Robshaw's notable work includes the cryptanalysis of a number of cryptographic primitives, including the extension of linear cryptanalysis to use multiple approximations, and the design of the block ciphers Crab and RC6.
According to recent allegations made by Jacob Appelbaum, an independent computer security researcher, many NSA compromised systems appear to emit RC6 enciphered UDP traffic.
The ALP-44 based on the Rc6 model and designed specifically for New Jersey Transit as a variant of the EMD AEM-7 electric locomotive in use by Amtrak, MARC, and SEPTA.