00390nam a2200157Ia 4500 210716s1994 xx 000 0 und d 9780672305016 eng 004.65 HELG Held, Gilbert. Understanding data communications. 1 USA SAMS publishing 1994 xvii.435 Computer Networks 187884 187884 0 0 0 0 MCA AIMIT AIMIT 2021-07-16 0 004.65 HELG MCA07392 2025-07-21 00:00:00 2021-07-16 BK