Different implementation of network level in embedded networking with QoS

Some modern standards in space industry, which are being used in embedded networking designs, provide quality of service features, which are implemented by means of virtual channels. Implementations of virtual channels mechanisms are very different. Each implementation has its latency characteristics for packet flow, hardware cost and performance. These parameters depend on the virtual channels quantity in a port and switch matrix's channels quantity connected to every port (connection point). The connection point quantity can vary from one to a number of virtual channels in port. We consider three structures and implementations of network layer. In the first implementation quantity of connection points is equal to number of virtual channels in a port. In the second - one connection point. The third - one connection point with lower priority data transmission interruption. In this article we compare characteristics of different architecture implementations and structures of port controllers and switch matrix. Also we analyze and simulate proposed mechanism. We present formulas to calculate minimum and maximum data packet transmission latency and compare theoretic and simulation results. Count of virtual channels is 4 for simulation, packet length - 250, 750 bytes. Moreover router's switch matrix hardware cost is evaluated in the article.