"If you're not already familiar with Asterisk, it's primarily a
Linux based PBX (Private Branch eXchange) that supports multiple
telephone company related hardware cards, such as the Digium TE110P
and X100P, plus Voice over IP (VoIP).
"Linux VServers, sometimes known as Virtual Private Servers (VPS
(VPSes)), are a way for a single Linux machine to run multiple
instances of Linux..."