:
the following standards:
3GPP TS 36.412 V8.6.0 (2009-12): 3rd Generation Partnership Project; Technical Specification Group Radio
Access Network; Evolved Universal Terrestrial Access Network (E-UTRAN); S1 signaling transport (Release
8)
8)
3GPP TS 36.413 V8.8.0 (2009-12): 3rd Generation Partnership Project; Technical Specification Group Radio
Access Network; Evolved Universal Terrestrial Radio Access Network (E-UTRAN); S1 Application Protocol
(S1AP) (Release 8)
(S1AP) (Release 8)
IETF RFC 4960, Stream Control Transmission Protocol, December 2007
EPS bearer context processing is based on the APN that the subscriber is attempting to access. Templates for all of the
possible APNs that subscribers will be accessing must be configured within the system. Up to 1024 APNs can be
configured on the system.
possible APNs that subscribers will be accessing must be configured within the system. Up to 1024 APNs can be
configured on the system.
Each APN template consists of parameters pertaining to how UE contexts are processed such as the following:
PDN Type: IPv4, IPv6, or IPv4v6
EPS Bearer Context timers