Download Security Considerations for Voice Over IP Systems, This document is published by National Institute of Standards and Technology, this covers the following: summary of VOIP, VOIP equipment, Quality of Service issues, summary of VOIP data Handling ,Cost, Privacy and Legal problems with VOIP, VOIP Security issues,Speed and Quality, H.323, SIP gateway Decomposition, Firewalls, Address Translation, and call establishment, encryption and IPsec, Solutions to the VOIPsec issues, planning for VOIP deployment, VOIP Risks, Threats, and Vulnerabilities.Download the pdf from below to explore all topics and start learning.