ENodeB connection with UMTS Core network?

Question

Is there any possibility where eNB is connected with the UMTS core network i.e. SGSM/MSc or is it via EPC only.

Answer 1

I think "No", unless UMTS core is upgraded to EPC.

Below are some of the differences between UMTS and LTE network:

i) UMTS Core network does not even directly connect to UMTS NodeB, rather it connects to RNC and inturn RNC connects to NodeB. Where as eNodeB directly connects to EPC nodes (MME & SGW) and does not require RNC like component.
ii) LTE adapts and flat network architecture as opposed to hierarchical network architecture in UMTS. This results in a different functional distribution in LTE core nodes as compared to UMTS core nodes.
iii) The protocol stack between Base Station (NodeB or eNodeB) and Core Network is different in the case of UMTS and LTE.

If UMTS core nodes can upgrade to support EPC functionality then eNodeB can connect to the same.
However in such case the upgraded core will no longer be UMTS core network rather will be Converged Evolved Packet Core.