ArtsAutosBooksBusinessEducationEntertainmentFamilyFashionFoodGamesGenderHealthHolidaysHomeHubPagesPersonal FinancePetsPoliticsReligionSportsTechnologyTravel

VoIP Tele Phone Service - Interaction with H.323 protocol

Updated on September 29, 2011

Since the beginning of use of Voice over IP services, it was basically decided to use h.323 as the basis of VoIP; therefore, VoIP or Voice over IP is seen as a clarification of h.323 protocol making sure that in order to avoid some differences between standards and in case of conflicts, it was decided since the past that priority would be always given to h.323 on VoIP. VoIP or Voice over IP services have focused on ensuring interoperability between VoIP devices from different types of manufacturers for example fixing issues with voice routing and coding, silence suppression, and setting up new elements to enable connectivity to traditional telephone system. These elements are concerned with transmission of dual-tone multi-frequency or in simple abbreviated form DTMF.

H.323 protocol is used for making IP calls with NetMeeting, etc. The H.323 protocol allows us a many types of interacting elements, which include:

Terminals are the users who take the first step in using a VoIP connection. Users or terminals are only able to connect with each other and if additional user access is required for communication, this needs incorporation of some additional elements namely gatekeepers which operate as follows:

  1. Address Translation Services like DNS or Domain Name System so that the user is able to use names instead of IP addresses.
  2. Admission control and authentication to deny and allow user access plus managing bandwidth.
  3. Gateways points of reference for conversion TCP/IP - PSTN.
  4. MCUs or Multipoint Control Units to allow holding of a conference.

H.323 is not only used for Voice over IP, but is also used for exchange of video and data communication. H.323 includes a set of standards and is basically supported by series of protocols which cover different configurations of communication:

For Address:

Registration, admission and status or RAS is a communication protocol, which allows one h.323 station to locate another h.323 station via the gatekeeper.

Domain name system or DNS is a service through which the Internet domain names are located and then translated into IP addresses. The DNS serves the same purpose as the RAS protocol but it is done via a DNS server and not a gatekeeper.

For Markings:

Initially requires Q.931 for call signaling.

H.225 protocol is required for call control, i.e., call signaling and call setup, registration and admissions, and synchronization/ packetization of the flow of voice.

H.245 protocol controls messages to specify closing and opening of channels for voice flows.

Voice Compression:

Requires: G.711 and G.723

Optional: G.728, G.729 and G.722

Voice Transmission:

User Datagram Protocol or UDP: Transmission of voice takes place on UDP voice packets, but the UDP cannot provide data integrity, as use of bandwidth while using UDP is higher than TCP.

Real time protocol or RTP manages aspects of scoring and timing of UDP packets with the necessary information for efficient delivery of packets to the reception.

Transmission Control:

Real time control protocol or RTCP is used for detecting situations of network congestion and it takes appropriate corrective actions wherever necessary.

VoIP application is built by different number of elements already available in the market and these are:

  • IP Phones
  • Adapters for personal computers
  • Telephone hubs.
  • Gateways like PSTN/IP
  • Gatekeeper
  • Multiple control units or audio units
  • Directory services

Comments

    0 of 8192 characters used
    Post Comment

    • soni2006 profile imageAUTHOR

      Rajinder Soni 

      8 years ago from New Delhi, India

      Thanks a lot Veronica. It look long time to publish this one.

    • Veronica Allen profile image

      Veronica Allen 

      8 years ago from Georgia

      Very detailed.

    • soni2006 profile imageAUTHOR

      Rajinder Soni 

      8 years ago from New Delhi, India

      Thanks a lot Mr. Roychoudhury. It took me a lot of time in learning and then preparing about this info, but I admit I am getting a lot of help.

    • H P Roychoudhury profile image

      H P Roychoudhury 

      8 years ago from Guwahati, India

      Information is undoubtly good but technical.

    working

    This website uses cookies

    As a user in the EEA, your approval is needed on a few things. To provide a better website experience, hubpages.com uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

    For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at: https://hubpages.com/privacy-policy#gdpr

    Show Details
    Necessary
    HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
    LoginThis is necessary to sign in to the HubPages Service.
    Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
    AkismetThis is used to detect comment spam. (Privacy Policy)
    HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
    HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
    Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
    CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
    Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the googleapis.com or gstatic.com domains, for performance and efficiency reasons. (Privacy Policy)
    Features
    Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
    Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
    Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
    Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
    Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
    VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
    PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
    Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
    MavenThis supports the Maven widget and search functionality. (Privacy Policy)
    Marketing
    Google AdSenseThis is an ad network. (Privacy Policy)
    Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
    Index ExchangeThis is an ad network. (Privacy Policy)
    SovrnThis is an ad network. (Privacy Policy)
    Facebook AdsThis is an ad network. (Privacy Policy)
    Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
    AppNexusThis is an ad network. (Privacy Policy)
    OpenxThis is an ad network. (Privacy Policy)
    Rubicon ProjectThis is an ad network. (Privacy Policy)
    TripleLiftThis is an ad network. (Privacy Policy)
    Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
    Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
    Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
    Statistics
    Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
    ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
    Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)