QUESTION
a) National regulations require the availability of the following services for all IP to PSTN, PSTN to IP, and IP to IP calls. Name any three types of these features
b) It is often heard that IP Telephony is not secure if media streams are not encrypted. Do you agree with this statement, give valid reasons to support your views
c) Compare UDP and TCP
d) Differentiate between the Transport layer and the Network Layer of the OSI Model