Index_V

V

variants on 802.11, 19–24

VBS/Timo-A virus, 76

very high bit rate DSL (VDSL), 24

video, online, 299–300

videotelephone, 165

virtual carrier sense protocol, 147–148, 147

virtual LAN (VLANs), 90, 257, 262, 288

virtual private network (VPN), 38–39, 62, 94–99, 96, 256, 331

IPSec in, 97

L2TP over IPSec in, 98

LAN to LAN types, 95

layer 2 tunneling protocol (L2TP) in, 98

network address translation (NAT) in, 99

point-to-point tunneling protocol (PPTP) in, 98

port address translation (PAT) in, 99

remote access types, 95, 96

secure sockets layer (SSL) in, 98

security and, 82–83, 94–99, 96

SOCKS network security protocol in, 98–99

standards for, 97–99

tunneling in, 94–96

vulnerabilities of, 97

virus infection, 76–77

Vivato, 112, 243

voice activation detection (VAD), 126

voice over IP (VoIP), 7, 121, 157–198, 300–305

advantages of, 301–305

applications for, 161, 192–195

architecture of, 192–195

CELP coding in, 184

challenge of, 159–160

circuit switched speech coding in IP telephony and, 184, 185–192

codecs for, 162, 179–184, 180

Communications Assistance for Law Enforcement Act (CALEA) and, 172, 190–192

compression/decompression in, 162–163, 178

cost savings of, 273–277, 277, 301–305, 305

digitization process in, 162

dropped packets in, 177–178, 187

echo in, 187

emergency services (E911) and, 172, 190–192

encoding process in, 180–184

endpoints in, 163

G.711 codec in, 181–182, 186, 187–188, 188

G.723.1 ACELP codec in, 182

G.729 codec in, 182–184, 182

GIPS enhanced speech processing in, 186, 187–188, 188

H.323 in, 163, 164–165

IP telephony and, 192, 193–194, 193

jitter in, 178, 186

latency and, 175–177

Lockheed Martin Global Telecommunications (LMGT) evaluation of, 187–188

mean opinion score (MOS) in, 173–174, 183

media gateway control protocol (MGCP) in, 163

MEGACO in, 163

multiprotocol label switching (MPLS) in, 137–139

objections to, 172–178

origins of, 161

packetization in, 162

perceptual speech quality measurement (PSQM) in, 173, 174–175, 175

personal digital assistants (PDAs) and, 160, 195

private branch exchange (PBX) and, 194–195

quality of service (QoS) and, 164, 172, 173–178, 332–333

range of signal in, 172

routing in, 163

security and, 189–190, 189

session initiation protocol (SIP) in, 163, 165–167, 166, 302

short message service (SMS) and, 194

signaling protocols for, 163–167, 164

softswitches in, 167–170, 170, 192

software for, enhanced speech processing, 185–186

speech coding in, 179

switching in, 167–172

telephones for, 193–194, 193

Wireless Fidelity and, 192

wireless Internet service providers (WISP) and, 196

wireless LANs (WLAN) and, 192