X.75

X.75 is an International Telecommunication Union (ITU) (formerly CCITT) standard specifying the interface for interconnecting two X.25 networks. X.75 is almost identical to X.25. The significant difference is that while X.25 specifies the interface between a subscriber (Data Terminal Equipment (DTE)) and the network (Data Circuit-terminating Equipment (DCE)), X.75 specifies the interface between two networks (Signalling Terminal Equipment (STE)), and refers to these two STE as STE-X and STE-Y. This gives rise to some subtle differences in the protocol compared with X.25. For example, X.25 only allows network-generated reset and clearing causes to be passed from the network (DCE) to the subscriber (DTE), and not the other way around since the subscriber is not a network. However, at the interconnection of two X.25 networks, either network might reset or clear an X.25 call, so X.75 allows network-generated reset and clearing causes to be passed in either direction.

The Triumph X-75 Hurricane was a 'factory special' motorcycle designed by fairing specialist Craig Vetter. The X-75 had swooping glassfibre bodywork, a three US-gallon petrol tank, lowered gearing and a distinctive triple exhaust on the right-hand side. The motorcycle is credited with creating a new class of motorcycle, the cruiser.