top button
Flag Notify
    Connect to us
      Site Registration

Site Registration

Handover form 4g to other network (3G, 2G, WiFi)

+4 votes
1,379 views

I am unable to get complete signaling flow of handover from LTE to other network like 3g, 2g, wifi network.

I want to understand complete flow of handover from mobile (From LTE network) to other mobile (to other network like 3g, 2g, wifi network).

posted Dec 11, 2013 by anonymous

Share this question
Facebook Share Button Twitter Share Button LinkedIn Share Button

1 Answer

+1 vote

Its difficult to answer in one question, what you want the 3GPP and non-3GPP handover & handover to trusted and non-trusted handover.

Please have a look at the following specs

Spec 3GPP TS 23.401 V11.7.0 .
Spec 3GPP TS 23.402 V10.7.0 .
Spec 3GPP TS 24.302 V11.7.0

answer Dec 12, 2013 by Satish Mishra
Similar Questions
+3 votes
4G to 2G Handover (HSS-MME)

When subscriber moves from 4G to 2G network, will HSS send CLR to MME? If it doesn't, in that case how does it know that the UE is no longer attached to MME?

+3 votes
VoLGA: Call flow for Handover from E-UTRAN(4G) to GERAN (2G) procedure?

Assume that DTM handover is supported in the target GERAN.

+4 votes
3G to 4G Handover without S6d interface?

We have found an interesting scenario we would like you to share with the SGSN and HSS experts .

Below Description of scenario
When the user moves from X SGSN to MME (3G to LTE network), X SGSN is never informed of this RAT TYPE change, and it keeps a false entry for this user in the SGSN despite it's not attached to the 3G network anymore. However, the HLR knows the UE is not attached anymore to the 3G network, because the SGSN number and address cannot be seen anymore from the HLR GUI after the RAT TYPE change is completed. We think this might be one of the main reasons why we see more users attached to the 3G network in X SGSN than those we see in the HLR.
We think this is happening because the HSS-FE removes the SGSN number and address itself from the HSS when it receives the ULR from MME. However, it cannot send a CANCEL LOCATION to X SGSN because S6D interface is not available .

In order to make myself clear, you can find more comments below about the scenario.
1) The UE is attached to the 3G network, that is, it’s attached to SGSN
2) It moves from SGSN to our MME (from 3G to LTE). The MME sends the LOCATION UPDATE via S6A interface towards the HSS.
3) However, the CANCEL LOCATION is never received by our SGSN because the S6D interface between the HSS-FE and the SGSN is not implemented in our network. Therefore, the SGSN does not know that this user moved from 3G to LTE, and keeps the record in the SGSN. On the other hand, the SGSN number and address are removed from the HLR, and we think this is done by the HSS-FE itself.?
4) The SGSN keeps the record while the HLR don't, which creates a difference in the number of subscriber attached to the 3G network between the SGSN and the HLR. The SGSN sees more subscribers attached to the 3G than those seen by the HLR.

Could you please confirm that you have now a clear picture of what the issue is?

Could you please provide your recommendations in order to fix this issue?
Is't S6d interface is mandatory for this scenario?

If you have any question, please, let me know.

+2 votes
Handover from 3G to 4G while UE in connected state?

I know its possible to handover to 3G from 4G in connected state.

But do networks implemented the backwards, I mean 3G to 4G while UE in connected state?? Reselection happens for me but not Handover ?? When UE goes to Cell_PCH or IDLE state it moves back to 4G, not when I am streaming or downloading.

...