The signature will have the following format:
mm: is a two letter code denoting the maker of the tool
tttt: is a two to four letter code denoting the name of the tool
vv: is a two digit code indicating the major and minor version of the tool
For example, the survey tool produced by lams has a signature of lasurv10. The "la" indicates that it was developed by the main LAMS team, "surv" stands for "survey" and "10" indicates that it is version 1.0.