You need to understand your existing network infrastructure to determine how well it can meet the needs of your deployment goals. By examining your existing infrastructure, you identify if you need to upgrade existing network components or purchase new network components. You should build up a complete map of the existing network by covering these areas: 1. Physical communication links, such as cable length, grade, and so forth 2. Communication links, such as analog, ISDN, VPN, T3, and so forth, and available bandwidth and latency between sites 3. Server information, including: o Host names o IP addresses o Domain Name System (DNS) server for domain membership 4. Locations of devices on your network, including: o Hubs o Switches o Modems o Routers