Cisco Systems GRP-B manual Ethernet Interface Cable Connection Procedure, RJ-45

Replacing a GRP

Table 6 lists the cabling specifications for 100-Mbps transmission over unshielded twisted-pair (UTP) and shielded twisted-pair (STP) cables.

Note At the auto-sensed data transmission rate of 100 Mbps, the Ethernet port provides maximum usable bandwidth that is less than 100 Mbps; a maximum usable bandwidth of approximately 20 Mbps can be expected if you use either the MII or RJ-45 connection. Transmission speed is determined by the network to which the Ethernet interface is connected and is not user configurable.

Table 6	Specifications and Connection Limits for 100-Mbps Transmission
Parameter		RJ-45	MII
Cable specification		Category 51 UTP2, 22 to 24	Category 3, 4, or 5, 150-ohm UTP or STP,
		AWG3	or multimode optical fiber
Cable length (max)		—	1.64 ft (0.5 m) (MII-to-MII cable4)
Segment length (max)		328 feet (100 m) for	3.28 ft (1 m)5 or 1312 ft (400 m)
		100BASE-TX	for 100BASE-FX
Network length (max		656 feet (200 m)5 (with 1	—
		repeater)

1.EIA/TIA-568 or EIA-TIA-568 TSB-36-compliant.

2.Cisco Systems does not supply Category 5 UTP RJ-45 or 150-ohm STP MII cables or MII transceivers; these items are available commercially.

3.AWG = American Wire Gauge. This gauge is specified by the EIA/TIA-568 standard.

4.This is the cable between the MII port on the GRP and the appropriate transceiver.

5.This length is specifically between any two stations on a repeated segment.

Table 7 lists IEEE 802.3u physical characteristics for 100BASE-TX.

Table 7	IEEE 802.3u Physical Characteristics
Parameter		100BASE-TX
Data rate (Mbps)		100
Signaling method		Baseband
Maximum segment length		100 m between DTE1 and repeaters
Media		Category 5 UTP (for RJ-45) or MII
Topology		Star/Hub

1. DTE = data terminal equipment.

Ethernet Interface Cable Connection Procedure

The RJ-45 and MII receptacles on the GRP represent two physical connection options for one Ethernet interface; therefore, you can use either the RJ-45 connection or the MII connection, but not both simultaneously. RJ-45 and MII cables are not available from Cisco Systems; they are available from outside commercial cable vendors.

Use the following procedure to connect cables to the GRP’s Ethernet interface:

Connecting to the Ethernet Port

22 78-4339-09