One of the things I want to do with the office network cabling setup is to put all the network gear into a wall cabinet so it's all hidden away. My fear has been that this was all going to go horribly wrong when it came to moving the ADSL modem, because the phone socket is in the opposite corner from the putative network hub.

Ah, but I can connect the phone line through the network cabling! A very neat solution, since this would run the phone line right into the network cabinet, exactly where it needs to be.

However I needed a cable to connect the phone socket (an RJ-11 plug) to the neighbouring network socket (an RJ-45 plug), and another cable at the other end to take the phone line from the patch panel to the ADSL modem. I needed an RJ-45 cable crimper in any case, and made sure that it had an RJ-11 crimping bit in it too for exactly this reason.

I found out last night that I needn't have bothered. RJ-11 plugs go into RJ-45 sockets just fine.

Doing research on the wiring for the RJ-11/RJ-45 patch cables I found out that the wiring pattern I am using for the network wiring is compatible with telephone wiring. It took me a long time to finally twig that the only reason this could possibly be meaningful would be if the phone plugs would connect to this network wiring directly, in other words if it was possible to plug a phone into a network socket.

Since the words "you can plug RJ-11 plugs into RJ-45 sockets" were not written down anywhere, I simply had no clue that this was the case until I had seen about a dozen wiring equivalence diagrams between flat telephone cable and twisted pair network cable at which point a lightbulb went on in my head. Trying it out last night confirmed the point - no special patch cables are required. Hooray!

This compatibility with telephones, incidentally, is exactly the reason for the annoying layout of wires going into network plugs that I was complaining about the other day. It's still an annoying layout, but it seems to serve a real purpose so I am reconciled to it at least.

Last night I wired up another two ports, so that's four out of eighteen. I'm going to change my strategy though, so that rather than wiring up ports and their corresponding patch panel sockets in parallel I shall do everything on the patch panel in one go. This is mainly because I want to minimise the mechanical stress on the patch panel and its already connected wires, but also so that I can build up some momentum on this and get the job done. Two ports a night would put me finishing in the middle of next week, which is too slow.

And then at some point I will have to make the short network patch cables to go inside the network cabinet, which is the main reason I bought the cable crimper. Quite apart from the cost of buying network cables, none of the ones I've seen on sale are less than three feet long (about 90cm). That's just too much wire to fit into a small cabinet, so I decided to use the offcuts from the wiring install to make shorter cables which won't clog the space too much.

Making the cabinet is something else entirely.

Posted by Dunx at August 4, 2004 11:38 AM