128K eNodeB Connection Support
The MME now supports 128K eNodeB connections for VPC-DI and ASR5500-DPC2 platforms; it has been enhanced from 64K eNodeB connections. A MME manager instance supports 4K eNodeBs, a minimum of 32 MME managers are required to support 128K eNodeB's. If the network has more than 32 MME managers, 128k eNodeB connections limit is not enforced. The support for 128K eNodeB connections is per chassis and not per MME service.
The maximum number of MME managers that can be configured per chassis for the VPC-DI platform has been enhanced from "24" to "48".
Distribution of Multiple SCTP Association - VLR
The SCTP associations of a VLR are now distributed across MME managers. In previous releases multiple SCTP connections from a VLR were hosted on the same MME manager. Distribution of VLR SCTP associations across MME managers helps in achieving better load distribution at the MME managers.
There is no change for load balancing of SGs messages sent by MME across multiple SCTP associations of a VLR.
S1-SCTP Rate Limiting
The operator can now configure a rate limit for incoming S1 SCTP connections from the eNodeB. This prevents an overload at the MME in case there is a surge of S1 SCTP connections from the eNodeBs. New command keywords s1-sctp rate limit are introduced in the task facility mmedemux command, they can be used to specify the rate limit value of connections per second for the chassis. New MME Demux subsystem statistics are introduced to display the number of packets that are dropped due to the configured rate limit.