Accessing networked appliances using the session initiation protocol

This document proposes the use of SIP for Network-capable appliances. It leverages standard SIP capabilities to directly communicate with appliances even when they are behind firewalls, NATs or other entities that prevent direct end-to-end communication. When combined with the recently proposed Instant Messaging and Presence SIP extensions these techniques become even more powerful to allow the secure and reliable access to appliances in a variety of different networked environments. 1 INTRODUCTION The next wave of the Internet is widely predicted to be the move towards the Networked Appliance (NA); The refrigerator that can keep an inventory of your groceries and reorder when necessary or perhaps the alarm clock that can coordinate your agenda, the weather and the road conditions to determine the correct time to wake you up. It is clear that these appliances will need to communicate amongst themselves so that, for example, the alarm clock can turn on the bedroom lamp, but the mechanism these appliances will use to communicate is far from obvious. This document provides the rationale behind the requirement for the standardization of these mechanisms and proposes extensions to the SIP architecture to meet these requirements. It further presents ways in which these new mechanisms are intended to be used. Networked Appliances (NAs) are dedicated function consumer devices containing at least one networked processor. Examples include lamps, coffee makers and alarm clocks. Figure 1 provides an example of a home domain containing Networked Appliances, with a SIP Proxy providing access across the firewall. Appliances within a single home are not intended to use the capabilities outlined within this document for communication between themselves, but it is important to have a conceptual understanding of the in-home communication techniques that are being developed in order to understand the relationship of this document to them. For the purposes of this document, a home is considered to be a single (DNS) domain. Inter-device communication within a single domain can be subdivided into two essential issues; the location and identification of the device it is desired to talk to and then the communication with it. Some approaches separate these two issues explicitly although most tend to merge them into a single solution. There are numerous emerging standards for in-home inter-device communication (HAVi[3], VESA [6], JINI[5] and UPnP[2] being four obvious examples) and there are other standards explicitly dedicated to location and identification of services (SLP[13] and Salutation[4] for example). There …