When it comes time to upgrade your smartphone, most people just want convenience. Here's why (and where) you should sell your phone for top dollar.
1. For example, in order to facilitate VoIP communications, the communications system 100, the MSC 102, and local exchange 104 For example, may include additional application servers, media servers, service brokers, call agents, edge routers, gateways (signaling, trunking, access, sub, etc.), ...