## 1 Introduction  
Cooperative communication refers to selecting multiple forwarding nodes for cooperative communication when forwarding data, which can improve the reliability of transmission; intelligent mobile agent can collect data in the network, and integrate, compress and encrypt data at the same time, which provides additional flexibility and new functions for the Internet of things network layer. Cooperative communication needs to consider various energy saving measures. In high dynamic networks, saving energy while maintaining the reliability of nodes is an important research direction. Although multiple forwarding nodes are used in existing cooperative communication protocols to improve the reliability of nodes. The reliability model is unpredictable. Moreover, using the sleep of the sensing node to save energy is not considered. Therefore, a new cooperative communication algorithm is needed. Multi-agent routing planning is a new research direction of intelligent agent transmission. The multi-agent routing is prone to overlap between routes, which results in energy waste. Furthermore, it is necessary to study new multi-agent routing algorithms.  
In recent years, wireless sensor networks (WSNs) are an important part of the Internet of Things (IoT). They have undergone tremendous development [1]. The wireless channel of WSN in the IoT changes dynamically and the resources of nodes are limited. Thus, it is a great challenge to provide high-performance communication, especially multimedia communication. Cooperative communication is considered a solution to this challenge, which is scalable, energy efficient and fault tolerant [2; 3]. The IoT has been applied to various fields and formed intelligence. WSN is the network layer of the IoT. Through intelligent mobile agents, data and deploy tasks can be collected. The optimization algorithms of cooperative communication and intelligent mobile agent are studied. The specific contributions are as follows.  
1. In the aspect of cooperative communication technology, a new cooperative communication algorithm KCN (k-cooperative node) is proposed. K cooperative nodes for transmission are used in each hop. Moreover, the reliability of transmission in dynamic network is improved.
2. Intelligent mobile agent has a view of the whole network. Sink node centralizes the planning of proxy routing. The proxy routing can be controlled by programming. In fact, the idea of software defining network has been applied in the realization of an intelligent agent. In this paper, the multi-agent routing planning algorithm is studied, and a directional source grouping based multi-agent itinerary planning (D-MIP) is proposed.  
The remainder of the paper is structured as follows. Section 2 introduces the current research progress and shortcomings. In Section 3, a new cooperative communication algorithm KCN is proposed. The algorithm uses K cooperative nodes per hop for transmission, which improves the reliability of transmission in dynamic network. Section 4 studies the multi-agent routing planning algorithm and proposes the directed source packet multi-agent routing planning algorithm. Section 5 describes the experimental process and result analysis. Section 6 summarizes the whole paper and puts forward the next research plan.