-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Two steps are required to cryptographically verify image integrity. 1. By verifying the integrity of this signature file, you can be sure that the checksums included in this file are valid. $ gpg --keyserver hkp://pool.sks-keyservers.net --recv-keys 0xA16EB94D $ gpg --list-keys 0xA16EB94D pub 2048R/A16EB94D 2008-08-15 [expires: 2023-08-12] uid Turnkey Linux Release Key $ gpg --verify turnkey-moodle-14.1-jessie-amd64.iso.sig gpg: Good signature from "Turnkey Linux Release Key" 2. By calculating the image checksum and validating the hashed value is the same as listed below, you can be sure the image was not corrupted in transit or tampered with. $ md5sum turnkey-moodle-14.1-jessie-amd64.iso 87baa137d862a72a481ecb938138386a $ sha1sum turnkey-moodle-14.1-jessie-amd64.iso af4042caab003e08b1debf13347d0d8ece86487b -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQEcBAEBAgAGBQJXCkPyAAoJEIXCXpWhbrlN0UMIAMicY9hh2iB1OH/qNOiWSrJt iq617OQTW7CUNBIzIh3cEvBMFRypzajqL7NLgBzN0ZZXqdytt64hCBwtrylAF5Im bqzMF4yFrvomdzdvoQePnMHuA2Vs4u6aPqNZ/kxeLDnCf28uOr1wrxB78BgYQ2Hp DXJ4rqHd73EomAzpPMuqOchWCvKI6qnHqz4is0XlK+HfW/WZhlYqhtcWOOMSEaJ7 3zRTPLsdERh095Qu3Zb5LXceQYAz/4711GAvN6HNUb1O3eSxa6wj5GzvUJ3MqtSR 9FfKtdyicoTylAs1bQuby9qfy9sruAQf3XeM9QSOcq81LkwUhijskh/j7VPkV0s= =Ph/a -----END PGP SIGNATURE-----