3com 3CBLSF26H Manual De Usuario
9-1
9
Glossary
Table 9-1 Glossary
Item
Description
10BASE-T
The IEEE specification for 10 Mbps Ethernet over Category 3, 4 or 5
twisted pair cable.
twisted pair cable.
100BASE-TX
The IEEE specification for 100 Mbps Fast Ethernet over Category 5
twisted-pair cable.
twisted-pair cable.
1000BASE-LX
IEEE 802.3z specification for Gigabit Ethernet over 9/125 micron core
single-mode fiber cable.
single-mode fiber cable.
1000BASE-SX
IEEE 802.3z specification for Gigabit Ethernet over two strands of
50/125 or 62.5/125 micron core multimode fiber cable.
50/125 or 62.5/125 micron core multimode fiber cable.
1000BASE-T
IEEE 802.3ab specification for Gigabit Ethernet over 100-ohm Category
5, 5e or 6 twisted-pair cable (using all four wire pairs).
5, 5e or 6 twisted-pair cable (using all four wire pairs).
Auto-negotiation
Auto-negotiation is where two devices sharing a link, automatically
configure to use the best common speed. The order of preference (best
first) is: 1000BASE-T full duplex, 100BASE-TX full duplex, 100BASE-TX
half duplex, 10BASE-T full duplex, and 10BASE-T half duplex.
Auto-negotiation is defined in the IEEE 802.3 standard for Ethernet and
is an operation that takes place in a few milliseconds. Auto-negotiation
must be enabled for the 1000BASE-T ports to operate at 1000 Mbps, full
duplex.
configure to use the best common speed. The order of preference (best
first) is: 1000BASE-T full duplex, 100BASE-TX full duplex, 100BASE-TX
half duplex, 10BASE-T full duplex, and 10BASE-T half duplex.
Auto-negotiation is defined in the IEEE 802.3 standard for Ethernet and
is an operation that takes place in a few milliseconds. Auto-negotiation
must be enabled for the 1000BASE-T ports to operate at 1000 Mbps, full
duplex.
Bandwidth
The information capacity, measured in bits per second, that a channel
can transmit. The bandwidth of Ethernet is 10 Mbps, the bandwidth of
Fast Ethernet is 100 Mbps and Gigabit Ethernet is 1000 Mbps.
can transmit. The bandwidth of Ethernet is 10 Mbps, the bandwidth of
Fast Ethernet is 100 Mbps and Gigabit Ethernet is 1000 Mbps.
BPDU
Bridge Protocol Data Unit. A type of information packet that ensures that
data is efficiently exchanged between switches in a LAN. BPDU
messages detect loops in a network, and remove them by shutting down
the bridge causing the loop.
data is efficiently exchanged between switches in a LAN. BPDU
messages detect loops in a network, and remove them by shutting down
the bridge causing the loop.
Category 3 Cables
One of five grades of Twisted Pair (TP) cabling defined by the
EIA/TIA-568 standard. Category 3 is voice grade cable and can only be
used in Ethernet networks (10BASE-T) to transmit data at speeds of up
to 10 Mbps.
EIA/TIA-568 standard. Category 3 is voice grade cable and can only be
used in Ethernet networks (10BASE-T) to transmit data at speeds of up
to 10 Mbps.
Category 5 Cables
One of five grades of Twisted Pair (TP) cabling defined by the
EIA/TIA-568 standard. Category 5 can be used in Ethernet (10BASE-T)
and Fast Ethernet networks (100BASE-TX) and can transmit data at
speeds of up to 100 Mbps. Category 5 cabling is better to use for
network cabling than Category 3, because it supports both Ethernet (10
Mbps) and Fast Ethernet (100 Mbps) speeds.
EIA/TIA-568 standard. Category 5 can be used in Ethernet (10BASE-T)
and Fast Ethernet networks (100BASE-TX) and can transmit data at
speeds of up to 100 Mbps. Category 5 cabling is better to use for
network cabling than Category 3, because it supports both Ethernet (10
Mbps) and Fast Ethernet (100 Mbps) speeds.
Category 5e Cables
One of five grades of Twisted Pair (TP) cabling defined by the
EIA/TIA-568 standard. Category 5e can be used in Ethernet
(10BASE-T), Fast Ethernet (100BASE-TX) and Gigabit Ethernet
(1000BASE-T) networks, and can transmit data at speeds of up to 1000
Mbps.
EIA/TIA-568 standard. Category 5e can be used in Ethernet
(10BASE-T), Fast Ethernet (100BASE-TX) and Gigabit Ethernet
(1000BASE-T) networks, and can transmit data at speeds of up to 1000
Mbps.