IBM 8239 Token-Ring Stackable Hub, Setup And User Manual

Page: 25 / 141

RI/RO Module
This section describes cabling for the RJ-45 RI/RO Module and the Optical Fiber
RI/RO Module.
RJ-45 RI/RO Module
Table 1-2 shows the types of cable and maximum distances supported for the
RJ-45 RI/RO Module.
Table 1-2. RJ-45 RI/RO Module Cabling
Cable Type 4-Mbps Ring Speed 16-Mbps Ring
Speed
UTP, ScTP, or FTP Cat 3 250 m (820 ft) 100 m (328 ft)
UTP, ScTP, or FTP Cat 4 425 m (1394 ft) 210 m (689 ft)
UTP, ScTP, or FTP Cat 5 425 m (1394 ft) 225 m (738 ft)
STP or STP-A 750 m (2460 ft) 375 m (1230 ft)
Optical Fiber RI/RO Module
The recommended maximum fiber length that can be used between Ring In and
Ring Out fiber connections is 2 km (1.2 miles) of 62.5/125-micron multimode optical
fiber cable. This distance applies to both 4-Mbps and 16-Mbps rings. See
IBM
Cabling System Optical Fiber Planning and Installation, GA27–3943, for more
information about optical fiber.
Physical Specifications
This section gives the physical specifications, environmental requirements, and
power requirements of the 8239.
Dimensions
Figure 1-3 on page 1-6 shows the exterior dimensions of the 8239.
Chapter 1. Introduction and Planning
1-5