How much DRBs can we have for a single UE?

Hi all 5G / LTE Experts.

For one single UE, how much DRBs can we have?

And when we say DRB we are implicitly saying that all PDU sessions shall be with same QCI of that DRB?

There can be 8 DRB.

Can also be different QCI in one DRB.

What do you mean by different QCI?

Hi all 5G Experts.

Can we have more than one DRB per one PDU session for same single UE?

Yes, we can.

Like let’s say PDU session for internet services … let’s say youtube.

Other PDU session could be for what?

Hi I think the picture below answer your question, we can have many DRB per User and each DRB. Different service


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LTE feature max 8 DRB.

1 default + 7 dedicated for that PDN.

8 DRB in LTE.
Max 3 DRB can be UM.

There is also a limitation on number PCRF traffic filters per APN per device.

Can you please elaborate it?

Yes. Traffic filtering is done by PCEF.

Can you please elaborate it?

In EPS (4G) there is limitation of number of traffic filtering rules which can be defined per APN in PCRF.

Limit is 16 so for a given APN you can either define 8 bearers which 2 traffic filter each (DL and UL) or you can have 1 bearer with 16 different filters (unlikely but still possible).

Don’t know whether this limitation was changed in 5G Core.


Please, in which spec can I refer for this?

Ooh that’s difficult to find.

But I have pretty much checked and validated this myself.

I will try to find reference for this…

For 4G, refer to 36.331, B1. For 5G I only find maxdrb = 29, in 38.331.

I see on specs it’s 32 DRBs per one PDU session, right?

Now, how much PDU sessions we can have per single UE?

Up to 4 PDU session per UE?

I mean in terms of UE - looking at PDU session level - how much the maximum PDUs of single UE can support?

The number of Dedicated Radio Bearers (DRBs) that can be established for a single User Equipment (UE) depends on various factors, including the capabilities of the network, the UE, and the specific use case.

In LTE networks, typically up to 11 DRBs can be established for a UE, but this can vary based on network configurations and standards.

Keep in mind that the number of DRBs can evolve with advancements in technology and network deployments.