3Com 3 manual Fiber Cables, Cross-over Cable Straight-through Cable

28CHAPTER 2: INSTALLING THE SWITCH

port, you need a cross-overcable. Many ports on workstations and servers are configured as MDI (straight-through). If you want to make a connection to an MDI port, you need to use a standard straight-throughcable. See Table 7.

3Com recommends that you use Category 5 twisted pair cable — the maximum segment length for this type of cable is 100 m (328 ft).

CAUTION: If you want to install the Switch using a Category 5E or Category 6 cable, 3Com recommends that you briefly connect the cable to a grounded port before connecting network equipment. If you do not, the cables Electrostatic Discharge (ESD) may damage the Switch's port.

You can create a grounded port by connecting all wires at one end of a UTP cable to an earth ground point, and the other end to a female RJ-45 connector located, for example, on a Switch rack or patch panel. The RJ-45 connector is now a grounded port.

Table 7 Cables required to connect the Switch 4200 Family to other devices if auto-negotiation is disabled

Cross-over Cable Straight-through Cable

Switch to Switch (MDIX to MDIX)

Switch to Hub (MDIX to MDIX)

Switch to PC (NIC) (MDIX to MDI)

✓ ✕

✓ ✕

✕✓

Choosing the Correct Choose from the following cable options:

Fiber Cables

■The 1000BASE-SX SFP ports can be connected to multimode fiber cables only.

■The 1000BASE-LX and LH70 SFP ports can be connected to single-mode fiber cables. The 1000BASE-LX SFP ports can also be connected to multimode fiber cables using a conditioned launch cable.

For detailed information on fiber cable specifications, refer to the SuperStack 3 Implementation Guide that accompanies your Switch.