00377nam a2200145Ia 4500008004100000020001500041041000800056082001600064100001900080245003900099250000600138260005200144300001300196650002200209210716s1996    xx            000 0 und d  a8120310802  aeng  a004.65 HELG  aHeld, Gilbert.  aUnderstanding data communications.  a4  aNew DelhibPrentice Hall of India PVt Ltdc1996  axvii,431  aComputer Networks