In the near future, the packet switching system will need a large switching capacity. But, large processor can not be obtained in cheap way. So, it seems better to use smaller processors in a distributed fashion to obtain a large switching capacity. If several small switching devices are interconnected, it will be possible to increase the traffic handling capacity. Depending on the topology of the network, overall processing characteristics are different. Switching networks like torus etc. have the problem, because their nodes have the transit traffic. According to the increase of the switching network size, the transit traffic becomes large and the overall traffic efficiency of the network decreases significantly. The mesh network, in which all nodes are interconnected, does not have that problem, because there is no transit traffic in any node. This paper describes the composition of mesh type distributed packet switching systems. Flexible architectures are proposed, which are based on the building block structure. A node of these architectures is composed of several switching elements, and one or two intranode switches. Using these architectures, the addition of a new node to the system can be done without any modification of the fundamental units. The experimental system has been designed and built.