Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

  • Congratulations strongm on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!

10base5 transceiver question

Status
Not open for further replies.

nojo

MIS
Mar 7, 2002
1
US
I just walked into a job where the customer has a 10base5 backbone, UGH!, with each vampire-tap tranceiver feeding 10base2 to 10 PCs(daisy chained). he wants to add more PCs on each segment. Here's the question: how many PCs can the transceiver handle, will I need a repeater to boost the signal?
 
10base-5: The max. segment length (i.e. without a repeater) is 500 meters. Technically speaking you can have as many computers as you like as long as the segment length does not exceed the 500 meters. <br>

10base-2: Max segment length is 185 meters without a repeater. <br>

Both networks are daisy chained along a terminated bus topology.

In my opinion, I would set a new subnet for the new computers and eventually move away from the 50-Ohm or the thin co-axial cables... Fiber or UTP networks are much easier to trouble-shoot also are much faster 10Mbps vs. 100Mbps or better!!!

ArvSar
 
Wow... someone still uses thick and thin ethernet. I agree with Sararv...... You should plan to update you network cabling. However, the powers to be in your organization probably figure that if it is doing the job..... Why replace it. So, I will try to answere some of your questions.

10BASE-5: Thick Ethernet. No more than 100 taps per 500 meter segment of cable. Transceivers must be spaced at least 2.5 meters apart, (The black rings on the 10BASE-5 cable are spaced at 2.5 meters). 10BASE-5 cable cannot exceed 500 meters without repeaters. No more than five 500 meter segments allowed in the network.

10BASE-2: Thin Ethernet. No more than 30 devices should be placed on any thin ethernet segment. (Equipment manufacturers may allow less devices per segment. I believe DEC supports only 8 or 10 devices per segment.) Devices should be spaced at least .5 meter (cable distance) apart. Seach thin ethernet segment can be up to 185 meters.

Both thick and thin ethernet segments must have 50 ohm terminators at each end of the segment. One end of each segment should be grounded. If you follow the rules above - You could have up to 3000 devices per 10BASE-5 segment. But...... The performance will be terrible. Keep in mind that any device that you put on any segment in this configuration will be competing for bandwidth with every other device on every segment on the network. Every device that you add will tend to slow the entire network down. And any malfunctioning device on any segment can flood the network with packets that will bring the system to a crawl. Also keep in mind that this topology will only support 10mb ethernet.

One last thing. 10BASE-5 and 10BASE-2 are not longer supported by standards commitees such as EIA/TIA. Therefore, manufacturers of 10BASE-5 and 10BASE-2 devices will probably phase out any product lines associated with these topologies. Making it difficult to find spare / replacement parts in the future.

Keith
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor

Back
Top