Assuming no cRTP or header compression. How many VoIP G.729 calls can be made
simultaneously over a 128-kb/s Frame Relay circuit (Layer 3) if 50 percent of the circuit is
dedicated to voice and 50 percent is dedicated to data?
A.
1
B.
2
C.
3
D.
4
E.
5
Explanation:
Bandwidth Calculation Formulas
These calculations are used:
Total packet size = (L2 header: MP or FRF.12 or Ethernet) + (IP/UDP/RTP header) + (voice
payload size)
Codec bit rate = codec sample size / codec sample interval
PPS = (codec bit rate) / (voice payload size)
Bandwidth = total packet size * PPS
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