Re: Network cables as security devices

Michael Shields (shieldscrosslink.net)
24 Aug 1998 07:50:14 +0000

• Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]
• Next message: Andrew J. Luca: "RE: Network cables as security devices"
• Previous message: borkinnetquest.com: "Re: Network cables as security devices"
• Maybe in reply to: Bruce K. Marshall: "Network cables as security devices"
• Next in thread: Andrew J. Luca: "RE: Network cables as security devices"

In article <35DB40AB.6291AD85feist.com>,
"Bruce K. Marshall" <bkmarshfeist.com> wrote:
> The "T"'s and "R"'s represent tip and ring -- or transmit and receive
> -- on the cable, so you could assume that by disconnecting pins 1 and 3 you
> would only eliminate any unwanted transmissions by your system.

No. A pair is made up of tip and ring; ethernet is made up of the 1/2
pair and the 3/6 pair. 1 and 3 do not form a pair; by disconnecting
them, you break both pairs.

You can prove this to yourself by making a rollover cable, which
connects two machines without a hub or two hubs to each other: the
wiring is 1-3, 2-6, 3-1, and 4-2. If 1 and 3 formed a pair, this
would not be a cable that reversed transmit and receive, but just an
ordinary cable with reversed polarity.

-- 
Shields, CrossLink.

• Next message: Andrew J. Luca: "RE: Network cables as security devices"
• Previous message: borkinnetquest.com: "Re: Network cables as security devices"
• Maybe in reply to: Bruce K. Marshall: "Network cables as security devices"
• Next in thread: Andrew J. Luca: "RE: Network cables as security devices"

This archive was generated by hypermail 2.0b3 on Sat Jul 17 1999 - 07:11:40 CDT