Specifications

10 Second-Generation Fast Ethernet Interface Processor (FEIP2) Installation and Configuration
Installation Prerequisites
IEEE 802.3u specifies the following different physical layers for 100BASE-T:
• 100BASE-TX—100BASE-T, half and full duplex over Category 5 unshielded twisted-pair
(UTP), Electronics Industry Association/Telecommunications Industry Association
[EIA/TIA]–568-compliant cable
• 100BASE-FX—100BASE-T, half and full duplex over optical fiber
• 100BASE-T4—100BASE-T, half and full duplex over Category 3, 4, or 5 UTP or shielded
twisted-pair (STP) cabling with four pairs; also called 4T+ or T2, which is 2-pair UTP over
Category 3 cable.
Each physical layer protocol has a name that summarizes its characteristics in the format
speed/signaling method/segment length, where speed is the LAN speed in megabits per second
(Mbps), signaling method is the signaling method used (either baseband or broadband), and segment
length is typically the maximum length between stations in hundreds of meters. Therefore,
100BASE-T specifies a 100-Mbps, baseband LAN with maximum network segments of 100 meters
(or 400 meters for 100BASE-FX).
IEEE 802.3u 100BASE-T Specifications
Table 2 lists the cabling specifications for 100-Mbps Fast Ethernet transmission over UTP, STP, and
fiber-optic cables. Table 3 summarizes IEEE 802.3u 100BASE-T physical characteristics for
100BASE-TX and 100BASE-FX.
Table 2 Specifications and Connection Limits for 100-Mbps Transmission
Table 3 IEEE 802.3u Physical Characteristics
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. Both 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 FE interface and the appropriate transceiver.
5. This length is specifically between any two stations on a repeated segment.
1. DTE = data terminal equipment.
Parameter RJ-45 MII SC-Type
Cable specification Category 5
1
UTP
2
, 22 to 24 AWG
3
Category 3, 4, or 5, 150-ohm UTP or STP,
or multimode optical fiber
62.5/125 multimode optical
fiber
Maximum cable length – 1.64 ft (0.5 m) (MII-to-MII cable
4
)–
Maximum segment length 328 ft (100 m) for 100BASE-TX 3.28 ft (1 m)
5
or 1,312 ft (400 m) for
100BASE-FX
328 ft (100 m)
Maximum network length 656 ft (200 m)
5
(with 1 repeater) – 656 ft (200 m)
5
(with 1
repeater)
Parameter 100BASE-FX 100BASE-TX
Data rate (Mbps) 100 100
Signaling method Baseband Baseband
Maximum segment length (meters) 100 m between repeaters 100 m between DTE
1
and repeaters
Media SC-type: dual simplex or single duplex for Rx and Tx RJ-45MII
Topology Star/hub Star/hub