Conference netcad::hub_mgnt

1538.0. "10BaseT config on DS900EF" by TROFS::WEBSTER (NIS, London, Canada) Fri Oct 07 1994 13:24

	Can the UTP ports of the DECbridge 900MX (aka DS900EF) be connected
to a UTP mau (DETPM)? Does this require cross cable? Is this a legal config.

	I could not find any confirmation on this, and my understanding of 
10BaseT is that you can connect repeater 10BaseT ports together to create a
10BaseT inter-repeater link. But these are repeater ports, and I am not sure 
about end-node ports such as those on the DB900 or a UTP mau.


	+-----+				+---------+
	|DB900|				| AS400   |
	|     |			 +-----+|	  |
	|    3|<---------------->|DETPM||	  |
	|     |	   BN26K??	 +-----+|	  |
	|     |	or BN25G??   		|	  |
	|     |	or BN24F??		+---------+
	|     |
	|     |				+---------+
	|    4|<----------------------->| DR90T   |
	+-----+	   BN26K or BN25G	+---------+

	-Larry

    The BN24F-XX cable (this is a crossover cable), is what would
    be used to connect a UTP port of a DS900EF to a UTP MAU. 
    This is a legal configuration. Of course you must have the MAU
    connected to something which can provide power to it. Otherwise
    the bridge UTP port will not see a valid link.
    The UTP ports on the DS900EF are internally straight-through
    wired station ports. Repeater ports are internally crossed-over.
    So a connection between a UTP port of a DS900EF and a Repeater
    requires a straight-through cable.
    A MAU does not cross-over the connections. So for a connection
    from a UTP port of a DS900EF to a MAU you need one cross-over.
    
    Bob

	Thanx for the fast response.

	-Larry