why haven't ethernet connectors changed?
cabenth at gmail.com
Fri Dec 21 15:34:09 UTC 2012
You didn't include RJ11 in your question.... it goes back further.
One reason is that as we push the limits of cable from CAT3 (10meg) to CAT5
(100meg) to 5E (gig) to 6 (not sure what that was for) to 7 (10gig), the
cable doesn't get any smaller. We're dealing with higher and higher
frequencies of changes on the wire. This makes cross talk and interference
a bigger problem, so the twists and insulation are more important to try to
protect from those issues (sometimes shielding). So the cable hasn't gotten
any smaller. The connector works well enough and allows for these distances
to be maintained. Some vendors have found ways to maintain the twists
farther into the RJ45 by essentially using traces and not just lining the 8
wires up in parallel but stacking them in a staggered fashion...
Obviously, a new connector could have been found, but why haven't we
changed the C13 that HP came up with (at least I think they did) back in
the 50s? Its still the defacto standard for all computer input power. As a
matter of fact, most NEMA specs haven't changed since they were created...
If it ain't broke, don't fix it. The only problem with the RJ45 is the hook.
On Fri, Dec 21, 2012 at 7:15 AM, Brielle Bruns <bruns at 2mbit.com> wrote:
> Some of us still have a stock of legacy gear and cables - things like v35
> cables for connecting to CSU/DSUs, and even the occasional AUI hub. :)
> You wouldn't believe how much people will pay for legacy computer gear
> when they need it to keep their business going.
> Sent from my iPhone
> On Dec 21, 2012, at 7:57 AM, Matthew Black <Matthew.Black at csulb.edu>
> > Only $55.95 for a 3-foot transceiver cable. What was more surprising is
> that Black Box is still around.
> > matthew black
> > california state university, long beach
> > -----Original Message-----
> > From: Michael Thomas [mailto:mike at mtcc.com]
> > Sent: Thursday, December 20, 2012 10:20 AM
> > To: NANOG list
> > Subject: why haven't ethernet connectors changed?
> > I was looking at a Raspberry Pi board and was struck with how large the
> > connector is in comparison to the board as a whole. It strikes me:
> > connectors haven't changed that I'm aware in pretty much 25 years. Every
> > cable has changed several times in that time frame. I imaging that if
> > cared, ethernet cables could be many times smaller. Looking at wiring
> > etc, it seems like it might be a big win for density too.
> > So why, oh why, nanog the omniscient do we still use rj45's?
> > Mike
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