Using geo-spatial session tagging for smart multicast session discovery

IP multicast is increasingly seen as efficient mode of live content distribution in the Internet to significantly large subscriber bases. Despite its numerous benefits over IP unicast, multicast has not seen widespread deployment over modern networks. Network complexity and session discovery issues have plagued IP multicast since its inception. The Internet research community is in general agreement to move over to SSM (Source Specific Multicast).

With IGMP v 3 (Internet Group Management Protocol) and SSM, the source discovery burden will rest with the end user. Channel discovery is one of the few stumbling blocks remaining to be solved for successful and widespread deployment of multicast. In an earlier work a DNS (Domain Name System) aware multicast session discovery architecture, mDNS, has been proposed which is distributed, hierarchical and globally scalable.

This paper proposes to leverage the mDNS architecture by enabling multicast sessions to be tagged using geographical and spatial information based on the channel contents or service provider location. It further proposes automatic geo-coding of session registration information as the content provider registers session information with mDNS. It also provides necessary design changes and gives data models and data structures to support seamless location sensitive session retrieval as part of search query results to be furnished to the end user. The paper includes envisaged scenarios in which geo-tagging would enhance end user experience and would enable smarter query result generation.