Content Server
Distance learning is a boon to educational system. It connects each and every part of the world, making information accessible to anyone anywhere.
Content Server is a rack-mountable video conferencing network appliance used to capture audio/video or dual source from any H.323 video calls. H.323 is a protocol provides the audio/video visual communication. It is used to transfer the multimedia appliances over the internet. Content server can make point to point or multi point connections. It also provides an option to play the video live or Video on Demand (VoD) wherein video is played from archive.
Content server works more efficiently with Microsoft Windows than Quick play and real time. This is because the content server is based on the windows Enterprise Edition Server 2003. It also supports Multimedia Message service (MMS) and Real Time Streaming Protocol. Content server has internal storage device which can store up to 1200 hours of content at 384 kbps.
How Content Server works?
Video conferencing consists of both audio and video channel. H.239 provides rules and messages which helps in establishing the video and signal in H.239 and also provides the gateway between H.323 and H.239. In multi conferencing H.239 provides the token to guarantee that one source is sending the video channel which is distributed to multi users.
When H.323 is connected H.245 establish the set of all capabilities for all connected endpoints. After pinging with the server endpoint has to request a token from Multiple Control Unit (MCU). MCU will check with the other endpoint which currently sends additional video channel and uses the token ring to send the video from endpoint by sending the acknowledgement to the first endpoint.
H.323 has certain drawbacks which can be fulfilled by Session Initiation Protocol (SIP).
Session Initiation Protocol:
Session Initiation Protocol (SIP) is an application protocol used to create, modify and terminate the session with one participant. SIP is mainly used by VOIP to transfer the multimedia applications. It also supports both unicast and multicast streaming modes.
Advantages of SIP over H.323 protocol:
• H.323 is a group of protocols and very complex to install. SIP is more streamlined protocol developed specially for IP telephony.
• SIP can take control over the other protocols which cannot done by the H.323
• Call initiation and ending in SIP will be obtained by two communication tools helps to track the location of user.
• SIP can be easily updated like a HTML page
Content Server can work with both H.323 and SIP. SIP plays an important role in transferring multimedia applications and Data intensive web based applications.
Reference:
(2006). Tandberg content server and cisco acns networks. Retrieved September 22, 2007, Web site: http://www.tandberg.com/collateral/white_papers/Whitepaper_TANDBERG_Content_Server_and_Cisco_ACNS_Networks.pdf
(april 2006). White paper: advantage of sip for voip. Retrieved September 22, 2007, Web site: http://www.nokiaforbusiness.com/documents/WhitePaper_SIP_for_VoIP.pdf?doc=DL&ind=general