Olicom CrossFire 8600, Manual To Operations

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CrossFire 8600/8605 Token-Ring Switches v. 1.2, P/N: 710001641 Preparing for Installation
Rules to Remember
This section will help you understand the physical configuration restrictions for the
switch. In brief, you must remember the following rules when planning to install
the switch:
•
18,192 byte maximum physical frame length.
•
For shared-media LAN segments, acceptable distances are defined by the hub
or concentrator attached to the switch port.
•
Straight-through cables for all ports.
•
If you create parallel paths directly between switches, be sure that you have
enabled the spanning tree protcol (see “Spanning Tree for TrBRF Screen” on
page 99). The default setting for the spanning tree protocol is disabled.
•
The spanning tree protocol will not function between different BRFs within
one switch.
The following paragraphs provide greater detail about the physical restrictions.
Frame Length Limit
The switch supports a maximum physical frame length of 18,192 bytes. This
corresponds to a Maximum Transfer Unit (MTU) of 17,800 bytes. The default
maximum physical frame length of the switch is 4,546 bytes which corresponds to
an MTU of 4,472 bytes.
Please read section “Required Network Preparation - Frame Length Limit” on
page 55 before you start the installation. This section contains more detailed
information on the frame length limits.
Cables and Distances between Devices
The CrossFire 8600 supports attachment to 100 ohm and 120 ohm twisted-pair
(UTP or STP), and 150 ohm STP, as defined in the EIA/TIA 568A and ISO/IEC
11801:1995.
On CrossFire 8605, a UTP/STP connection is only supported via the CrossFire
8610 Token-Ring UEM.
The CrossFire 8605 supports 50/125 µm and 62.5/125 µm fiber cables with a
VF-45 connector. Fiber cable lenghts up to 2000 meters are supported.
See Appendix B, “Cable and Pin Information” for specific information on
supported cable types, cable lengths and connector pinouts.