How many DRBs can 1 EPS Bearer Support?

4G LTE
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1

How many DRBs can 1 EPS Bearer Support?

2

I think 8 DRB per EPS bearer.

3

Only 1 DRB per EPS bearer in LTE

4

Hi brother.
Are u sure about this? i think as long multiple DRBs requirement does not exceed the QoS profile of a EPS bearer it will support multiple DRBs.

However i cannot understand the below sentence. Please let me know the exact meaning.

The DRB ID is assigned by an eNB upon establishment of the EPS bearer, and is mapped with EPS bearer IDs on 1:1 basis

5

Ok Thanks bro.
Any source??

6

3GPP TS 36.300 section 13.1

7

I think UE support 1DRB per EPS, and max 8 EPS with 8 DRB.
Some vendors require license for 8DRB.

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8

In LTE, EPS Bearer is mapped 1:1 to DRB.
Refer to 3GPP 36.300, section on QoS for more details.

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9

As seen form above figure posted by [gkreddy] the EPS bearer is a concatenation of three bearers: DRB, S1 and S5. So it makes sense that one EPS bearer doesn’t fit more than one DRB. With other words imagine EPS bearer as a large pipe made by three small pipes, one of those is DRB pipe. While different EPS sessions can be handled by one DRB within the EPS bearer.

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10

Concatenation of Radio Bearer (DRB in this case) on air interface + S1 bearer on S1-U interface + S5/S8 bearer on S5/S8 is called EPS bearer.

Not just in air interface, throughput it is 1:1 mapped (upto PGW).

It is not 3 pipes, it is a single pipe with concatenation.

11

Thank you for correcting. I miss expressed as had in mind a linear pipe segmented in three parts.

12

thanks bro

13

Thanks brother . However doubt arises due to Handover request over X2 interface.
we send ERABs to be setup(ERAB ID,QCI) for multiple ERAB, However only a single S1 SGW TEID IS sent.
how can a single TEID be used for Multiple bearers.??.