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Chapter 4:
Understanding Network Cabling
Are not limited in the number of nodes in a single logical segment
Use RJ-45 connectors for all connections (this type of connector is similar to
a modular telephone connector, but the RJ-45 is larger)
100Base-T networks are similar to 10Base-T networks and have these characteristics:
Require four actual wires (two twisted pairs in a single sheath)
Must use Cat-5 cable or better
Are limited to a length of 100 meters (328 feet) for each node connection
Are not limited in the number of nodes in a single logical segment
Use RJ-45 connectors for all connections
1000Base-T networks are notable in that they can run over existing Cat-5 cable, but
at ten times the speed of 100Base-T networks. Running over Cat-5 cable is a significant
advantage for 1000Base-T, because over 75 percent of installed network cabling today
10Base-What?
The various Ethernet standards referred to as, for instance, 10Base-2, 10Base-T,
100Base-T, and so on contain in their name all you need to know about what they do.
The first portion--the number--can be 10, 100, or 1000, and this number indicates
the data rate (in Mbps) that the standard carries. The word Base means the network
is baseband rather than broadband. (A baseband connection carries only one signal at
a given instant; a broadband connection carries multiple signals at any time.) The
terminating letter or number indicates what sort of cable is used: T for twisted pair,
2 for thin coaxial, 5 for thick coaxial, and F or X usually indicating fiber-optic cable.
Here's a quick reference guide to the different standards commonly seen:
10Base-2
10 Mbps, coaxial (RG-58) cable
10Base-5
10 Mbps, coaxial (RG-8) cable
10Base-T
10 Mbps, twisted-pair (two pairs, Cat-3 or
higher) cable
100Base-T
100 Mbps, twisted-pair (two pairs, Cat-5) cable; a
variant called 100 Base-T4 designates four pairs
100Base-TX
100 Mbps, twisted-pair (two pairs, Cat-5) cable
100Base-FX
100 Mbps, fiber-optic cable
1000Base-T
1 Gbps, twisted-pair (four pairs, Cat-5) cable
10GBase-X
10 Gbps, fiber-optic cable