Dedicated Bearer Activation - Knowledge Base
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11/2/2015 Dedicated Bearer Activation Knowledge Base data:text/html;charset=utf8,%3Cfont%20size%3D%224%22%3E%3Cb%3EDedicated%20Bearer%20Activation%3C%2Fb%3E%3C%2Ffont%3E%3Cdiv%3E… 1/1 Dedicated Bearer Activation The following diagram describes the steps the messages follow during the dedicated bearer activation procedure. 1. If the PDNGW has local QoS policy, then this step does not apply. However, if dynamic PCC is deployed, either the PCRF initiates IPCAN Session Modification procedure with the PCEF, or the PCEF initiates IPCAN Session Modification procedure with the PCRF. 2. The PDNGW uses the QoS Policy values i.e. QCI, ARP, GBR and MBR to assign to the EPS Bearer QoS. The PDNGW sends aCreate Bearer Request message to the SGW with the identities IMSI, PTI, EPS Bearer QoS, TFT, PGW S5/S8 TEID, Charging ID, default EPS Bearer Identity and PCO. 3. The SGW sends the Create Bearer Request message to the MME with the identities IMSI, PTI, EPS Bearer QoS, S1 TEID of SGW, TFT, default EPS Bearer ID and PCO. 4. The MME assigns a unique EPS Bearer Identity to the UE. The MME builds theSession Management Request (at the NAS layer) including PTI, TFT, EPS Bearer QoS, PCO, EPS Bearer Identity and default EPS Bearer ID. This message is encapsulated into a Bearer Setup Request message which includes EPS Bearer Identity, EPS Bearer QoS, Session Management Request and S1 TEID, and sends to the eNodeB. 5. The eNodeB maps the EPS Bearer QoS to the Radio Bearer QoS and signals an RRC Connection Reconfiguration message to the UE which includes the identities EPS Radio Bearer Identity, Radio Bearer QoS, Session Management Request. At the NAS Layer, the UE stores the EPS Bearer ID and links the dedicated bearer to the default bearer. The UE also retrieves the Uplink TFT and uses it to determine the mapping of traffic flows to the radio bearer. 6. The UE acknowledges the radio bearer activation to the eNodeB using an RRC Connection Reconfiguration Completemessage. 7. The eNodeB acknowledges the bearer activation to the MME using the Bearer Setup Response message which includes the EPS Bearer Identity and S1 TEID. The UE also builds a Session Management Response message at the NAS Layer including the EPS Bearer Identity. The UE then sends a Direct Transfermessage to the eNodeB which includes the Session Management Response message. The eNodeB sends an Uplink NAS Transportmessage to the MME which includes the Session Management Response message. 8. Upon receipt of Bearer Setup Response and Session Management Response messages, the MME sends Create Bearer Response (EPS Bearer Identity, eNodeB S1TEID) message to the SGW. 9. The SGW sends Create Bearer Response (EPS Bearer Identity, SGW S5/S8TEID) message to the PDNGW. 10. The PDNGW responds to the PCRF allowing the completion of IPCAN Session Modification procedure.
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Transcript of Dedicated Bearer Activation - Knowledge Base
11/2/2015 Dedicated Bearer Activation Knowledge Base
data:text/html;charset=utf8,%3Cfont%20size%3D%224%22%3E%3Cb%3EDedicated%20Bearer%20Activation%3C%2Fb%3E%3C%2Ffont%3E%3Cdiv%3E… 1/1
Dedicated Bearer Activation
The following diagram describes the steps the messages follow during the dedicated bearer activation procedure.
1. If the PDNGW has local QoS policy, then this step does not apply. However, if dynamic PCC is deployed, either the PCRF initiates IPCAN SessionModification procedure with the PCEF, or the PCEF initiates IPCAN Session Modification procedure with the PCRF.
2. The PDNGW uses the QoS Policy values i.e. QCI, ARP, GBR and MBR to assign to the EPS Bearer QoS. The PDNGW sends aCreate BearerRequest message to the SGW with the identities IMSI, PTI, EPS Bearer QoS, TFT, PGW S5/S8 TEID, Charging ID, default EPS Bearer Identity andPCO.
3. The SGW sends the Create Bearer Request message to the MME with the identities IMSI, PTI, EPS Bearer QoS, S1 TEID of SGW, TFT, default EPSBearer ID and PCO.
4. The MME assigns a unique EPS Bearer Identity to the UE. The MME builds theSession Management Request (at the NAS layer) including PTI, TFT,EPS Bearer QoS, PCO, EPS Bearer Identity and default EPS Bearer ID. This message is encapsulated into a Bearer Setup Request message whichincludes EPS Bearer Identity, EPS Bearer QoS, Session Management Request and S1 TEID, and sends to the eNodeB.
5. The eNodeB maps the EPS Bearer QoS to the Radio Bearer QoS and signals an RRC Connection Reconfiguration message to the UE which includesthe identities EPS Radio Bearer Identity, Radio Bearer QoS, Session Management Request. At the NAS Layer, the UE stores the EPS Bearer ID and linksthe dedicated bearer to the default bearer. The UE also retrieves the Uplink TFT and uses it to determine the mapping of traffic flows to the radio bearer.
6. The UE acknowledges the radio bearer activation to the eNodeB using an RRC Connection Reconfiguration Completemessage.
7. The eNodeB acknowledges the bearer activation to the MME using the Bearer Setup Response message which includes the EPS Bearer Identity and S1TEID.
The UE also builds a Session Management Response message at the NAS Layer including the EPS Bearer Identity. The UE then sends a DirectTransfermessage to the eNodeB which includes the Session Management Response message. The eNodeB sends an Uplink NAS Transportmessage tothe MME which includes the Session Management Response message.
8. Upon receipt of Bearer Setup Response and Session Management Response messages, the MME sends Create Bearer Response (EPS Bearer Identity,eNodeB S1TEID) message to the SGW.
9. The SGW sends Create Bearer Response (EPS Bearer Identity, SGW S5/S8TEID) message to the PDNGW.
10. The PDNGW responds to the PCRF allowing the completion of IPCAN Session Modification procedure.
