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use dtv cookies

In the DTV system, persistent client-side cookies are stored locally on the STB and backed up in a database on Liberate’s User Data Server (UDS) roughly every 2 minutes. Cookies work in a very similar way as they would be used on a PC Internet site.

DTV client will store locally a maximum of 30 x 4kb cookies per STB. Where some cookies are greater than 4Kb in size, the total number will reduce accordingly. The User Data Server (stores persistent cookies) will store a maximum of 100 cookies per STB.

Please see the Liberate CDK for further information on using cookies

Developers should be aware of the following when writing Cookies

  • When the available space is filled, cookies will be deleted on a "First In First Out" criteria. This is based on when the cookie was last used NOT when it was originally saved.
  • Liberate developed JS extensions for Cookies "Cookie Objects". Each object represents 1 cookie and has a set of properties (name, value, path etc) which define the cookie.
  • Developers must use Liberate’s plural syntax "document.cookies" (an array which calls the Cookie objects), NOT the standard Javascript syntax "document.cookie".
  • To ensure a cookie is persistent (i.e. saved in the UDS) you must set an expiry date/time, and you must use the Liberate code extension "store".
  • Secure cookies can't be read from an insecure page.
  • Don’t mix IP addresses and domain names when using cookies
  • The session will close when the user exits the site

Last updated: 30 Sept 2002

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requirements
caching
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   © ntl Group Ltd 2002