Design And Implementation Of Presence And Im Mechanism For Mobile Internet

OTT services, represented by Presence/IM make it available for users to be realtime online and get access to communicate with others anywhere, became the era of mobile Internet hotspots and makes instant messaging applications obtain a rapid growth, from the perspective of communication protocols, these applications based on proprietary communication protocol development. In the current standards for telecommunications systems, Presence/IM mechanism is divided into two major categories of SIMPLE and XMPP, but these two kinds of protocols developed earlier, in terms of flow, power and transmission are not considering the characteristics of the mobile Internet. This paper relies on China Mobile ICT integrated server products(ICTII) actual demand, according to flow rate limited, low power mobile Internet terminal and network characteristics such as unreliable, was designed and implemented based on sub/pub model Presence/IM mechanism for the mobile Internet.First, analysis standard Presence/IM Protocol ——SIMPLE and XMPP, pointed out that there is a problem. Secondly, research the sub/pub model and MQTT protocol which based on sub/pub model, as a lightweight application layer transport protocol suitable for mobile Internet applications. Again, based on MQTT protocol, design topic and payload, completed the sub/pub model of the Presence/IM mechanism. Then, analysis ICT-II of business process and actual needs, using by design mechanism as bottom communications mechanism, design has rates communications mechanism server of overall schema, main including MQTT broker, and basic Presence, and system IM Log, and more Terminal news synchronization, and pre subscription, and unified message center several module, and using Linux and C, based on open source implementations of MQTT——Mosquitto, gives an implementation. Finally, according to a functional and performance testing, this communication mechanism compared with the SIMPLE and XMPP.