H

H.263, 700

Handley, Mark, 589

handoff

• in 802.11 subnets, 546–547

• in GSM, 577–580

• in wireless networks, 524

handshaking, 93

• SSL, 633, 636–637

• TCP three-way, 102, 165, 234, 256–257, 504

hard guarantees, 710

hash functions

• checksums and, 611–612

• cryptographic, 611–613

• digital signatures using, 616

• MD5, 612, 614

• SHA-1, 613

HDLC. See high-level data link control

header length field, 236

header lines, 104, 106

headers

• IPv4, 331–332

• MIME, 630

• MPLS, 492–493

• RTP, 702

• Web browsers and, 107–108

head-of-the-line blocking (HOL blocking), 322

HELLO message, 394

HFC. See hybrid fiber coax

hidden terminal problem, 528, 540–542

hierarchical architectures

• within ASs, 394–395

• in data center networks, 497–498

• DNS distributed database, 130–134

• Skype peers, 698

high bit rate, 676

high-level data link control (HDLC), 451

HLR. See home location register

HMAC, 614

HOL blocking. See head-of-the-line blocking

home agent, 562

• discovery, 570, 571–572

• indirect routing and, 565–566

• registration with, 572–573, 574

home location register (HLR), 575

• call routing and, 576–577

home MSC, 575

home network, 562, 575

home public land mobile network (home PMLN), 575

Home Subscriber Service (HSS), 559

hop limit, 351

host addresses, obtaining with DHCP, 342–345

host aliasing, 128, 136

hostname, 126–127

• alias, 128, 136

• in DNS queries, 132–133

• in DNS resource records, 135–137

• DNS services and, 127–128

hosts, 2, 9, 11

• data center, 495

• wireless, 520

Hotmail, 126

hot potato routing, 400–401

HSPA (High Speed Packet Access), 557

HSS. See Home Subscriber Service

HTML, development of, 63

HTML file, 98

HTTP. See HyperText Transfer Protocol

HTTP byte-range header, 687

HTTP GET message, 504

HTTP protocol, 50, 63

HTTP request, 502

HTTP response message, 505

HTTP streaming, 148–149, 681

• adaptive, 681

• client application buffer, 685–686

• DASH, 148–149, 155, 688

• early termination, 687–688

• prefetching video, 684–685

• repositioning video, 687–688

• TCP buffer, 685–686

• YouTube use of, 156

hub, 475

HughesNet, 16

Hulu, 679

hybrid fiber coax (HFC), 14–15, 439

hyperlinks, 102

HyperText Transfer Protocol (HTTP), 96–97, 98–100

• cookies, 108–110

• ICMP and, 419

• message format, 103–108

• non-persistent connections, 100–103

• persistent connections, 100, 103

• ports, 199–200

• request message, 103–105

• response message, 105–108

• SMTP comparison with, 121