00478    a2200181   4500020001800000082001500018100001800033245005900051250000900110260004500119300002100164650000800185650002100193650002700214650002200241650002000263650001300283  a9788178080987  a004.6bHAL  aHalsall, Fred  aData commiunication computer networks and open systems  a4th.  aNew DelhibPearson Educationc1996g1996  axvi, 907p.c24cm  aLAN  aComputer Science  aComputer Communication  aData Transmission  aInternetworking  aWANaWAN