Asynchronous or Analog Connections

Standard telephone service typically terminates with an RJ-11 interface, which connects the
modem to the telephone company’s jack. External modems are attached to a Cisco router with
an RS-232 cable. This is also referred to as an EIA/TIA-232 cable. The router end of this connection
uses the Cisco DB-60 connector, a 60-pin termination specific to Cisco routers, and a
DB-25 connector, which interfaces to the modem. The DB-25 connector is quite common in
telecommunications equipment.