Anyone in UK/EU have any FDDI cables spare?

HP/DEC/Compaq workstations/servers and operating systems (HP-UX, Tru64, OpenVMS, NonStop, etc.)
Forum rules
Any posts concerning pirated software or offering to buy/sell/trade commercial software are subject to removal.
User avatar
urbancamo
Posts: 186
Joined: Thu Jan 13, 2011 1:33 pm
Location: Windermere, UK
Contact:

Anyone in UK/EU have any FDDI cables spare?

Unread postby urbancamo » Sun Oct 27, 2013 10:55 am

I'm after a few FDDI cables to hook up some DEC boxes using FDDI optical cards.
The connectors look like this:

Image

Many thanks, Mark.
Image, VAXstation 4000/90 x2, VAXstation 4000/VLC x2, AlphaServer 1000A, DEC AXP 3000/600 (desktop), DEC AXP 3000/600 x2 (rackmount), DEC AXP 3000/800 (rackmount), AlphaServer 300 4/266, Sun Ultra 5, LA75, PP404, Juki 6100, Brother HR10

User avatar
jan-jaap
Donor
Donor
Posts: 4882
Joined: Thu Jun 17, 2004 11:35 am
Location: Wijchen, The Netherlands
Contact:

Re: Anyone in UK/EU have any FDDI cables spare?

Unread postby jan-jaap » Sun Oct 27, 2013 1:22 pm

Those are SC connectors. What you're looking for is 62.5/125um multimode fibre with SC-SC connectors. 50/125um should work as well, at least for typical lengths. As a rule of thumb, multimode fibre is orange, yellow is single mode.

eBay is your friend... search for 'sc-sc fibre'
:PI: :Indigo: :Indigo: :Indy: :Indy: :Indy: :Indigo2: :Indigo2: :Indigo2IMP: :Octane: :Octane2: :O2: :O2+: Image :Fuel: :Tezro: :4D70G: :Skywriter: :PWRSeries: :Crimson: :ChallengeL: :Onyx: :O200: :Onyx2: :O3x02L:
To accentuate the special identity of the IRIS 4D/70, Silicon Graphics' designers selected a new color palette. The machine's coating blends dark grey, raspberry and beige colors into a pleasing harmony. (IRIS 4D/70 Superworkstation Technical Report)

User avatar
urbancamo
Posts: 186
Joined: Thu Jan 13, 2011 1:33 pm
Location: Windermere, UK
Contact:

Re: Anyone in UK/EU have any FDDI cables spare?

Unread postby urbancamo » Sun Oct 27, 2013 2:26 pm

Thanks very much for the help. I ended up looking in the HP manual for the card and decided that my original eBay search wasn't bringing much back because of the inclusion of the word 'FDDI'. I can see several options now for purchases in the UK at reasonable prices.

Cheers, Mark
Image, VAXstation 4000/90 x2, VAXstation 4000/VLC x2, AlphaServer 1000A, DEC AXP 3000/600 (desktop), DEC AXP 3000/600 x2 (rackmount), DEC AXP 3000/800 (rackmount), AlphaServer 300 4/266, Sun Ultra 5, LA75, PP404, Juki 6100, Brother HR10

User avatar
jan-jaap
Donor
Donor
Posts: 4882
Joined: Thu Jun 17, 2004 11:35 am
Location: Wijchen, The Netherlands
Contact:

Re: Anyone in UK/EU have any FDDI cables spare?

Unread postby jan-jaap » Mon Oct 28, 2013 1:08 am

These fibre cables were also used for 1st gen fibre channel. If you search for FDDI cables you will mostly find cables with MIC connectors (the big ones).

You want to build an FDDI ring? Downside of a ring is that all systems (or at least N-1) must be up, otherwise the ring will collapse. A star topology (like ethernet) is possible if you use a concentrator (the FDDI equivalent of an ethernet switch). I can recommend the Cisco WS-C1400.

Most concentrators use MIC connectors though, so you need SC-MIC cables.
:PI: :Indigo: :Indigo: :Indy: :Indy: :Indy: :Indigo2: :Indigo2: :Indigo2IMP: :Octane: :Octane2: :O2: :O2+: Image :Fuel: :Tezro: :4D70G: :Skywriter: :PWRSeries: :Crimson: :ChallengeL: :Onyx: :O200: :Onyx2: :O3x02L:
To accentuate the special identity of the IRIS 4D/70, Silicon Graphics' designers selected a new color palette. The machine's coating blends dark grey, raspberry and beige colors into a pleasing harmony. (IRIS 4D/70 Superworkstation Technical Report)

robespierre
Posts: 1555
Joined: Mon Sep 12, 2011 2:28 pm
Location: Boston

Re: Anyone in UK/EU have any FDDI cables spare?

Unread postby robespierre » Mon Oct 28, 2013 2:40 am

Well, the ring won't collapse if the down stations have an optical bypass switch. That's what the copper connector on the OP's interface is for. You can only have a ring among DAS interfaces, that's the main disadvantage. SAS interfaces are either point-to-point or use concentrators.

