Noob punchdown question

Hi Networking guru’s

I watched a few video’s about punchdowns but usually its clearly marked where the half coloured/half white wires are supposed to go.
With the patchpanel I have in front of me I just have no idea.
I need your wisdom.
Sincerely,
A Noob

That’s a pretty fucking weird patch panel.

But, where it says ‘A’ or ‘B’ on the PCB, you’ll want to use the ‘B’ standard.

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Generally in the past you would use crossover cables on switch to switch or switch to router connections and that could be either A to B or B to A. So long as both ends terminate the opposite you were golden. I’m not sure it matters anymore since just about everything will auto negotiate transmit/receive pairs.

@AnotherEpicName It seems to me like you would just punch down the normal order for B. If you dont know already this it what it looks like:

note the numbers and adjust accordingly with the the numbering on your punch down. For the A standard you would swap orange and green.

EDIT: corrected information about connections

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@Adubs Thanks, I had no idea the numbers corresponded with the colours.
Now it makes more sense why the numbers were ordered that way :slight_smile:

Also, I just noticed I ordered an UTP 6a patchpanel and they sent me the (more expensive) STP 6a
Don’t supporse this would be any problem but just wondering.

This is what the patchpanel I should’ve normally gotten would have looked like

Will it hurt if you use UTP on STP? Nope. But the STP will be grounded, if this is important to you then you need to use STP cables.

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I dont think it matters other than offering a ground for the shielding but if youre using UTP then nothing to worry about then.

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Thanks for the quick response’s and clarifications.
This forum has been a great help as always :smiley:

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Be aware that auto-negotiation was not part of the 100 megabit ethernet standard, and some (stubbornly, standards-only compliant) 100 megabit devices may not do auto-negotiation properly or at all.

CISCO gear in particular is prone to not auto-negotiate properly or at all on 100 megabit ports.

So whilst it “shouldn’t matter any more”, i’d definitely suggest doing it properly :slight_smile:

It’s one of those things that may not ever bite you in the ass, until it does…

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You’re right but I haven’t seen a piece of equipment that hasn’t done it in over a decade. Cisco included. Plus imo 100 base t has no business in the wild anymore but maybe I’m spoiled. Either way that’s why I gave him the nugget of knowledge about crossover cables so he can do it right.

Lol my work’s entire network infrastructure is 100baseT. We have CAT6a runs but only 100Mbit CISCO switches.

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My heart goes out to you. My company is only about 28 employees and we are beginning to saturate gigabit at times with our network storage. We had a couple of machines auto negotiate 100mb on certain switch ports and it shit on their performance since everyones PST files are on the NAS. We also have an in house ERP system that is executed from the network. You can feel it when everyone is busy.

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It really depends on your environment. For a typical office worker, especially cloud connected, 100 megabit switching is fine.

Also, if you’ve had an existing VOIP deployment for some time with VOIP handsets that use POE - for a very long period of time, CISCO have been raping you on $ per port for gigabit POE.

Gigabit is/was cheap
100 megabit POE is/was cheap

Gigabit POE, below a certain size deployment was expensive (at least where i am it was something like $30-40/port for 100meg POE vs. $100/port for gig POE - roughly, from memory - for a 48 port layer 2 switch - prices in AUD).

Once you get up into the chassis switches that changes somewhat and the step to gig POE isn’t anywhere near as big, but for a small office deployment saving 50% on the workgroup switch is a significant saving.

Hence, there’s quite a lot of 100 megabit POE out there in the wild, still. My smaller regional offices are mostly 100 megabit POE at the desktop.

If you’re not doing POE, and/or not running CISCO gear then you’re probably not facing that sort of dilemma, but if you’re an all Cisco network (for various reasons), it was a bit of a shit sandwich…

edit:
you’d be amazed how little traffic a typical “office” worker generates. For some real world “typical office user” stats (from my HQ which is gig-POE at the desktop)…

I’ve got a bunch of 4506s (Sup7-LE) in the office here with 2x10 GbE LACP port channels back to a central 4507 (Sup7-E with 4x 12 port 10 gig SFP line cards and 1x 48 port gigabit). 240 ports in each 4506.

About half the ports on each 4506 are in use (we deploy 2 ports per desk in case someone needs to share a desk, has a visitor, whatever), so in theory i have 120x gigabit connected users per switch, oversubscribing a 20 gigabit uplink at 6:1 contention or thereabouts.

Average usage on the uplinks is generally under 5%… 95th percentile traffic for example on the 4506’s uplink that i am connected to (which has IT/power users on it) is 32 megabit. Peaks to 150 megabit (over 15 minute average).

Typical office users just don’t do a lot of traffic - and in a lot of cases, gigabit is a waste. I’m not deploying 100 meg anywhere anymore, but could still get away with it if i had to.

For servers, stuff doing NFS or iSCSI, etc. - 10 gig or faster is really what you want. But thats as much to do with command latency as throughput.

/tangent :smiley:

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