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 MME TMSI (M‐TMSI), S‐TMSI

An M‐TMSI is allocated by the LTE/EPS MME to a UE. An S‐TMSI is constructed from an M‐TMSI and the MME code, which is 8 bits in length. Using the S‐TMSI, MME used to send a paging message to a UE. S‐TMSI has an end‐to‐end significance.

For a multi‐RATs capable UE/MS that supports the GSM, GPRS, UMTS, and LTE systems, a UE/MS will perform the combined registration procedures toward the respective CN. The concerned CN element will assign and allocate the three TMSIs accordingly, i.e. TMSI, P‐TMSI, and S‐TMSI, to a UE. For example, to notify an incoming CS call to an E‐UTRAN registered with the Circuit Switched Fall‐back (CSFB) feature, the MSC will send the paging request message to the MME with TMSI. The MME will send the paging command to the UE using the S‐TMSI. The UE will send the CS paging response with TMSI allocated by the MSC/VLR.

 Network Identities for LTE/EPS Network elements

Various identities are used to identify network elements or logical objects, at the protocol layer level, of an LTE/EPS network. Such network identities, as elucidated in Example 5.1 below, may be assigned as part of a periodical network planning or maintenance processes or can be generated and assigned by a network element dynamically to another network element as part of a protocol layer procedure.