top button
Flag Notify
    Connect to us
      Site Registration

Site Registration

What are the key differences between S1 and X2 handover, besides the devices/protocols involved?

+4 votes
3,711 views
What are the key differences between S1 and X2 handover, besides the devices/protocols involved?
posted Mar 28, 2015 by anonymous

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

1 Answer

+1 vote

Handover may be triggered between eNodeBs due to following reasons:
1. Load balancing : One eNodeB is overloaded and another eNodeB is under utilized
2. UE is moving away from connected cell and giving measurement reports of possible target cells.

X2 handover is faster as compared to S1. X2 handover is defined only for intra LTE handover while S1 handover can be used for intra LTE, inter RAT. S1 handover has variations like "handover with MME & SGW relocation", "handover with MME relocation only", "handover with SGW relocation only" , handover without MME and SGW change, where as X2 provides variants like "handover with SGW relocation" and "handover without SGW relocation".

answer Mar 29, 2015 by Harshita
Similar Questions
+2 votes
When and where data buffer will start during x2 and s1 handover and when it will forward to target cell

Please explain in detail "When and where data buffer will start during x2 and s1 handover and when it will forward to target cell"

+4 votes
How target enodeb will validate the new incoming user during x2 or s1 handover?

How target enodeb will confirm if the incoming user is a genuine user or not?

Is there any IE exchanged during HO preparation phase? I am expecting that during X2 handover AS SECURITY INFO in UE context is very helpful? Is that or not?

+1 vote
Would there be an advantage of X2 based handover over S1 based handover, when X2 physically spans the same path as S1?

In case of hub-and-spoke topology, X2 messaging can travel all the way back to an aggregation point, which may be co-located with EPC. In such scenario both X2 and S1 traverses same physical path (a.k.a X2 over S1). Please consider both Intra-MME and Inter-MME handover scenarios. Would X2 based handover in such a case yield advantage over S1 based handover. Thanks.

...