| T.R | Title | User | Personal
Name | Date | Lines |
|---|
| 70.1 | plastic fibre | HAMPS::WILKINS_N | | Mon Jun 04 1990 04:55 | 10 |
| I thought in the U.K plastic fibre was going it. It used to be the
old 200 micron fibre. It is more expensive to purchase than 50/125
and has limited bandwidth, I believe the usefull life is about 5
years.
No it cannot be blown, blown fibre is limited to 50/125, 62.5/125
and 85/125
Neil
|
| 70.2 | DFON and plastic and/or blown fiber | USRCV1::ADAIRC | Claude Adair 252-7087 @RCO | Wed Jun 06 1990 17:12 | 6 |
| Does anybody know if the same folks who put together the DFON
documentation and/or the Media Specifications Reference Guide are
testing plastic fiber? Are appropriate technical resources assigned
to evaluating blown fiber?
How about an "official" status from somebody?
|
| 70.3 | plastic at high speed | LEVERS::J_HILL | | Thu Jun 14 1990 20:00 | 25 |
| Hi, I am not a member of the DEFON comittee. I couldn't
resist to try to help and offer my two cents, though.
Standard FDDI calls for 1300nm optics, this is a problem as most
plastic fiber has extremely large loss at that wavelength, limiting
range to a few meters.
If shorter wavelength optics are used then the link budget
can be made to be more reasonable. An advantage is that 850nm
optics are cheaper, a problem is that its non standard. Somebody
mentioned an 850nm version of the PMD, but probably calls for glass fiber.
If you'r serious, contact the ANSI stanadards commitee and see what
they are up to.
The next problem is that plastic fiber only comes in
step index variety, this alone reduces the bandwidth of the
fiber by an incredible ammount. Since the FDDI baud rate is
125 meg baud, this seriosly limits the length of your link.
I wouldn't venture to guess how far you could go, but don't think
about getting excited.
I can't say that using plastic fiber is impossible, because
it isn't, but such a link would be serioulsy limited in length
and use. The ease of termination is a good selling point though,
but it would be interesting to find out what percentage of an installed
link's price is made up by the termination of fiber.
Finally, I have no idea what DIGITAL has in mind for plastic
fiber.
Jonathan
|
| 70.4 | DO NOT CONTACT THE ANSI COMMITTEE DIRECTLY! | KONING::KONING | NI1D @FN42eq | Fri Jun 15 1990 13:20 | 12 |
| Please DO NOT contact the ANSI FDDI committee.
We have people representing Digital at that committee. Contact those
people if you have ANSI related questions. The last thing we need is for
DEC to appear not to know what it's doing by random letters flying into
ANSI from random places in DEC. (There has been at least one such instance
already and I DON'T want to see another!)
Incidentally, I'm one of the ANSI reps, though on this issue I have no
information to offer. The comments in .2 sound believable.
paul
|
| 70.5 | corrected | LEVERS::J_HILL | | Mon Jun 18 1990 12:04 | 8 |
| Hello,
I appolagize, as Mr. Koning indicates in note 70.4, it is
not a good idea to contact ANSI directly, rather if you have any
questions regarding ANSI topics, please contact a DEC ANSI
representative.
By directing questions to such people, DEC's position will
not be misrepresented.
Jonathan
|
| 70.6 | 6 year update :) | ODIF11::LICATA | | Wed Jan 03 1996 10:53 | 6 |
| A few years have passed. Could I ask
for a brief update on this topic ?
thanks,
Jim
|