Giving VoIP Traffic the Green Light, Part 2
Beginning the Configuration
Last week we covered TCP/IP networking basics. The more you know about the care and feeding of TCP/IP the better, so don't stop with my very basic overview.
Today we're going to configure our Internet router/gateway to give priority to Asterisk traffic. This how-to is for admins who have nice sturdy Linux-based Internet gateways. If you're using a commercial router with its own operating system, like Cisco, you'll have to learn the traffic-shaping incantations peculiar to it.
Indeed, while Cisco, Linksys, Netgear, Zyxel, et al, make excellent routers and Internet gateways, you can easily duplicate or exceed their functionality with Linux on ordinary x86 hardware for a fraction of the cost, for all but the most high-demand routing. In other words, if you're not AT&T or an ISP, Linux will do everything you need and more.
If you're wondering about terminology like "router" and "gateway," let's define them so we're all on the same page. A router is any device that enables traffic to pass between networks, like between the Internet and your LAN, or different subnets on your LAN. A gateway does routing, and also includes other border services like firewalling, intrusion detection, HTTP caching/filtering, and whatever else the network administrator thinks is needed to guard the borders.