IP telephony networks require the same security measures as those implemented on an IP data network. Which of the following is unique to IP telephony?

A.
Limiting IP sessions going through media gateways

B.
Identification of rogue devices

C.
Implementation of authentication

D.
Encryption of packets containing sensitive information

Explanation:
A: A media gateway is the translation unit between disparate telecommunications networks. VoIP Media Gateways perform the conversion between Time Division Multiplexing
(TDM) voice to Voice over Internet Protocol (VoIP). As a security measure, the number of calls via media gateways should be limited. Otherwise, media gateways are vulnerable
to denial-of-service attacks, hijacking, and other types of attacks.
B is incorrect because it is necessary to identify rogue devices on both IP telephony and data networks. On IP telephony networks, it is necessary to look specifically for rogue
IP phones and softphones. Rogue means that these devices are unauthorized. They are therefore not managed or secured by IT and can introduce additional risk to the
network. A common rogue device found on data networks is wireless access points. A rogue access point can provides an entry to the network for unauthorized users.
C is incorrect because authentication is recommended for both data and voice networks. In both cases, authentication allows you to register users and equipment on the
network so that you can verify they are who they say they are when they try to connect to the network. Authentication also allows you to deny access to users and devices that
are not authorized.
D is incorrect because sensitive data can be transmitted on either a voice or data network and should be encrypted in both cases. Eavesdropping is a very real threat for VoIP
networks. Consider all the sales meetings, management meetings, financial meetings, etc., that are conducted over the phone. Every word that is spoken in those meetings is
vulnerable to eavesdropping. Encrypting voice data is one of the best ways to protect this sensitive data.