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Conference 7.286::fddi

Title:	FDDI - The Next Generation

Moderator:	NETCAD::STEFANI

Created:	Thu Apr 27 1989
Last Modified:	Thu Jun 05 1997
Last Successful Update:	Fri Jun 06 1997
Number of topics:	2259
Total number of notes:	8590

1557.0. "CERTIFICATION TESTER ON TP-PMD" by EVTAI1::LANGBIEN (Gerard LANGBIEN @EVT) Tue Jan 24 1995 05:02

    Hello,
    
    On some Request For Proposal, customers mentionned that UTP cabling
    system must be certified with dynamics tests.
    
    To day, I can do that in Ethernet environnment by using Tester/Simulator
    (like E 20 from Experdata). These devices work by sending/receiving and
    compare frames between two sets.
    
    Is there something doing the same in FDDI ?.. 
    with TP-PMD interface of course.
    
    Regards 
    
    G.L NIS France

T.R	Title	User	Personal Name	Date	Lines
1557.1	we are looking at them now	NETCAD::MELARAGNI		`Tue Jan 24 1995 12:01`	8
	Yes, there is. Several vendors produce UTP testers that cover Cat 3 and Cat 5 cabling. DECconnect is currently working to qualify vendors' testers for use in the field. Contact Chris (NETCAD::) DiMinico with any questions you have. He is actively working this issue. bill
1557.2	Dynamic not Static	EVTAI1::LANGBIEN	Gerard LANGBIEN NIS/FR	`Wed Jan 25 1995 04:48`	9
	Thanks Bill, Yes I know this kind of tester and I use it. But I qualify as "Static Tester". It doesn't simulate a real traffic... I am looking for "Dynamic Tester" that will able to create a real traffic, with FDDI frame structure, from 1 to 99 % of bandwith. G�rard.
1557.3	i don't get it	NETCAD::MELARAGNI		`Wed Jan 25 1995 07:59`	12
	I don't understand. The very purpose of the static testers is to eliminate the need for dynamic ones. Such testers (if they exist) will be very expensive. There is nothing that a dynamic tester can do that a static tester can't when it comes to checking the cable plant. In fact the dynamic testers will not allow certification of the cable plant. Certification requires the testing of the electrical characteristics of the cable plant and dynamic testers can't do that. Besides that, the testers you call "static" are no such thing. They send out pulses, or sweep through frequencies, in order to exercise the cable at all frequencies of interest. bill
1557.4		NETCAD::B_CRONIN		`Fri Jan 27 1995 10:32`	12
	This is the first time that I've heard of anyone asking for an on site test of this type. I don't know of anyone that offers such a test. Most people run their own tests in this situation, in fact it has been common for people to run their own FDDI test beds before investing in the technology. I don't know what to offer as an alternative, other than suggesting that they get something on loan and try it out for a while to see if they are satisfied.
1557.5	Always Carry a spare Hub900 !! 8-)	MSDOA::REED	John Reed @CBO, (803) 781-9571 NIS Networker	`Tue Jan 31 1995 21:15`	13
	In my opinion, you should use a good CAT 5 media tester (the microtest PentaScan was the last one I used) first, to verify the length and the impedance at desired frequencies, and the pair mappping. Then just assemble a PC with an FDDI TPPMD card, and put it on a push-cart. Attach a DECconcentrator 900mx in the equipment room, and push the PC to some user offices, and boot it up. I did this at my last TPPMD FDDI site, and it worked nicely for me. Use their equipment, and they must agree that you have tested using their real environment. JR
1557.6	Use their Equip, to prove "Reality"	CIVPR1::MARKIS	Depends on Your Perspective, Ofcourse ...	`Tue Feb 13 1996 12:26`	29
	> assemble a PC with an FDDI TPPMD card, and put it on a push-cart. > Attach a DECconcentrator 900mx in the equipment room, and push the PC > to some user offices, and boot it up. > I did this at my last TPPMD FDDI site, and it worked nicely for me. > Use their equipment, and they must agree that you have tested using > their real environment. We did the same thing at a Huge Government Site, that also required going from building to building. We used Norton's Performance Tests (it Writes several hundred packets, then reads several hundred packets). This helped us to show them where the bottlenecks were, which protocols (DECNET, TCP/IP, NETb) worked best and which worked worse. The fact that it was one of their PC's and we were talking to 5 of their Servers, proved everything they had been seeing and were now willing to believe. We also proved that Bell-Atlantic's (local phone company) FNS (10Mb) Shared Service had "NO" Guaranteed "Minimum" Bandwidth. We had consistant speeds as low as 9.6kb. YES, 9600bps ...... However, on a Holiday, we actually got the full 10Mb/s sustained. This proved that they needed to go to something more dedicated (for the $1K/month they paid per drop) Chris 8^)