PGP VOIP - Privacy Encryption and Security

"This purpose of this article is to discuss two of the most well known attacks that can be carried out in current VoIP deployments. The first attack demonstrates the ability to hijack a user's VoIP Subscription and subsequent communications. The second attack looks at the ability to eavesdrop in to VoIP communications. Although VoIP is implemented using various signaling protocols, this article focuses on attacks associated with the SIP (Session Initiation Protocol), an IETF standard (RFC 3261). The two attacks, among others such as DoS, have been discussed in various research papers but they haven't been acknowledged publicly as active attacks."

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