Does core network need to implement GTP-based or PMIP S5/S8 interface if it is combined S-GW/P-GW?

Question

Hi all

Because combined S-GW/P-GW is one node, so do we still need to implement the connection between them?
Is it necessary for core network to implement GTP-based or PMIP based S5/S8 interface if it is combined S-GW/P-GW?

Is there any 3GPP spec mention about combined S-GW/P-GW? what is the cons and reasons to do this?

thanks

Answer 1

To server small no of users, EPC Lite product can be used. EPC lite has all the necessary component of LTE network to provide LTE network services to its users. For emergency/defense services, network in a box is popular solution. Putting MME, SGW and PGW into a single box, does not mean all the interfaces such as S11, S1-U, S5/S8 have been merged. From the hardware point of view, all the nodes are packed together so that network can be deployed in fast manner.

Now coming to your question combining the SGW and PGW means, need to re-write application so that it can serve all the interfaces such as S11 towards MME and SGi towards external network. Traffic for S5/S8 interface would be mapped at the application level. It saves hardware cost and avoid data plane delay. Disadvantage what I realized is as part of mobility, # of handover messages will landed up more at the same combined node.

Comments

Thank you for your reply. So in this case, there is no two options in S5/S8 interface(GTP based or PMIP based)? Is there any spec talk about combined S-GW/P-GW?