How it Works

Important

The CEPS optimization with GTPv2 CEPs works only with System mode shutdown and restart. It is not recommended to use this with Rolling Software Update as it may lead to system inconsistency.

Cache

At the udp-proxy pod, a cache is maintained. This cache contains entries corresponding to sessions that require GTP protocol for interaction with other nodes in network. Each cache entry is mapped to TEID assigned to the corresponding session by SMF. The cache entry contains details remote session TEID, EBI, TEID allocated by SMF and last sequence number.

There is a limit on the number of cache entries that can be added in the cache. The limit is around a million cache entries. Stale(cache entries that are not used for an hour) cache entries are periodically removed from the cache.

Short Circuit

On receiving an incoming UDP packet, SMF identifies if the message is a request message. It lookups the cache to see if there is corresponding cache entry present.

If the cache entry is present and the request is MBR and if it short circuited, then MBR response is generated without full processing.

The conditions for short circuiting MBR are as follows:

  • MBR comprising of only Serving Network IE

  • MBR comprising of Serving Network IE and Bearer Context with EBI only

  • MBR comprising of Serving Network IE and Indication IE with other than HO (Handover) bit set