Black Box Explains... Router Basics
Routers are intelligent, high-level devices that enable individual, unique, logical networks to communicate with each other while maintaining their own identities. A router forms the boundary between networks. It connects... more/see it nowlogically separate networks operating under the same transport protocol such as TCP/IP or SNA. Routers are protocol-dependent and must support the protocols being routed. Thanks to the Internet, these protocols have become fairly standardized.
Part of a routers function is to choose a path over which to send packets. This path may involve multiple hops from the source device to a destination that can be across multiple physical networkseven on another continent. In an enterprise-wide WAN divided by routers, each network is managed separately and is assigned a unique network number (OSI Layer 3), usually an IP address.
A router learns the network number of each connected LAN and stores these numbers in a routing table. If a network changes, the router learns and stores the change automatically. The router uses these routing tables combined with a routing algorithm to decide the best way to route a packet. collapse
Black Box Explains... Smart Serial Interface
Smart Serial is the Cisco router interface. It uses a space-saving 26-pin connector that automatically detects RS-232, RS-449, RS-530, X.21, and V.35 interfaces for both DTE and DCE devices based... more/see it nowon the type of cable used.
Smart Serial connectors can be found on Smart Serial cables and on the dual-serial-port WAN interface cards used in Cisco 2600 and 1720 series routers. The cables feature a Smart Serial connector on one end and a standard cable connector (such as DB25 or V.35) on the other end. The Smart Serial connector attaches to the dual-serial-port WAN interface card.
Each port on the WAN interface card features a Smart Serial connector. Ports can be configured independently to support two different physical interfaces. For example, you can run RS-232 cable to one port and RS-449 cable to the other port using a single WAN interface card.
What if you need to replace that RS-232 cable with V.35 cable? Just plug a Smart SerialV.35 cable into the port. Because any Smart Serial connector on the WAN interface card attaches to any Smart Serial cable connector, no additional interface or adapter is necessary. Changing the configuration of your network is literally a snap! collapse