00338nam a2200133Ia 4500001000500000005001700005008004100022020001500063082001400078100002600092245003000118250001200148650004400160526520261006003841.0120911s9999    xx            000 0 und d  a0029463998  a004.6 STA  a Stallings, william.   a Isdn and broadband isdn   a2nd ed.  a Intergrated services digital networks