AT-1720
22
The identification problem is exaggerated by the fact that some
suppliers have sold purportedly data-quality cables
manufactured with voice-quality cabling.
If any voice-quality cabling is used in a 10BASE-T network
segment, 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 adapter card connections is of level 3, 4,
5 or IBM type 1. 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 section, it will typically work.
The six common modular cable specifications and their
applicability to 10BASE-T network use are shown in Table 4,
and cable schematics are shown in Figure 2.