The application of the Multi-stage Interconnection Networks (MINs) in Systems–on–Chip (SoC) and Application Specific Networks–on–Chip (NoC) is hottest since year 2002. Nevertheless, nobody used them practically for parallel communication. However, to overcome all the previous problems, a new method is proposed that uses MINs to provide intra (global) communication among NoCs in Networks–in–Package (NiP). For this, twin O(n^2)fault–tolerant parallel algorithms are proposed. It allows different NoCs to communicate in parallel using either fault–tolerant irregular Penta multi–stage interconnection network (PNN) or fault–tolerant regular Hexa multi–stage interconnection network (HXN). These two are acting as an Interconnects–on–Chip (IoC) in NiP. Both IoCs uses Wormhole Switching to route packets among NoCs. The results are compared in terms of packet losses and wormhole switching comes out to be better than packet switching.