 (HDSL), 272 service examples, 56 High-Density Bipolar 3 (HDB-3), 154, structure, 55-56 Interested parties, 10-11 High-level data link control (HDLC), 241 Interference, 127, 145 High-speed circuit-switched data Interior Gateway Protocols (IGPs), 316-17 (HSCSD), 228 International mobile equipment identity Home location register (HLR), 192-93 (IMEI), 227 functions, 214 International mobile subscriber identity GSM, 214 (IMSI), 227 See also Visitors location register (VLR) International networks, 46-47 Host-to-host protocols, 319-27 defined, 46 TCP, 319-26 illustrated, 47 UDP, 326-27 International prefix, 31 HTML, 334-37 International standards, 8, 9 common tags, 336 International Standards Organization defined, 334 (ISO), 6, 14 documents/source file, 335 International Telecommunication Union Hybrid fiber coaxial cable (HFCC), 277 (ITU), 13-14 Hypertext Transfer Protocol (HTTP), 328, ITU-R, 14-15 332-34 ITU-T, 13-14 defined, 332 Internet, 301-41 request methods, 333-34 application layer protocols, 327-31 requests, 332 ARP, 315-16 requests/replies procedure, 332-33 defined, 49 development, 301-2 ICMP, 317-18 example connection, 304 defined, 317 host-to-host protocols, 319-27 operation, 318 ICMP, 317-18 problem types, 317-18 IP, 306-16 IMT-2000, 208 protocols used in, 302-5 Information networks, 357-58 routing protocols, 316-17 Initial address messages (IAMs), 37 structure, 318-19 Institute of Electrical and Electronics summary, 341 Engineers (IEEE), 12-13 VoIP, 337-41 Integrated Services Digital Network WWW, 321-37 (ISDN), 6, 17, 49-51, 268-69 Internet Activities Board (IAB), 301 advantages, 50 Internet Engineering Task Force (IETF), basic rate interface, 50, 268 14, 301 connection illustration, 268 Internet Message Access Protocol defined, 49 (IMAP), 327 DSL, 271-72 Internet Protocol (IP), 306-15 primary rate interface, 269 addresses, 306-8 Intellectual property rights (IPRs), 15 address format, 307 Intelligent networks (INs), 39, 53-56 bearer network protocols, 305-6 centralized intelligence, 54-55 defined, 306 Intr