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What is X2-based handover with Serving GW relocation in LTE?

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What is X2-based handover with Serving GW relocation in LTE?
posted Dec 16, 2014 by Gnanendra Reddy

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1 Answer

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This procedure is used to handover a UE from a source eNodeB to a target eNodeB using X2 when the MME is unchanged and the MME decides that the Serving GW is to be relocated. Following is the call flow -

x2 based handover with SGW relocation


answer Dec 16, 2014 by Salil Agrawal
will you explain when S-gw changes in this scenario where mme is only one?
I dont know the exact reason just making a Guess on what basis MME decides SGW to be changed -
1. Current SGW connected to  the eNB does not have connection with new eNB, which is in same MME pool area.
2. Load factor (less likely)
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