Conference netcad::hub_mgnt

1525.0. "DECrepeater 90T and PCs hang" by GIDDAY::STANISLAUS () Tue Oct 04 1994 22:38

    
    	A customer has several DECrepeater 90T units in several DEChub 90s
    and also several DECrepeater 90TS and DECrepeater 900TM units in DEChub
    900 Multiswitch. 
    
    	The customer has cheap Ethernet controller cards in his PCs bought
    from several cheap suppliers. 
    
    	These cards have clock jitters in excess of IEEE UTP specs of 10
    Mhz +/- 0.01 %. Hence these cards do not work with our DECrepeater 90T
    units probably because of a smaller FIFO in the 90T repeaters.
    
    	These cards work fine with DECrepeater 90TS and DECrepeater 900TM
    and also Synoptics Repeaters which this customer has. I can give a big
    technical talk and talk to him for a few hours trying to convince him
    that it is not Digital's problem and that their PC Ethernet cards are
    outside of IEEE UTP specs. I may win the battle, yet loose the war;
    because the customer will either convince the Digital's Account Manager
    to replace all his 90T units with 90TS units or go to Synoptics and buy
    more of their repeater cards.
    
    	I wonder what other Territories do - US/Canada, Europe - in a
    situation like this. We are talking about dozens of 90T units and hence 
    thousands and thousands of dollars. This customer is the state wide 
    Education Services Organisation in New South Wales State in Australia.
    
    Alphonse
    
    Alphonse