[Asterisk-Users] [OT] Old Building Needs a New Telephone System

[John Breeden]

Cat3 - which used to be called "D Inside Wire" (DIW) *is* the wire 
spec'd in the 10baseT IEEE standard. The existing wire plant is 
currently to the 10baseT standard., at least as far as the wire goes. 
(It was originally invisioned that 10bt and analog/digital voice would 
be running in the same 4 pair cable)

Also, the 10bt standard states that 100 meter runs are "typical" using 
DIW. There really is no distance standard with 10baseT, only that it 
"typically" will run 100m using DIW.

PG&E, back in the late 80's had a working 10bt run at The Geysers in 
California of over 500 feet using DIW (AT&T Starlan hubs w/ receive 
threashold set below the standard, BER was still within spec).

That being the case, will DIW support 100baseT? The answer is sometimes 
it will, sometimes it won't. I've seen 200 foot runs of DIW running 
100baseT and BER is within spec.

The bottom line is you might think of *testing* if baseband ethernet 
(10, 1000, whatever) will run using the existing wireplant before 
attempting some dsl/dsl like technology. It would be the least expensive 
route

BTW: Tut make a great product. You might also look at Patton's Ethernet 
Extenders, another dsl like product that's cheap

-JB
Hawaii

Joe Greco wrote:

>>So how can I do this?  Can I use RS485 adapters to get ethernet to each 
>>office via the two pair?  What kind of data rate can I get with RS485, 
>>and would it be half- or full-duplex?  Would wireless work in a steel 
>>building? Is there some other technology that can be used?
>>    
>>
>
>What's all this about RS485?  10/100 Ethernet is two pair (unless you get
>something stupid like 100VG).  You probably can't get the 100 on any 
>reasonable run of Cat3, but by all means, run 10.  We've done it in the 
>past over fairly long distances, thanks to full duplex you need not worry
>about the collision domain issues.
>
>Wireless might be an option but it's also a security nightmare.
>
>... JG
>  
>