Voice of Internet Protocol is the next generation telecommunications method. It allows to phone calls to be route over a data network thus saving money and offering increased features and productivity. All these benefits come at a price, vulnerability. It is easier to attack and exploit a voice and data network. VoIP will need extra security measures beyond the standard security that is typically implement for a computer network. Many issues need to be addressed such as type of attacks, security, quality of service and VoIP protocols.
There are many VoIP protocols in the market. Some are proprietary while others are open standards. The two most popular open protocols are H.323 and SIP. They were designed by two different organizations and operate slightly differently. They both have problems with the use of random ports problems with NAT translations and firewalls.
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