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

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

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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
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