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Re: [802.3_DIALOG] Considerations on technical feasibility of 1GE POF and being future proof


You spoke of 20 years ago.  The comparison to 30 years ago is even more striking.

30 years ago was 1984.
While the 802.3 (thick coax) standard had been approved in June of 1984,
the IEEE did not get around to actually getting it published until New Years 1985.

At that point 10BASE-T and even FOIRL were still projects in the future.
The work in 802.3 consisted of
- 10BASE2 (i.e. "CheaperNet" BNC based coax, approved 6/13/85)
- 10BROAD-36 (i.e. Ethernet over Broadband, approved 9/19/85)
- 10 Mb/s Baseband Repeater, approved 3/13/86
The StarLAN task force had been recently formed but was still working on the 5 Criteria.
The FOIRL activity was started at the November '84 meeting.

StarLAN was the first twisted pair activity and it was directed towards the installed base of AT&T DIW wiring (approximately (but not quite) equivalent toCat 3, 4-pair or 25-pair.  We weren't even considering residential cabling at the time which was even lower grade (6-pair unjacketed).

There was no standard for Cat 3 and AT&T wasn't willing to release their proprietary specs for DIW.  802.3 had to characterize DIW on its own.  Cat 5 wasn't even a gleam in anybody's eye at the time.  The biggest media news on the block was the newly released IBM Cabling System Type 1 Cable.  It was spec'd all the way to 16 MHz (even though it was/is a lot better than that)

Your point, I believe and which I support is that alleging to be "future proof" is difficult to do.  I don't think many of us (certainly not a consensus) believed that Cat5 was as "future proof" as it has turned out to be.

Best regards,

Geoff Thompson

On Oct 8, 2014, at 1:01 PMPDT, ROBERT GROW <bobgrow@xxxxxxx> wrote:


I will take issue with your 30 year criteria for home networking.  You certainly are entitled to that opinion, but I believe it unrealistic, and accepting the 30 year criteria forces one to conclude Ethernet is not viable as a home network technology, something both history and market input to our study group argue against. Why do I come to that conclusion?  Let¡¯s just look back 20 years.  

What was the state of Ethernet?  The approved standard included 10BASE-T and p802.3u was working to specify 100BASE-TX and 100BASE-FX.  The media for those:  Cat 5 and primarily 100/140 multimode fiber.  In the last 20 years, 802.3 has moved from Cat 3 for 10BASE-T to Cat 5 for 100BASE-TX, then we needed Cat 5e for 1000BASE-T, Cat 6A for 10GBASE-T (the cable industry¡¯s best guess for a future proof cable before 10GBASE-T was Cat 6), etc.  Similarly, MMF has moved to 62.5/125, then we got higher bandwidth MMF.  

Optics experts might correct me, but the only media in use 20 years ago that we use today for 1 and 10 Gb/s was single mode fiber (I haven¡¯t researched what changed on types of SMF).  But SMF is not friendly for home network use for both technical and ease of installation reasons.

I was a participant on a cabling discussion group decades ago.  I still remember a question that was similar to your requirement.  ¡°I'm building a 22,000 sq. ft. house (2044 sq. m.) and I don¡¯t ever want to have to replace the data cabling.  What should I install?¡±  My answer was conduit with a pull string.  Then I also provided my opinion for the best copper and fiber options at the time, none of which is a preferred medium today.  

Looking at our history with reuse of media as speed increases, my answer from decades ago still has validity.  And guess what.  For markets where POF is being demanded, that is exactly what exist.  Conduit available for POF installation, and if you install SI-POF as has been proposed to the GEPOF SG, you can use it as a pull string if cabling needs to be upgraded to GI-POF or some other non-conductive medium.