“Bearer” means “Carrier” which takes and carry the information from one point to another point or we can imagine this bearer as a pipe-line. EPS bearer or with long name Evolved Packet System bearer, provides user plane IP connectivity between UE and PGW.
An initial EPS bearer is established when the UE registers with the network using attach procedure and it is called “EPS Bearer Activation” procedure. This bearer is known as default EPS bearer. There are two kinds of EPS bearers which are Default and Dedicated. Details was explained in related tags. The Bearer is a virtual connection between UE and PGW.
EPS bearer is a combination of several sub bearers which are E-RAB bearer, Radio bearer, S1 bearer, S5 bearer and S8 bearer:
E-RAB bearer: transports the packets of an EPS bearer between UE and SGW.
Radio bearer: transports the packets of an EPS bearer between UE and eNodeB.
S1 bearer: transports the packets of an EPS bearer between an eNodeB and SGW.
S5/S8 bearers: transports the packets of an EPS bearer between SGW and PGW.
External bearer: transports the user packets between PGW and external networks.
Ziya,
How does the traffic gets leaked from the Tunnels in EPC and RAN ?
GTP
• Leak of user traffic
– to
Core Network (EPC)
– to
LTE RAN