Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!samsung!olivea!mintaka!bloom-beacon!eru!kth.se!sunic!mcsun!ukc!mucs!logitek!sph From: sph@logitek.co.uk (Stephen Hope) Newsgroups: comp.dcom.lans Subject: Re: 10Base-T hubs Message-ID: Date: 15 Apr 91 16:15:29 GMT References: <1991Apr03.004515.12021@rs6000.cmp.ilstu.edu> <2230148@hprnd.rose.hp.com> Organization: Logitek Plc. Lines: 34 pat@hprnd.rose.hp.com (Pat Thaler) writes: >> > >> >- is there any advantage to "cascading" hubs (attaching the next one to a >> >port in the previous one - you lose two ports) as opposed to putting both >> >directly on a thin/thick backbone and using all ports for the UTP star? >> Lose two ports? If you are connecting two "out" ports together, you will >> have problems. To cascade, you need to connect an out port of the parent, >> to the AUI port of the child, with a 10BaseT transceiver. Without the tree >> heirarchy, the timing gets all crunched and one or both of the hubs will >> stop working until the problem is corrected. >There seems to be some confusion here. Perhaps it's because 1BASE5 >(1 mb/s twisted pair version of IEEE 802.3, usually called StarLAN) >had hubs it a special port to cascade to the next higher hub. In >any 10 mb/s IEEE 802.3 repeater, any port can be connected to another >repeater port. Repeater operation, timing, etc are the same for all >ports. >There is one thing you should check when connection repeaters together >by their twisted pair ports. Pins 1 & 2 are the TX pair for DTEs >and pins 3 & 5 are the Rx pair for DTEs. Inorder to allow wiring Try pins 3 and 6 for the TX pair. >Pat Thaler Stephen Hope #include