Installation
16
Table 1: IEEE 802.3 Network Specifications
UTP (RJ45) Connector
A UTP cable with an RJ45 connector is shown in Figure 8. For a 10BASE-
T link between a hub, a repeater, a Medium Attachment Unit (MAU) you
will need a cross cable. For a connection to a Network Interface Controller
(NIC), the cable is wired straight through.
10BASE-T UTP cables can be up to 100 meters (328 ft.) in length. The
cable should be 22 to 26 AWG UTP wire with 100
Ω
impedance. The AT-
TS90TR switch uses RJ45 modular connectors for its 10BASE-T
connections.
10BASE-T Cable. There are various grades of voice-quality and data-
quality cables available. These can appear to be similar externally,
although their high-speed data transmission characteristics are radically
different.
The identification problem is made worse by some suppliers selling voice-
quality cables as data-quality cables.
If any voice-quality cables are used in a 10BASE-T network system, data
movement is slow, collision-prone or non-existent. To confuse the issue, the
Link indicator on the interface will usually indicate a valid link in such a
case.
For the foregoing reasons, it is absolutely vital that all cabling used with
the 10BASE-T connections is be category 3, 4 or 5.
As a rule of thumb, if a cable type is flat, it is typically untwisted and will
cause problems. If a cable is more or less round in cross section, it will
typically work.
10BASE-T
100BASE-TX
Media
Unshielded Twisted Pair
Unshielded Twisted Pair
Topology
Star, Tree
Star, Tree
External Devices
Network Adapter Card
Network Adapter Card
Maximum Segment Length
100 meters 328 feet)
100 meters 328 feet)
Figure 8: RJ45 Connector
