Extending Ethernet Basics

Originally Posted by hikaru on Austech.com
Iknw this is not a security question but most people here are lcensed to cablers so i thought i might ask here.
Ok i have 2 offices located in the same building.
They both have a 20 pair cable running from the mdf to the idf in each unit. (i,e the share the ame mdf)
I wanto to take 8 pairs and patch it so i get 2 rj45 ports baically coming out of each idf.. connected directly to each other.
Firstly is this legal,
Second i’m not sure on the quality of the 20 pair so would the network rj45 be ok for running a lan over .. 100mb or 1gb?
Lastly if anyone here is in brisbane and it’s legal how much would i expect to pay to get it done?
p0s the reason i’m want to do this is i dont want to stuff around with cabling outside as i would need body corrporate approval and i jut seems too hard__________________OPTUS CABLE + EASYNEWS + DAP = 700KB/s = DEAD QUOTA
1) You can utilize existing copper cabling anywhere as long as you a) Own the cabling b) Cable owner authorizes you to do so, or c) The cabling is inside a building and a or b apply. Telco’s and carries alike are not allowed to own in-building cabling once it is past the terminating (Demarc) Demarcation MPOE (Main point of entry)
You can research the details of this based on the Australian Telecommunications Act of 1997 and revised 2002. * Note you building may perfer a licensed cable installer, however it is not required by law.
2)You have 2 main issues to worry about if you exceed 100 meters between endpoint of the Ethernet segment:
a) Ethernet packet delayb) Ethernet signal attenuation & crosstalk
These can be solved depending on you distance. Typically setting your link speed to a fixed 10MB and Full Duplex will drive an Ethernet signal further. The quality of the copper and noise on the line also is a factor. The delay issue has to do with the guard interval between Ethernet frames and the collision detection mechanism. The Ethernet standard for cabling requires 8 wires.Twisted pair cabling vs straight telephone wiring is a big difference. All Ethernet rated cabling is twisted pair and today usually CAT5e or CAT6 is the preferred topology for new cabling. - Not to be discouraged, any plain telephone wiring, even 1-pair can be used to accomplish this.
Solutions:
The are several low cost solutions on the marketplace today that are certified for use in Australia/New Zealand telecom and can provide a simple plug and play operation.Solutions we recommend looking at are:
The Enable-IT 820 LRE - unpowered Ethernet line Extender (uses 2-pair telephone wire to drive 10MB Ethernet with dual active voice lines up to 182m) http://www.enableit.com/820.html
The Enable-IT 890 LRE - powered Ethernet line Extender (uses 1-pair telephone wire to drive 100MB Ethernet with single active voice line up to 1,830m) http://www.enableit.com/890.html
The Enable-IT equipment is a 1/3 (Third) of the cost of the Patton Electronics and Enable-IT is a local Australian based company with local stock.