The purpose of this problem is to compare the cost of a regular international phone call (Mobile telephony network) and the same call but made using VoIP software installed on this phone using Cellular Data Connection.
Consider the case of a user subscribed to a Pay-As-You-Go cellular data service of a Mobile operator where he is charged $0.5 per consumed Megabytes (whether upload or download). This user wants to call a mobile number in France. The rate of the international call to France set by the mobile operator is 0.4$/minute.
1- Taking into consideration that the data rate is 12.2 kbps in each direction of a regular phone call, what is the cost per Megabyte of the regular international call?
2- The user decides to use VoIP software for international call. As you know, the total cost of the phone call is the sum of the VoIP service provider (VSP) rate and the fees that result from data usage (Mobile operator). The second part (data usage) is directly related to the audio codec used in the VoIP software of this VSP. In this problem, you are asked to compare this cost for two VoIP service providers.
a. Using Internet search, you are asked to look for two VSPs. For each VSP, you are asked to identify the rate of the international call (to France) and to describe the audio codec used by the VoIP software proposed by the VSP (The description should not be too long you are not asked to go into technical details). A key information to look for is the bit rate of the codec, which will be used in the second part of this problem.
b. Using the minute rate and codec bit rate information, find out the cost of a one-minute call to France for each VSP.
c. What is the cost per Megabyte of the call for each VSP?
d. Compare the numbers you obtained in part 2.c, with the number obtained in 1. What do you conclude?