Olicom 8600, 8605 Rules to Remember, Frame Length Limit, Cables and Distances between Devices

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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:

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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.

CrossFire 8600/8605 Token-Ring Switches v. 1.2, P/N: 710001641 Preparing for Installation