tailieunhanh - Understanding Voice over IP Signaling Protocols in Cisco Telephony Implementations

Understanding the specific functions Voice over Internet Protocol (VoIP) signaling protocols perform plays a critical role in designing, building, maintaining, and troubleshooting a Cisco VoIP implementation. Each protocol also plays a direct role in implementing different features, services, technologies, as well as in product selection and integration. Specifically, Cisco has predominately implemented the following five different signaling protocols amongst their rapidly expanding telephony product line:. | Global Knowledge Expert Reference Series ofWhite Papers Understanding Voice over IP Signaling Protocols in Cisco Telephony Implementations 1-800-COURSES Understanding Voice over IP Signaling Protocols in Cisco Telephony Implementations Chris Olsen Global Knowledge Instructor CCSI CCNA CCNP CCVP Introduction Understanding the specific functions Voice over Internet Protocol VoIP signaling protocols perform plays a critical role in designing building maintaining and troubleshooting a Cisco VoIP implementation. Each protocol also plays a direct role in implementing different features services technologies as well as in product selection and integration. Specifically Cisco has predominately implemented the following five different signaling protocols amongst their rapidly expanding telephony product line MGCP Media Gateway Control Protocol Skinny SCCP Skinny Client Control Protocol SIP Session Initiation Protocol CTI JTAPI Computer Telephony Integration Java Telephony Application Programming Interface What is a signaling protocol In a very simple sense all telephones perform two basic functions signaling and audio. When a user picks up a phone and hears the dial tone dials digits another phone rings put another on hold create a conference call this is signaling. When you talk on a phone to a person in a conference call or are leaving or hearing voice mail even hearing Music on Hold MOH this is audio. Traditional telephony prior to the exponential growth of VoIP performed signaling in either an analog or digital formats that still play an important role in voice gateways. While VoIP signaling protocols vary from vendor to vendor some proprietary others industry standard audio is handled by one industry standard IP protocol called Real Time Protocol RTP . Inside an RTP frame contains the digitized conversion of human analog voice created from codecs Coder-Decoder or Compress-Decompress . When bandwidth is abundantly available as in a LAN .