The "user permit" of ENC charts is a unique identifying number attached to a device, or to an application, able to read encrypted ENC chart data (format S-63). This “User Permit” is required to register a system (chartplotter, MFD, software) and thus make it possible to generate, for charts purchased, a single authentication code to use these charts to the referenced system. User Permit (User Permit) consists of a chain of 28 digits hexadecimal code.
Let's take the example of a purchase on the site Chartworld. Read more …


