The Trusted QSL SDK has been created with the concept that there should be a secure and trusted way to exchange E-QSL cards. To this end TQSL library and tools was created. Too avoid any one entity from having control over this powerful system, the sources for all the libraries and tools are release under the GNU Lessor GNU Public License or (LGPL) In short is says that your can do anything your want with the source provided you don't try to prevent others from doing the same. The design goals for this product was fairly simple:

### Goals

- Secure - At least 700 bits
  1. Authentication - Must be able to for the receiver of a message to ascertain its origin.
  2. Integrity - Must be able to verify that the message hasn't been changed or substituted.
  3. Nonrepudiation - A sender should not be able to falsely deny later that he sent a message
- Programmer Friendly - Easy to add existing program
- Portable - Source should compile just about any OS
- User Friendly - Should be easy for CAs and end users.

### Installation

1. First your must get and compile OpenSSL
2. Build the TrustedQSL library. On Linux you can use the Makefile.
3. Build example command line program.
4. Test example program tqverify with command tqverify -f README -s README.sig