G

gateway

selecting for VoIP service, 318

VoIP and, 310

geographic routing

for large businesses, 79

for small-to-midsize businesses, 74

groundstart protocol, 138

growth

analyzing phone line needs and, 24

Centrex/Centranet and, 27–28

key systems and, 29

planning for business, 20–21

G.711 codec, using uncompressed VoIP with, 315–316

G.729 codec, using compressed VoIP with, 316