FDDI network concentrators are also known as dual-attachment concentrators or DACs and are used on Fiber Distributed Data Interface (FDDI) networks. An FDDI is a wide area network structure that runs on fiber optic lines that can extend up to 124 miles and support thousands of users. It contains two token rings, with one used for backup if the first fails.

FDDI network concentrators attach to the rings to monitor and prevent failed or powered down devices from bringing down the network. FDDI networks are an older technology and parts can be difficult to find. Here are some things to keep in mind when looking for FDDI computer concentrators:

1. Look for refurbished FDDI network concentrators from companies that sell used network equipment.

2. Make sure you can still get support, configuration and troubleshooting information from the manufacturer.

3. Look for well-known manufacturers that provide legacy support and information.

Action Steps
The best contacts and resources to help you get it done

Look to providers of refurbished equipment for an FDDI network concentrators list

FDDI concentrators have been largely replaced with newer technology and are no longer manufactured. You can purchase refurbished concentrators to keep FDDI networks running from online retailers.

I recommend: Contact Timbercon for refurbished concentrators from various manufacturers. Place a special order with TamayaTech for refurbished Bay Networks, IBM, DEC, 3Com and SynOptics concentrators with a 90-day warranty. For parts, check out MTMnet, which carries 3Com parts and concentrator switch module connectors.

Find FDDI network concentrators by SynOptics

SynOptics was one of the earliest and most innovative producers of networking products, including concentrators. The company merged with others to form Bay Networks, which was later acquired by Nortel.

I recommend: Liberteks carries the SynOptics System 2000 Lattisnet FDDI Concentrator. CODE Micro offers a large selection of SynOptics concentrators. Nortel Networks offers user guides and support for legacy SynOptics and Bay Networks FDDI concentrator models.

Get FDDI computer concentrators manufactured by 3Com

3Com was another early provider of FDDI concentrators. The company has been a provider of solutions since the early days of networking.

I recommend: Find 3Com concentrators at online retailers like CODE Micro, Ciao and 9to5computer. Get FDDI network concentrators information and support from 3Com.

Tips & Tactics

Helpful advice for making the most of this Guide

• •  Find out about warranty and return options before purchasing from an FDDI network concentrators provider online. The company may offer a short warranty period or no warranty at all. Also inquire about the requirements for returning the unit if it doesn't function. You may be liable for the cost of shipping as well as a restocking fee.
• •  When purchasing fiber cable for FDDI network concentrators, you may be able to get significant savings by buying in bulk.
• •  As parts become more difficult to find, consider replacing your FDDI computer concentrators and other equipment with newer technology. A network consultant can help you determine your needs and set a budget.