Cisco Cisco ASR 5700
Mobility Management Entity Overview
▀ Features and Functionality - Base Software
▄ MME Administration Guide, StarOS Release 18
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Load balancing is achieved by setting a weight factor for each MME so that the probability of the eNodeB selecting an
MME is proportional to its weight factor. The weight factor is typically set according to the capacity of an MME node
relative to other MME nodes. The weight factor is sent from the MME to the eNodeB via S1-AP messages.
MME is proportional to its weight factor. The weight factor is typically set according to the capacity of an MME node
relative to other MME nodes. The weight factor is sent from the MME to the eNodeB via S1-AP messages.
Refer to the Load Balancing and Rebalancing chapter for more information about this feature.
MME load balancing can be used in conjunction with congestion control. For more information on congestion control,
refer to the
refer to the
Load Re-balancing
The MME load re-balancing functionality permits UEs that are registered on an MME (within an MME pool area) to be
moved to another MME.
moved to another MME.
The rebalancing is triggered using an exec command on the mme-service from which UEs should be offloaded.
When initiated, the MME begins to offload a cross-section of its subscribers with minimal impact on the network and
users. The MME avoids offloading only low activity users, and it offloads the UEs gradually (configurable from 1-1000
minutes). The load rebalancing can off-load part of or all the subscribers.
users. The MME avoids offloading only low activity users, and it offloads the UEs gradually (configurable from 1-1000
minutes). The load rebalancing can off-load part of or all the subscribers.
Refer to the Load Balancing and Rebalancing chapter in the MME Administration Guide for more information about
this feature.
this feature.
Local Cause Code Mapping
Local cause code mapping provides the operator with the flexibility to ignore the default EPS Mobility Management
(EMM) cause code and to configure a preferred EMM cause code to be sent to a UE in response to a procedural failure.
For example, the operator can instruct the MME to return one of six different EMM cause codes other than the default
when the context received from a peer SGSN (during a TAU procedure) does not contain any active PDP contexts.
(EMM) cause code and to configure a preferred EMM cause code to be sent to a UE in response to a procedural failure.
For example, the operator can instruct the MME to return one of six different EMM cause codes other than the default
when the context received from a peer SGSN (during a TAU procedure) does not contain any active PDP contexts.
Local cause code mapping can be configured in either or both the MME-Service configuration or in the Call-Control
Profile configuration. Refer to these two configuration modes in the Command Line Interface Reference to see the
current list of
Profile configuration. Refer to these two configuration modes in the Command Line Interface Reference to see the
current list of
local-cause-code-mapping
commands.
Management System Overview
The system's management capabilities are designed around the Telecommunications Management Network (TMN)
model for management - focusing on providing superior quality network element and element management system
functions. The system provides element management applications that can easily be integrated, using standards-based
protocols (CORBA and SNMPv1, v2), into higher-level management systems - giving wireless operators the ability to
integrate the system into their overall network, service, and business management systems. In addition, all management
is performed out-of-band for security and to maintain system performance.
model for management - focusing on providing superior quality network element and element management system
functions. The system provides element management applications that can easily be integrated, using standards-based
protocols (CORBA and SNMPv1, v2), into higher-level management systems - giving wireless operators the ability to
integrate the system into their overall network, service, and business management systems. In addition, all management
is performed out-of-band for security and to maintain system performance.
The Operation and Maintenance module of the system offers comprehensive management capabilities to the operators
and enables them to operate the system more efficiently. There are multiple ways to manage the system either locally or
remotely using its out-of-band management interfaces.
and enables them to operate the system more efficiently. There are multiple ways to manage the system either locally or
remotely using its out-of-band management interfaces.
These include:
Using the command line interface (CLI)
Remote login using Telnet, and Secure Shell (SSH) access to CLI through SPIO card's Ethernet management
interfaces
Local login through the Console port on SPIO card using an RS-232 serial connection