Summary

Each computer that runs applications that use ENCX is licensed using a hardware dongle. You buy the dongle from us.

Uniquely associated with that dongle is a code called the user permit. We send you that in an email when you buy a dongle.

When you buy commercial chart data you send the chart seller user permit for your dongle. They create chart permits which allow you to install the charts with that particular dongle.

The chart supplier sends you the charts and the chart permits. You install these into your ENCX application.

Detailed Explanation

Commercial ENC (S-57) and the UKHO ARCS licensing systems work in a very similar way. They key to this is a code (UID) which is unique to each User and which cannot be copied. Usually this is held in a hardware device such as a dongle however other techniques are possible.

Associated with each UID is a User Permit. This is an encrypted string which contains the UID and additional information. Each User is given a User Permit when they purchase their Navigation System. The User Permit does not change.

The User Permit is passed to a Chart Supplier (such as the UKHO) who can use it to create Chart Permits. Each chart is encrypted and the chart decryption key is encrypted using the UID. There is one Chart Permit for each chart. The Chart Permit is specific to a particular User.

The ENCX can now access the supplied charts as follows:

• Read the UID from the dongle.
• Use the UID to decrypt the Chart Permit.
• Use the decrypted Chart Permit to decrypt the chart.

So each User gets a unique User Permit which is associated with a unique dongle. When they purchase charts they are issued unique Chart Permits which only their system can use to actually view the charts.

(If you only want to use unlicensed ENCs you might want to look at ENCX UDE)

Dongles

Licensing dongles are small USB devices similar in size to the "memory sticks" that many people use.

You can move dongles around from computer to computer.

Charts are licensed to a particular dongle. If you have a system where two computers are installed on one vessel the dongles can be identical "clones" of each other. That way you only pay one set of chart licensing fees. The second dongle can be used as a backup in the event of mechanical damage to the primary system.

If you want data from the United Kingdom Hydrographic Office (UKHO) we can resell that to you and handle all the licensing details.