The Cisco 837 router is asymmetric digital subscriber line (ADSL)-over-plain old telephone service (POTS) routing device. It has an integrated 4-port Ethernet switch for the LAN and an ADSL physical interface for the WAN, allowing the router to connect a corporate telecommuter or small office to corporate LANs and the Internet.
The router support high-speed encryption, the 10/100BASE-T switch, and dial backup functionality via the auxiliary console port. The autosensing function in the router eliminates the need for a crossover cable and allows the router to detect medium dependent interface in normal mode (MDI) or medium dependent interface in crossover mode (MDIX) in any other PC or hub with a straight-through cable or a crossover cable. The router is capable of bridging and multiprotocol routing between LAN and WAN ports.