With the continuous development of computer technology and communication technology, network applications are penetrating into various fields of people’s social life.

Information appliances, as an important component of household informatization, are also entering people’s homes. However, there are still many problems that need to be solved urgently if information appliances want to develop in scale, such as the manufacturing level of infrastructure related to information appliances, the popularity of Internet infrastructure and the maturity of technology, as well as the development of information technology in the whole society, which have become factors restricting the development of the information appliance industry. The lack of information appliance industry standards has also become a bottleneck restricting the scale of information appliances. Incompatible equipment from various home appliance manufacturers will inevitably lead to redundant construction of the entire industry and waste of social resources.

As the core standard framework of NGN (Next Generation Network), IMS has created a new telecommunications business model and expanded the market space of the entire information industry. It is currently being highly praised by various telecommunications operators worldwide. IMS supports mobile and fixed intervention in design, organically combines mobile communication technology with Internet technology, and provides a standard framework for the construction of future information communication networks.

Therefore, building an IMS based information home appliance system is bound to become the trend of future development of information home appliances. 1MRK002133-ABr02 This article applies the Presence service based on IMS to information home appliance systems, establishes a home information home appliance system based on the increasingly perfect IMS network, and uses SIPPresence related standard protocols as the upper layer communication control protocol of information home appliances, facilitating the integration of various information home appliances into the IMS network, enabling information home appliances to directly adapt to the development of future 3G information networks. Meanwhile, directly deploying information home appliance systems using the Presence standard is beneficial for the standardization of the information home appliance industry and its integration with telecommunications systems.

2. Introduction to IMSPresence Business

Presence is a typical IMS based application proposed by IETF. Presence information is a message posted by Presences (users) to Watchers to indicate whether they are willing and possible to communicate. Through this method, users can inform their friends of their Presence status. Examples of basic Presence states include “online”, “busy”, and “away”. Nowadays, due to many users being constantly online, basic Presence information is no longer sufficient to meet their needs. The extended RichPresence (RPID) includes more information about users, their devices, and services, such as the most suitable communication method for users at the current moment, such as audio, video, or messages; The current location of the user; Contact information, etc.

Presence is implemented by PS (PresenceServer). PS provides event management functionality for user online information. PS collects user online information from the network layer.

The Presence protocol is used to exchange Presence information. IETF defines an extension of SIP (SIP/SIMPLE) to publish and order any type of information through the definition of event packets. According to the Presence practice package, Presence uses the PUBLISH method to send updated Presence information to PS, while Watcher uses the SUBSCRIBE and NOTIFY methods to receive updates to Presence information. The Presence model is shown in Figure 1.

 

Figure 1 IMS Presence Basic Model

3. Design and Implementation of Information Home Appliance System Based on Presence Business

From the introduction of IMS based Presence business above, 1MRK002133-ABr02 can understand that the current standardization and application model implementation of Presence have matured. Therefore, applying Presence business to information home appliance systems can not only adapt information home appliance systems to the future development of IMS networks, but also make it easier for information home appliance systems based on Presence to standardize and integrate information home appliances from various manufacturers.

The information home appliance system model based on Presence is shown in Figure 2.

 

In the Presence based information home appliance system, users can control the HA (Home Appliance) in the home network through HS (HomeServer) through a handheld terminal and IMS network. HS is integrated at the access point of the home network to the IMS network, and can be connected to various HAs using wired or WLAN.

HS collects the status information of various HAs in the home network and converts this information into Presence format information, which is sent as SIP messages to PS. PS treats the status information of HA as general presence information and promptly updates the information to the user terminal. For ease of explanation, simplify the system as shown in Figure 3. The entire system uses the SIP protocol as the upper control protocol, and directly uses SIP messages to achieve remote control and operation of information appliances.

 

3.1 Introduction to Each Functional Entity

3.1.1 Control terminals (UEs)

UEs are communication devices used by users for remote control, such as mobile phones, computers, etc. A typical embedded SIP terminal can complete UE functions. The characteristics of IMS networks that are independent of access methods provide UE with more flexible choices. Users can directly view the status of various household appliances through handheld devices and control operations when needed, as well as manage and control the behavior of various appliances through the Internet network.

3.1.2 servers

The server section includes two parts: PS and HS.

PS, also known as the Presence Server in the Presence business, is the application server (AS) deployed in the IMS architecture framework, which is the core of completing the Presence business. In terms of functionality, in addition to completing the original Presence application, it also bears the responsibility of interacting with HS. On the one hand, forwarding control commands sent by the user control end to HS, playing the role of RedirectServer; On the other hand, it receives status information from various household appliances from HS and promptly notifies users of status updates.

HS, a home server located in the user’s home network, is responsible for controlling various information appliances in the home network and playing the role of a home gateway. It is the core of implementing remote control of information appliances. On the one hand, HS receives and saves status information from various HAs, maps it to Presence status information, and sends SIPPUBLISH messages to PS to complete the function of collecting Presence information; On the other hand, by receiving control commands from the user control end through PS, the status changes of each HA are controlled. Compared to PS, HS plays a role as the source of Presence information in the system; Compared to HA, it plays the role of collecting and storing Presence information as a PS actor. Here, both PS and HS will save HA’s Presence information. The information on PS will be updated with HS.