Do I need a fullmesh topology between branches for voip calls?

Question

Computer networks

Hello, now there is a choice between two topologies for organizing vpn between branch networks. Star is cheaper, fullmesh is more expensive, but to be honest I don't have a good reason for fullmesh, because access is needed mainly from branches to the central heating center, and not vice versa, because applications are all client-server. But I'm afraid that in the future, due to the transition to voip telephony, I will have to switch to a fullmesh topology.
Question: When making voip calls, does voice traffic go through an intermediary server (for example, asterisk in the central office) or directly?

Answer 1

A small jitter and the absence of losses are important .. And how you achieve this is the tenth thing.

Answer 2

it is desirable to start up the voice directly, tk. you will not depend on the loading of channels in the center and its availability generally
depends on how telephony will be implemented
if one central server and recording of conversations is not needed, you can start p2p voice between
clients
a mixed version is possible
there is no need to use one thing, both centralized and full mesh can be parallel