August 1999
Intermediate to advanced
328 pages
8h 50m
English
It is obvious that VoIP means much more than the sole use of IP to support speech traffic. This chapter has explained several widely used layer-1 and layer-2 technologies to support IP, operating at layer 3, as shown in Figure 6-1. A few hardware and software vendors may use proprietary schemes, but they are in the minority. The ability of the user and an ISP to communicate with each other at the physical and data link layers rests on the standardized implementation of the V Series recommendations and PPP.