· The purpose of the dedicated EPS bearer context activation procedure is to establish an EPS bearer context with a specific QoS and TFT between the UE and the EPC.
· A PDN connection consists of one Default EPS bearer and, depending on the service for which the connection is used, a number of dedicated EPS bearers.
· FYI.., a default EPS bearer is established during the Attach or Standalone PDN Connectivity procedure. Any additional EPS bearer that is established for the same PDN connection is referred to as a dedicated EPS bearer. Dedicated EPS bearers are activated and deactivated depending on the service used but the default bearer remains established throughout the lifetime of the PDN connection. The network decides if dedicated bearers need to be setup or not and what QoS settings should be applied for the dedicated bearers.
· The dedicated EPS bearer can be either guaranteed bit rate (GBR) or non-GBR.
· The dedicated EPS bearer context activation procedure is initiated by the NW, but may be requested by the UE by means of the UE requested bearer resource allocation/modification procedure.
· This procedure can be part of the attach procedure or be initiated together with the Default EPS bearer context activation procedure when the UE initiates a stand-alone PDN connectivity procedure.
· If the attach procedure or the Default EPS bearer context activation procedure fails, then the UE shall consider that the dedicated bearer activation has implicitly failed.
· The MME shall initiate the dedicated bearer context activation procedure by sending an ACTIVATE DEDICATED EPS BEARER CONTEXT REQUEST message and start the timer
· The MME allocates and includes the EPS Bearer Identity in the ACTIVATE DEDICATED EPS BEARER CONTEXT REQUEST message.
· The MME shall include the EPS bearer identity of the associated default bearer as the Linked EPS Bearer Identity in the ACTIVATE DEDICATED EPS BEARER CONTEXT REQUEST message.
· If this procedure was initiated by a UE requested bearer resource allocation/modification procedure, the ACTIVATE DEDICATED EPS BEARER CONTEXT REQUEST message shall contain the Procedure Transaction Identity (PTI) value received by the MME from the UE
· The other IEs in the ACTIVATE DEDICATED EPS BEARER CONTEXT REQUEST include EPS QoS, Traffic Flow Template (TFT), Transaction Id, Negotiated QoS, Negotiated LLC SAPI, Radio Priority, Packet flow Id, Protocol configuration options etc…
Reference 3GPP TS 24.301
Example: ACTIVATE DEDICATED EPS BEARER CONTEXT REQUEST message
I have a doubt on UE initiated dedicated bearer. As you have mentioned it can be part of attach procedure ( attach + pdn connection request ). Which content of the message will say UE need dedicated bearer ?
ReplyDeleteI did not notice any parameters on PDN connectivity request / attach request.
Can you help me to understand the same ?
Dear,
ReplyDeleteIn my case during activation of dedicated bearer QCI1, i have "" Linked EPS Bearer Id: 6"". i expected to be linked to QCI 5 which is IMS and not 6.
QCI6 is used in my Network for default APN INTERNET.
Can any one explain why i get linked to 6 and not to 5 ? Thank you.
Dear
ReplyDeleteyou said:
" The MME allocates and includes the EPS Bearer Identity in the ACTIVATE DEDICATED EPS BEARER CONTEXT REQUEST message."
Does this EPS Bearer Identity is the QCI1 ?
In my case during the activation of dedicated EPS Bearer is not set to 1 (it's 7, but QCI1 is established).
hi,
ReplyDeleteI have question : if the device is rel 10 but support the QC MCPTT, how the network can accept the beraer request
Great Blog, there is so much reality written in this content and everything is something which is very hard to be argued. Top notch blog having excellent content. dedicated internet connection
ReplyDeleteHas anyone been able to establish a UE initiated dedicated bearer using AT commands? I have been following (3GPP TS 27.007 version 10.3.0 Release 10) to no avail.
ReplyDeleteThanks!
Jack
I have a question: in case os establishment of dedicated bearers for video call "ACTIVATE DEDICATED EPS BEARER CONTEXT REQUEST" requests activation of bearers with two QCIs- QCI1 and QCI-2. Is there any specification that describes the order of QCIs in the request? The issue is that MME sets qci-2 first and qci-second, and UE accepts bearer activstion only for qci-2
ReplyDeleteI am a regular reader of your blog, Amazing content with proper examples. Thank you admin. dedicated internet access
ReplyDelete