Cisco ASR 5000 series Product Overview page 885

Mobility Management Entity Overview
Figure 210. User-initiated Service Request Message Flow
Random Access procedure
1
RRC Connection Request
2
(Service Request)
Contention resolution
RRC Connection Reconfiguration
RRC Connection
Reconfiguration Complete
NAS Security Mode Command
8
(security algorithm)
NAS Security Mode Complete
RB_Establishment Request
11
RB_Establishment Response
1. UE and eNodeB performs Random Access procedure.
2. UE sends service request (RRC Connection Request) to eNodeB.
3. eNodeB forwards Service request in Initial UE message to MME.
4. eNodeB preforms contention resolution with UE
5. eNodeB starts RRC connection reconfiguration.
6. eNodeB sends RRC Connection Request Complete and Reconfiguration Complete message to UE.
7. Authentication procedure starts between UE, MME and HSS.
8. eNodeB sends NAS Security Mode Command to UE with selected algorithm.
9. UE sends NAS Security Mode Complete Command to eNodeB.
10. MME sends initial Context Setup Request to eNodeB with radio bearer QoS, security algorithm etc.
11. eNodeB sends RB_Establishment Request to UE.
12. UE sends RB_Establishment Response to eNodeB and radio bearer established.
13. eNodeB sends initial Context Setup Request Response to MME.
14. MME sends Modify Bearer Request to S-GW.
OL-22938-02
eNodeB
Initial UE message
(Service Request)
4
5
6
Authentication (the AKA procedure)
9
Initial Context Setup Request
(RB QoS, Security algorithm)
12
Initial Context Setup
Complete
MME
3
7
10
13
Update Bearer Request
Update Bearer Response
15
Cisco ASR 5000 Series Product Overview ▄
How MME Works ▀
HSS
Serving GW
14