00301nam a2200121 a 450000500170000002000150001708200150003210000230004724500370007025000120010726000350011930000250015420251203110613.0 a8129702061 a004.6bSTA aStallings, William aData and Computer Communications a7th ed. aDelhibPearson Educationc2004 axvi,847p.c24 cm. PB