UPnP Eventing with Multicast Support in Home Computing Network

The UPnP technology is widely employed to enable networked devices interconnected in home computing environments. Its UPnP eventing protocol is on the base of HTTP over TCP in a unicast fashion. However, unicasting event notifications may suffer from scalability problem and performance degradation against either high device mobility or highly frequent updates of service states. To mitigate above circumstances, we propose in this paper an event multicast mechanism to sustain dynamic nature of device mobility and service state changes. The devised mechanism can group service subscribers of the same access interest and respond a group-specific subscription identifier and a shared event key to every subscriber in a group. Subscribers can be later notified of events synchronously through listening on a specific administratively scoped multicast address. The design of this mechanism is compliable with GENA specification, so being able to coexist with the current UPnP eventing method. The experimental prototype further shows that this design is lightweight and does not complicate the UPnP system design.