Download - Gprs Attach Procedure
Signalling Message Flow for GPRS Attach
Presented By
Ben Caddick
Senior MPC Engineer
MS RNC SGSN HLR1. RRC Connection Establishment
1. UE sets up the necessary RRC (Radio Resourse Connections) in the RAN.
MS RNC SGSN HLR1. RRC Connection Establishment
2. Ue sends an attach request to the SGSN, identity used is the IMSI. We need to assume here that this is the first attach to the network and the
User has no such temporary identity available.
2. Attach (IMSI, DRX, CKSN, CN capability
MS RNC SGSN HLR1. RRC Connection Establishment
3. SGSN and UE perform necessary security procedures.
2. Attach (IMSI, DRX, CKSN, CN capability
3. Security Functions
MS RNC SGSN HLR1. RRC Connection Establishment
4. SGSN updates UE’s location to the HLR (IMSI, SGSN number, address).
2. Attach (IMSI, DRX, CKSN, CN capability
3. Security Functions
4. Update Location
MS RNC SGSN HLR1. RRC Connection Establishment
5. HLR sends Update Location Information to the SGSN, which duly acknowledges.
2. Attach (IMSI, DRX, CKSN, CN capability
3. Security Functions
4. Update Location
5. Insert Subscriber data
Acknowledge
MS RNC SGSN HLR1. RRC Connection Establishment
6. SGSN sends Update Location acknowledge.
2. Attach (IMSI, DRX, CKSN, CN capability
3. Security Functions
4. Update Location
5. Insert Subscriber data
Acknowledge
6. Update Location Ack
MS RNC SGSN HLR1. RRC Connection Establishment
7. SGSN sends Attach Accept to the UE. This contains new P-TMSI and P-TMSI signature, which the UE must acknowledge.
2. Attach (IMSI, DRX, CKSN, CN capability
3. Security Functions
4. Update Location
5. Insert Subscriber data
Acknowledge
6. Update Location Ack
7. Attach Accept
MS RNC SGSN HLR1. RRC Connection Establishment
8. The UE acknowledges receipt of Attach Accept with the Attach Complete Message.
2. Attach (IMSI, DRX, CKSN, CN capability
3. Security Functions
4. Update Location
5. Insert Subscriber data
Acknowledge
6. Update Location Ack
7. Attach Accept
8. Attach complete
MS RNC SGSN HLR1. RRC Connection Establishment
9. SGSN releases IU bearers.
2. Attach (IMSI, DRX, CKSN, CN capability
3. Security Functions
4. Update Location
5. Insert Subscriber data
Acknowledge
6. Update Location Ack
7. Attach Accept
8. Attach complete
9. IU Release
MS RNC SGSN HLR1. RRC Connection Establishment
10. RAN releases RRC connections.
2. Attach (IMSI, DRX, CKSN, CN capability
3. Security Functions
4. Update Location
5. Insert Subscriber data
Acknowledge
6. Update Location Ack
7. Attach Accept
8. Attach complete
9. IU Release
10. RAN releases RRC connections