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LTE: How many timers being used to guard the LTE S1 handover procedure ?

+3 votes
1,856 views

Here two scenarios are possible:
- First scenario, target eNodeB and source eNodeB both have connection with same MME
- Second scenario, when both the eNodeBs are connected to different MMEs ?

posted Dec 19, 2015 by Harshita

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2 Answers

+1 vote

Below timers uses source eNB during s1 HO ...

TS1RELOCprep
- Specifies the maximum time for the Handover Preparation procedure in the source eNB.
TS1RELOCoverall
- Specifies the maximum time for the protection of the overall handover procedure in the source eNB.

answer Dec 20, 2015 by Veer Pal Singh Yadav
+1 vote

Just to add one more point here .

Source eNodeB starts TS1RELOCoverall timer once it receives "Handover Command" from the MME . Before that Handover Preparation timer i.e. TS1RELOCprep runs and source eNodeB stops this timer soon after "Handover command" receives.

answer Dec 20, 2015 by Vikram Singh
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