Sfp Modules - Cisco WS-C2940-8TT-S Hardware Installation Manual

Chapter 1 Overview

SFP Modules

The Catalyst 2940-8TF-S switch uses a field-replaceable SFP module to establish Gigabit connections.
You insert an SFP module into the SFP module slot on the front of the switch.
The Cisco SFP modules that are supported by the Catalyst 2940-8TF-S switch include:
•
•
•
•
Note The Catalyst 2940-8TF-S switch only supports 1000 Mbps and full-duplex modes on SFP modules.
The 1000BASE-LX and 1000BASE-SX SFP modules are used to establish fiber-optic connections. You
use fiber-optic cables with LC connectors to connect to an SFP module. The SFP modules support 850
to 1550 nm nominal wavelengths. These field-replaceable modules provide the uplink optical interfaces,
laser send (TX), and laser receive (RX).
The restrictions are that each port must match the wave-length specifications on the other end of the
cable, and the cable must not exceed the stipulated cable length for reliable communications.
lists these stipulations.
Table 1-3 Cabling Stipulations for Fiber-Optic SFP Modules
62.5/125 micron
SFP Multimode
1
Module 850 nm Fiber
2
SX 275 m at
200 Mhz-km
LX —
3
CWDM 1470, 1490, 1510,
1530, 1550, 1570,
1590, 1610
1. nm = nanometer
2. m = meter
3. CWDM = Coarse Wavelength-Division Multiplexing
The 1000BASE-T SFP module is used to establish a Gigabit Ethernet connection through a Category 5
(copper) cable. This module can provide a Gigabit Ethernet connection of up to 100 meters through a
Category 5 cable.
Use only Cisco SFP modules on the Catalyst 2940-8TF-S switch. Each SFP module has an internal serial
EEPROM that is encoded with security information. This encoding provides a way for Cisco to identify
and validate that the SFP module meets the requirements for the switch.
OL-6157-01
1000BASE-LX, fiber-optic
1000BASE-SX, fiber-optic
1000BASE-T, copper
Coarse Wavelength-Division Multiplexing (CDWM), fiber-optic
50/125 micron 62.5/125 micron
Multimode Multimode
850 nm Fiber 1310 nm Fiber
550 m at
500 Mhz-km
— 550 m at
500 Mhz-km
SMF 9/125
50/125 micron 9/125 micron
Multimode Single-mode
1310 nm Fiber 1310 nm Fiber
550 m at 10 km
400 Mhz-km
— 62 miles (100
km)
Catalyst 2940 Switch Hardware Installation Guide
Front-Panel Description
Table 1-3
8 micron
Single-mode
Dispersion
Shifted Fiber
—
—
1470, 1490,
1510, 1530,
1550, 1570,
1590, 1610
1-5