Hello everyone！
Today, I'd like to introduce some information about EPS bearers.
What Is EPS Bearer?
In EPS, the bearer is the basic granularity of QoS.
The EPS bearer uniquely identifies all service flows with the same QoS between the UE and the serving gateway. That is, all service data flows mapped to the same EPS bearer receive the same data transmission processing, that is, the same QoS guarantee. Different EPS bearers are required to provide data transmission at different bearer levels.
EPS bearer category
EPS bearers are classified into the following types based on the setup time:
Default bearer
In the EPS system, a bearer is always established during the PDN connection to provide an always-on IP connection for the UE. This bearer is called the default bearer.
Dedicated bearer
Other EPS bearers connected to the same PDN are called dedicated bearers. The creation or modification of dedicated bearers can only be initiated by the network layer, and bearer-level QoS parameters are always allocated by the packet core network.
Dedicated bearer setup scenario
When a UE needs to access a specific service, a dedicated bearer needs to be set up between the UE and the core network.
A dedicated bearer can be set up only by the network side, but the UE can trigger the network side to set up a dedicated bearer.
Figure 1 Dedicated bearer setup scenario
EPS bearers can be classified into the following types based on whether GBR is available:
Non-GBR bearer
If no dedicated network resources are allocated to an EPS bearer to ensure the GBR of the EPS bearer, the EPS bearer is called a non-GBR bearer. For example, email, SFTP, HTTPS, etc.
GBR bearer
If dedicated network resources are allocated to an EPS bearer to ensure the GBR of the EPS bearer, the EPS bearer is called a GBR bearer. such as voice, video, and real-time gaming.
That's what I'm sharing about EPS bearer and I'll be sharing TAU in my next post.
Welcome to read and comment!
