On Wed, 29 Sep 2010, John BORIS wrote: > Somehow someone here figures I am a network layout guru and I got tagged > to guide one of our schools in restructuring their Network. I am looking > for some type of guide or spec that would say when it is best to use a > Home run to Network Center or to set up a Terminal Closet and have just > one (with a spare) run back to the Network Center. > > The current situation has the Server Room (Network Center) in the > middle of the school (well it is about 50 feet off of center). On one > side of the building they have a Terminal Closet and one home run from > the TC to the Server Room as it is about 150 ft from Network Center. The > other side of the building are Home runs to the Network center. That is > the side that is in question. Runs to a Terminal closet may be the same > distance as the network Center. > > I have to add 8 drops to this side and have been having this mental > battle. Add a TC, no add the home runs. Back and forth. So is there > such a Rosetta stone that says when you reach the x ft limit put a > terminal closet. Or should the longest run be one from the TC to the > Center and keep your runs from the Peripheral to the switch as short as > possible.
there is a max length for a single run, and you are best off staying well below that length (it assumes no connectors and minimal interference from other sources). If you are pushing what you consider reasonable (~200ft per this thread) then you are better off with the TC approach, you may be able to keep each hop under the distance going TC to the center, and even if you can't, the fixed wiring between the TC and the center is going to be higher quality (and therefor more reliable at long distances) than wiring going to equipment that may be moved over the years. If you are doing a long enough run that you want/need to go fiber, a TC is almost mandatory. Beyond that the issues you need to consider 1. cost (in $$ or hours) It's frequently easier (and cheaper) to have a few long runs and then a bunch of short runs from TC), remember to factor in the cost of the equipment (including power and cooling as needed) for the TC 2. flexibility home runs give you the best overall bandwidth, TCs and trunks can end up with bottlenecks. you may know how things are expected to be used now, but in 5 years what will be in those locations? right now you expect most of these locations to just be printers (which don't need much bandwidth to keep ahead of the printer speed), in a few years you may want to put wireless access points there where you will use every bit of bandwidth you have and wish for more. There are already commercial APs out there that want to be connected by a pair of trunked gig-E feeds to keep up with what they can do over the air. I've done both. I prefer to go with the home run approach where I can, but when I have to run all the wires, sometimes I go the other way. David Lang _______________________________________________ Tech mailing list Tech@lopsa.org http://lopsa.org/cgi-bin/mailman/listinfo/tech This list provided by the League of Professional System Administrators http://lopsa.org/
