Fast channel change handling of late multicast join
US8161515B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 13, 2009 |
| Grant date | Apr 17, 2012 |
| Priority date | — |
| Expiry date | Jan 22, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N21/6405
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In an internet protocol television (IPTV) system, fast channel change (FCC) transactions that experience late multicast joins are handled specially, thereby allowing the system to be provisioned for the vast majority of multicast joins that are within an expected range. During an FCC transaction, the subscriber interface device, such as a set-top box (STB), can determine how long it can wait to join the multicast stream of the new channel before a gap can be predicted to occur in the handover from the FCC unicast to the multicast. If the STB has not joined the multicast stream by the determined time, a recovery procedure is invoked in which the STB sends a RESTART request to the FCC server which, in turn, increases the rate of the FCC unicast as if the FCC transaction were restarted, thus allowing the handover to occur seamlessly. This solution reduces the demands of each FCC transaction, allowing for greater scalability and reduced cost.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.