| 摘要 |
A scalable messaging framework (100) that allows applications to send and manage announcements in an IP network is described. In particular, the messaging framework (100) provides for the end-end delivery of announcements and files over multicast and unicast. Announcements may refer to file updates, messages, commands etc. The format of the event description in the announcement is described by an extensible format called EventMetadata. Announcements can be pushed to the receiving devices (104) using multicast or unicast push mechanisms or downloaded by the receiving devices using unicast poll-pull mechanisms. When using push mechanisms, the announcements are repeatedly sent to all the receiving devices as long as the corresponding event is active to increase the chances of delivery to all receiving devices. When using polling mechanism, the receiving devices poll Messaging framework at intervals determined by Messaging framework on a per receiving device basis to retrieve a list of new announcements since last poll |
