A router’s window to internetwork is throughout its ports and modules. Without them, a router is a worthless box. The ports and modules that are place into a router define what it can do.

Internetworking can be scary, with the apparently endless combinations of products, protocols, media, feature sets, standards. The acronyms come so quick and so hard that it might look bad to learn how to correctly organize a router. But choosing the right router product can be boiled down to handy proportions. Table lays out five main requirement areas that, if met, will lead you to the best router solution.

Cisco clearly can’t produce a model of router to match each customer’s exact requirements. To make them more flexible to configure, routers come in two main parts:

* Chassis the real box and necessary components inside it, like power supply, fans, rear and front faceplates, indicator lights, and slots

* Ports and modules the printed circuit boards that slide into router box
Cisco’s router product-line formation tries to guide you to a product or at least to a logically focused choice of products meeting all five requirement areas in Table.

Getting the correct router for your needs is mainly a three-step process. The following illustrates process of selecting a router for a big branch office operation:

Initially Cisco’s routers are grouped into product families known as series. Selecting a router product series is generally a issue of budget, because every series returns a price or performance tier. Models within series are usually based on same chassis, which is the metal frame and basic parts around which router is built. We will choose Cisco 2000 Series because it fits both buy budget and performance requirements for our large branch office.

Then, we choose Cisco 2650 as it has two Ethernet ports; and our pretend branch office will function two subnets, one for customer service office and other for front office. The two Ethernet ports will allow us separate two departments, thus isolating traffic.