Eia/Tia-232 Connections; Eia/Tia-449 Connections - Cisco CISCO2515-RF - 2515 Router User Manual

Preparing to Connect to a Network

EIA/TIA-232 Connections

The EIA/TIA-232 standard supports unbalanced circuits at signal speeds up to 64 kbps.
The serial port (labeled "SERIAL") supports synchronous connections. The console and
auxiliary ports also use an EIA/TIA-232 connection; however, the console and auxiliary
ports support asynchronous connections.
The network end of the EIA/TIA-232 serial transition cable (not included) provides a
DB-25 connector, as shown in Figure 2-2. The end that connects to the serial port on the
rear panel of the router has a DB-60 connector. EIA/TIA-232 serial transition cables are
available with a DB-25 plug or receptacle in either DTE or DCE mode. To order a cable,
refer to the section "Obtaining Service and Support" in the "Overview of the Router"
chapter.
Figure 2-2

EIA/TIA-449 Connections

The EIA/TIA-449 standard, which supports balanced and unbalanced transmissions, is a
faster (up to 2 Mbps) version of the EIA/TIA-232 standard that provides more functions
and supports transmissions over greater distances.
The EIA/TIA-449 standard was intended to replace the EIA/TIA-232 standard, but it was
not widely adopted primarily because of the large installed base of DB-25 hardware and
because of the larger size of the 37-pin EIA/TIA-449 connectors, which limited the number
of connections possible (fewer than possible with the smaller, 25-pin EIA/TIA-232
connector).
2-12 Router Installation and Configuration Guide
EIA/TIA-232 Serial Transition Cable Connectors, Network End
DTE
DCE