| msc { |
| hscale=2; |
| UE, ENB [label="eNodeB"], BSS, MME, VLR [label="MSC/VLR"], HSS [label="HSS/HLR"]; |
| |
| UE => MME [label="NAS Extended Service Request"]; |
| ENB <= MME [label="S1-AP UE Context Mod Req with CSFB"]; |
| ENB => MME [label="S1-AP UE Context Mod Resp"]; |
| UE <= ENB [label="NACC (Network Assisted Cell Change)"]; |
| ENB => MME [label="S1-AP S1 UE Context Release Req"]; |
| UE box MME [label="S1 UE Context Release"]; |
| |
| UE box HSS [label="UE changes RAT then LA and/or RA update"]; |
| UE <=> HSS [label="PS Suspend (TS 23.060)"]; |
| |
| UE => BSS [label="CM SERV REQ"]; |
| BSS => VLR [label="COMPL L3 (CM SERV REQ)"]; |
| UE <=> VLR [label="Normal 2G Voice Call"]; |
| } |