FDDI concentrators are more along the lines of a hub because all the links carry the same shared 100Mbps bandwidth. There were some FDDI switches later on, but I think the DEC GigaSwitch was the only one sold commercially.
:PI: :O2: :Indigo2IMP: :Indigo2IMP:

User avatar
urbancamo
Posts: 186
Joined: Thu Jan 13, 2011 1:33 pm
Location: Windermere, UK
Contact:

Re: Anyone in UK/EU have any FDDI cables spare?

Unread postby urbancamo » Mon Oct 28, 2013 4:28 am

Can you tell me more about how the RJ45 connector is used on these cards? I'd like to avoid having to buy a hub when I'll probably only connect three or four machines maximum.

Thanks, Mark.
Image, VAXstation 4000/90 x2, VAXstation 4000/VLC x2, AlphaServer 1000A, DEC AXP 3000/600 (desktop), DEC AXP 3000/600 x2 (rackmount), DEC AXP 3000/800 (rackmount), AlphaServer 300 4/266, Sun Ultra 5, LA75, PP404, Juki 6100, Brother HR10

User avatar
jan-jaap
Donor
Donor
Posts: 4882
Joined: Thu Jun 17, 2004 11:35 am
Location: Wijchen, The Netherlands
Contact:

Re: Anyone in UK/EU have any FDDI cables spare?

Unread postby jan-jaap » Mon Oct 28, 2013 5:32 am

robespierre wrote:Well, the ring won't collapse if the down stations have an optical bypass switch. [...] FDDI concentrators are more along the lines of a hub because all the links carry the same shared 100Mbps bandwidth.

All true. Token ring would have been a better analogy. I was just trying to 'dumb down' the story such that someone who has only ever seen ethernet as a transport layer would get a picture.
urbancamo wrote:Can you tell me more about how the RJ45 connector is used on these cards? I'd like to avoid having to buy a hub when I'll probably only connect three or four machines maximum.

The optical bypass works like a relay, controlled by the RJ45 (or, more often, some sort of DIN) port. They are rare these days, it would take a long time to acquire any significant amount of them. A concentrator would almost certainly be cheaper in the end.

I think the best introduction to FDDI was hosted on siliconsamsara.org, but it's gone and archive.org doesn't have it. I have a copy here: http://www.jurassic.nl/mirrors/silicons ... /PracFDDI/

Maybe you want to route between your FDDI network segment and your ethernet LAN. In my case, my FDDI equipped SGIs mostly have only 10mbit ethernet, so I use a Linux PC with a PCI FDDI card to do this. Works fine.
:PI: :Indigo: :Indigo: :Indy: :Indy: :Indy: :Indigo2: :Indigo2: :Indigo2IMP: :Octane: :Octane2: :O2: :O2+: Image :Fuel: :Tezro: :4D70G: :Skywriter: :PWRSeries: :Crimson: :ChallengeL: :Onyx: :O200: :Onyx2: :O3x02L:
To accentuate the special identity of the IRIS 4D/70, Silicon Graphics' designers selected a new color palette. The machine's coating blends dark grey, raspberry and beige colors into a pleasing harmony. (IRIS 4D/70 Superworkstation Technical Report)

robespierre
Posts: 1555
Joined: Mon Sep 12, 2011 2:28 pm
Location: Boston

Re: Anyone in UK/EU have any FDDI cables spare?

Unread postby robespierre » Mon Oct 28, 2013 7:49 pm

Here's a nice graphic from Cisco that shows how an optical bypass works:

Image

Without power, the solenoids are in the normal position, linking the A and B cables with mirrors. When the machine is ready it turns on power to the bypass (most of them just have +12V and ground) and the mirrors move to connect the FDDI interface to the ring. None of the other stations on the ring need to detect this change, so the ring isn't disrupted by the machine going up or down.

When an interface on the ring goes down without a bypass, its links to the stations to both sides in the ring go unresponsive. Those stations eventually detect that something is wrong and enter a "ring-wrap" state (one enters "wrap-a" and the other "wrap-b"), after data is disrupted on the ring for several seconds. If multiple interfaces go down, there are two cases: either the down interfaces are contiguous, or not. If they are contiguous, then the ring wraps as before. If not, the operating stations are no longer all able to communicate (some are isolated), disrupting service until the problem is fixed.

This explains why the expensive optical bypass switches were usually only used for critical infrastructure. FDDI was used for some high-speed LANs, but the main attraction was campus- or city-wide networks, so-called MANs or Metropolitan Area Networks. The links of the ring could be single-mode, allowing distances of 10km from each machine to the next, being large routers or servers. Computers within a department would either be on 10Mbit Ethernet or IBM Token Ring, attached to switches that were also part of the FDDI network; or they would be FDDI attached to concentrators, which perform bypassing electronically and do not need optics to do it.
:PI: :O2: :Indigo2IMP: :Indigo2IMP:


Return to “HP/DEC/Compaq”

Who is online

Users browsing this forum: No registered users and 1 guest