Protocol Entities |
기능 |
CC: Call Control |
- Setup and release calls - Manage multiple call contexts |
SS: Supplementary Service |
- Call barring, Call waiting, Call forwarding |
SMS: Short Message Service |
- SMS-MT, SMS-MO - 160 ASCII characters can be delivered to MS even during communication |
MM: Mobility Management |
- Perform authentication, ciphering, and location updates - Read and write SIM data - Relay CC layer messages |
RR: Radio Resource |
- Monitoring neighbour cells and cell re-selection - Channel request/assignment/release - Measurement reports from mobile |
DL: Data Link |
- Organization of layer3 information into frames - Acknowledgement of transmission and reception of numbered information frames |
SIM: Subscriber Identity Module |
- Provide user identity and/or terminal identity to MM for the authentication - Provide ciphering key information - Store the last location area information |
Protocol Entities |
Functions |
SNDCP: Sub-Network Dependent Convergence Protocol |
- All functions related to the transfer of Network layer Protocol Data Units(N-PDUs) - Improve channel efficiency by means of compression techniques |
SM: Session Management |
- PDP Context Activation - PDP Context Deactivation - PDP Context Modification |
GSMS: GPRS Short Message Service |
- SMS-MT, SMS-MO - 160 ASCII characters can be delivered to MS even during communication |
GMM: GPRS Mobility Management |
- GPRS authentication/ciphering - GPRS attach/detach - Routing area updating |
LLC: Logical Link Control |
- Variable-length information frames - ACK/NACK data transfer - Flow and sequence control |
GRR: GPRS Radio Resource |
- RLC: Reliable radio-solution dependent link - MAC: Mapping of LLC frames to GSM physical channel |
Protocol Entities |
Functions |
USM: UMTS Session Management |
- PDP Context Activation - PDP Context Deactivation - PDP Context Modification |
UMM: UMTS Mobility Management |
- UMTS authentication/ciphering - UMTS attach/detach - Routing area updating |
RABM: Radio Access Bearer Management |
- Management concepts of RABs that can be activated /released while a PDP context is active. |
RRC: Radio Resource Control |
- Perform cell selection, measurement reporting, and handover - Establish RRC connection for signaling and release it - Assign radio resources for radio bearers - Relay CC and MM layer messages |
PDCP: Packet Data Convergence Protocol |
- Header compression and decompression of IP data streams - Transfer of user data (NAS <-> RLC) - Multiplexing of different RBs onto the same RLC entity |
BMC: Broadcast/Multicast Control |
- Storage of Cell Broadcast Messages - Scheduling of BMC messages |
RLC: Radio Link Control |
- Establish and release a radio link - Segment and re-assembly CC, MM, RRC layer messages and relay them - Keep the radio link reliable performing error recovery |
MAC: Medium Access Control |
- Multiplex and de-multiplex RLC frames into appropriate channels - Guarantee the pre-specified data rates of channels |
USIM: UMTS Subscriber Identity Module |
- Provide user identity and/or terminal identity to UMM for the authentication - Provide ciphering key information - Store the last location area information |