See also ATM entries available time, 199 cell delineation and scrambling, 520 avalanche photodiode (APD), 238-239 cell structure, 516-520 average, 60 cell transport, 533-537 average busy season busy hour (ABSBH), 57 connection-oriented and connectionless services, 526-528 back porch, 408 defined, 513 backward direction signaling, 150, 161 layering and B-ISDN, 521-526 backward explicit congestion notification (BECN) network management in, 568-571 bit, 331, 333, 335, 511 quality of service, 531-532 backward indicator bit (BIB), 371 routing and switching, 528-530 backward information messages, 384 signaling requirements, 530 backward sequence number (BSN), 370, 371 traffic/congestion control, 532-533 balanced configuration, HDLC, 284 user-network interface and architecture, 514-516 balance return loss, 77, 78, 189 asynchronous transmission, 260-261 balancing (impedance matching), 76-77 AT&T (American Telephone and Telegraph), 16 balancing network (N), 76f, 77 AT&T digital data system (DDS), 277-278 bandwidth, 34, 330 AT&T 5ESS switch, 136 better use of, 328 ATM adaptation layer (AAL), 523-526 cellular radio, 468 AAL-0 category, 524 grant per connection, 355 AAL-1 category, 524 grant per subscriber station, 355 AAL-2 category, 524-525 modem selection and, 273, 274 AAL-3/4 categories, 525-526 multiplexing and, 78-79 AAL-5 category, 526 radio system, 196 ATM cells, 516-520 RF, 36-37 cell loss priority field, 519 television, 403, 406 generic flow control field, 517-518 3-dB power, 34f header for, 528 of a twisted pair, 34 header error control field, 519-520 bandwidth request message, 356f idle, 520 bandwidth requests, types of, 355-356 INDEX bandwidth segments, 79 probability of, 58 baseband, bandwidth of, 414 block check count (BCC), 255-256 baseband response, bandwidth of, 414 block codes, 256 baseband transmission, 28 blocked call, 58 LAN, 292, 294-295 blocked numbers, 6 base station (BS), 348 blocked operating condition, 157, 158 basic error correction method, 369 blocking probability, 8, 142 basic service set (BSS)