H

H.323 protocol, 258

Hammer Call Analyzer, 128

hard phones. See also phones

Asterisk, 325

Avaya communication devices, 256257

Cisco, 207210

hardening

Cisco phones, 247248

Cisco switches, 246247

network perimeter, 135

networks, 135136

servers, 136

VoIP phones, 136

help pages, 1213, 17

hijacking

network, 169

reghijacker tool, 445455

REGISTER requests , 446452

registration, 186, 438456

SIP phones, 438456

HINFO information record, 27

host-based intrusion prevention, 310

host/device discovery, 3243

host/device identification, 4753

hping2 tool, 41

hubs, network, 149150

HYPERLINK standard, 154