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Hardware Networking FAQs?
TufelKinder asks: "Our company is installing a new network at a new building location. There don't seem to be many discussions that center on the best cabling systems, etc, to use. I'm wondering what /. folk have found to be the best brands/types of copper cables to use for 10/100BT networking and for gigabit over copper as well. Are there any specific types of cable or cabling practices to avoid?"
I am not a network expert, so take this with a grain of salt.
Get the best cable you can get at a reasonable price installed everywhere. Don't get the super-duper-will-be-good-for-1000-gigabits sort of cable. But do wire the desktops with a decent Cat-5e that will let you run gigabit when the price comes down for it so you don't have to do it again. And you know that, at some point, many users will start to need gigabit performance on their desktop. It's inevatable.
Make sure that you follow fire safety code. Only certain types of cable can be run through the walls.
Cable management is a very important consideration. The best system is one that lets you add more wiring whenever you want, keeps the cables neat, etc. I know part of it is making sure that you have ample conduit space through the walls, so you can run more cables later on. I know that another part of it is having those faceplates that let you add more jacks.
Do try to wire every room, even if it seems stupid. You never know what will happen later on.
Don't run everything through the same conduit set. Running power cables next to network cables is dangerous, stupid, and not good for network reliability. I think that's also against most building code.
You might want to wire the phone cables with Cat-5 or better, stupid as it seems. IP telephony is taking off and those might end up being used to wire up netphones.
Get a raised floor where all of the servers and hubs will be.
Try to have things set up so that you have no long cable runs. This may mean several networking/telephone closets. I'm not sure what the good maximum length is, so somebody else will have to fill that in.
Keep a map of what is cabled where. And keep it up-to-date.
Gentoo Sucks
Make sure you plan some space on every floor for a wiring closet while you still can; more than one for larger floors. Place them so you don't have to do more than about 50m from the closet to workstations. Use cat5 cable from the closets to where people will work. If any consultant or network type tells you to use cat6, fire him.
Plan for at least four patches per desk; people will bring in laptops, or put double the number of people in an office. Don't forget the absolute minimum is two patches per person (computer, phone), and the minimum will last you about a month before people start bringing in little hubs to put on their desk (which you want to avoid).
Between the wiring closets, use fiber. It's not as expensive as you may think, and terminating is quite painless -- many switches have fiber ports or room for fiber modules. You can also use fibercopper transceivers, not too expensive. Use single mode (SM) fiber. You need to do this because a) it can go much longer distances, b) you can happily string it alongside power lines if you need to, and c) because you can upgrade uplinks to gigE without worrying about the cabling.
You'll also need to get copper into the wiring closets though, for connecting the PBX to the phones. Distance isn't such a big problem for those.
If at all possible, get double the number of fiber links that you strictly need. Ideally, string it on different sides of the building or floor. You can't crimp it like you can cat5, and getting fiber types in for a splice takes a while. In a pinch, when one gets cut, it's good to have a guaranteed extra link ready, which is undamaged through following a completely different route.
In the wiring closets, put switches, not hubs. Don't use hubs at all, in fact.
Don't forget that the big cost in laying wire (both cat5 and fiber) is in man-hours, not the terminating equipment or physical cable. Putting in 10 cables isn't that much more expensive than putting in 1, in other words.
having the server on a gigabit and clients on 100 meg won't cause errors... tcp/ip was designed with the thought in mind that not all network connections are created equal.
(simplisticly) the client will only ack as fast as it recieves data, and the server will only send data a certain amount over what has been acked, so the server won't saturate its network connection if its saturating the client's
Need a Catering Connection
... that I've been asked to help with. The URL will eventually be http://networking.beyondboxes.net. Several folks around here, a few even from my company, have been working on it for quite some time. FAQ's, message boards, howtos, and even some insight on the future trends of networking. It should be a great help when it's done sometime in October. Until then, I'll see if I can't dig out some good URLs to paste on this thread.
...the part about single mode fiber. Within a typical building it's just plain overkill. Multi mode is cheaper, easier to work with, and the transceivers on either end cost so much less than single mode transceivers that it ain't even funny. Multi mode is the safe way to go. String fiber between the closets for sure. The original poster didn't describe their building much (at all?) IIRC. One closet per floor as long as that closet can reach every possible corner of the floor at around 75m. Some push it to the limit, some say 50m. Just be aware of your length; that's the cable tray path, not as the crow flies. Don't forget to allow for jack to CPU cable and patch length too. If you're going to have more than one closet, pick a closet to be the central closet. Say you have 4 floors to wire, 2 closets per floor. String a couple pair of MMF from each closet down to the 1st floor closet and call that your main. Do you best to only have two layers within your building too, if possible. 100FX will probably be more than enough for your infrastructure. GigE is ok too. It costs more though and you have much greater distance limitations. 100FX can run 6,561ft over MMF. GigE can only run 1,443ft over 62.5 micron MMF (the most common) or 1,804ft over 50 micron MMF (double check that last figure). You can always trunk two 100FX lines together. Hell with a wavelength devision multiplexor you can double your bandwidth over the same pair of MMF. Draw a good plan, measure everything, use fiber for your infrastructure, 10/100 to all access ports, put the server got a given area closer to the users it serves, AND buy managed devices. I find the last one to be very important. You can buy Cisco if you want. It's up to you. We're a Cabletron shop (Enterasys now) and are doing fine. I'm not fond of 3Com personally but I know some love them. I really don't like HP. Your choice though. With a managable device, you can monitor and graph bandwidth usage as well as do diagnostics (sniffing via port mirroring) much easier.