| T.R | Title | User | Personal
Name | Date | Lines |
|---|
| 1406.1 | | koning.lkg.dec.com::koning | Paul Koning, B-16504 | Mon Jul 18 1994 17:35 | 4 |
| Did you REALLY mean single mode and 62.5/125 fiber? That's not valid,
since 62.5/125 is multimode fiber.
paul
|
| 1406.2 | I am checking the fiber type | VAXRIO::CUPOLILLO | | Tue Jul 19 1994 12:08 | 14 |
|
It seens strange to me, too. I received this info from our techinician
at the customer's site. I will check this with the guys that installed the
link and as soon as I get the answer I will put it here.
Meanwhile, I would like to ask some more questions about the loopback
test. I would like to know if it is necessary to disconnect the bridge from
the Ethernet and use a NI loopback at the NI port to run the selftest? Is it
necessary to use the two loopbacks connectors (single and multimode) to run
the test? What will be the leds status of the FI board at the end of the
test?
Cupol
|
| 1406.3 | 62.5/125 is most likely ok to use..... | 4371::BATTERSBY | | Tue Jul 19 1994 13:37 | 10 |
| Well I looked up an old table of fiber types that could be used
on the DEBAM-RF/RG single mode fiber bridges, and 62.5/125 micron
fiber is an allowable fiber type for 1300 nm optics, and suggests
a 17db power budget, 10km distance, and minimum attenuation of 7db.
Again, these numbers I mention are for the DEBAM-RF/RG single mode
fiber interface as an example of a single mode fiber bridge which
uses the 62.5/125 micron fiber (obviously terminated in the proper
connectors normally used for single mode fiber).
Bob
|
| 1406.4 | Multimode only on DEBAM-RF | 4371::PAGLIARO | Rich Pagliaro, Hub Products Group | Tue Jul 19 1994 13:44 | 7 |
| Bob,
The DEBAM-RF didn't use single mode optics. The increased distance was
achieved by using a full-duplex ethernet interface and multi-mode
optics with a greater power budget than that specified for FOIRL.
-Rich
|
| 1406.5 | Corrected, FDDI SM fiber more like 8-10/125 size.... | 4371::BATTERSBY | | Tue Jul 19 1994 14:02 | 7 |
| Yeah...you're right, it's been that long since I looked at that
stuff for DEBAM.
Yup single mode fiber for FDDI is more on the order of 8-10 microns
for a core diameter & a cladding diameter of 125 microns. It's
designed to work at a wavelength of 1300 nm.
Bob
|
| 1406.6 | They used the right fiber | IMTDEV::CUPOLILLO | | Tue Jul 19 1994 18:41 | 19 |
|
Talking with the responsables for the link installation I confirmed that
they used 8-10/125 fiber with FC/PC connectors.
Now, when we connect the two bridges via the optical link, we get the
following status in FI board: FI BAD - OFF, ACT1 - OFF, FWD1 - BLINK, PH1 -
BLINK GREEN, PHY2 - BLINK GREEN. Disconnecting the bridge from the Ethernet
and using an Ethernet loopback and FDDI loopbacks for ports A (single) and
port B (multi) and setting switch 7 to selftest we get: FI BAD - OFF, ACT1 -
ON, FWD1 - OFF, PH1 - ON RED, PH2 - OFF, with these indications what may be
the conclusion about the bridge functionality?
The customer uses DECNET and TCP/IP over the network. Is it necessary
configure any other parameter in the bridge to get it to work?
Excuse me for the silly questions, but this the first time I faced a FDDI
bridge troubleshooting.
Cupol
|
| 1406.7 | Link loss value? | NOTAPC::LEVY | | Wed Jul 27 1994 17:38 | 5 |
| What's the measured loss on the SM link? Must be at least 12dB and less
than 22dB.
With a distance of only ~13km, the loss may be too small without an
attenuator.
|