Specifications

Preparing to Install the Router 2-15
Preparing to Connect to a Network
EIA-530 Connections
The EIA-530 standard, which supports balanced transmission, provides the increased
functionality, speed, and distance of EIA/TIA-449 on the smaller, DB-25 connector used
for EIA/TIA-232, instead of the 37-pin connector used for EIA/TIA-449. Like
EIA-TIA-449, EIA-530 refers to the electrical specifications of EIA/TIA-422 and
EIA/TIA-423. Although the specification recommends a maximum speed of 2 Mbps,
EIA-530 is used successfully at 4 Mbps or faster speeds over short distances.
The EIA-530 serial transition cable (not included) is available in DTE mode only. The
network end of the EIA-530 adapter cable is a standard DB-25 plug commonly used for
EIA/TIA-232 connections, as shown in Figure 2-6. The end that connects to the serial port
on the rear panel of the router has a DB-60 connector. To order a cable, see the section
“Obtaining Service and Support” in the “Overview of the Router” chapter.
Figure 2-6 EIA-530 Serial Transition Cable Connector, Network End
Asynchronous/Synchronous Serial Connections
The asynchronous/synchronous serial ports use the asynchronous/synchronous 60-pin
connectors located on the rear panel. The lower ports are labeled SERIAL 2 (A/S) and
SERIAL 3 (A/S): the upper ports (depending on which chassis you have) are labeled
SERIAL 4 (A/S) through SERIAL 9 (A/S).
You must use a special serial cable to connect a multiport serial router to a modem or
CSU/DSU. The cable uses a DB-60 connector on the chassis end. See the appendix “Cable
Specifications” for cable pinouts. To order a cable, see the section “Obtaining Service and
Support” in the “Overview of the Router” chapter.
DTE
H1615a