This signature file may be used to cryptographically verify file integrity, like this:: $ gpg --keyserver hkp://keyserver.ubuntu.com --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-drupal6-12.1-squeeze-i386.iso.sig gpg: Signature made Thu Apr 18 13:30:43 UTC 2013 using RSA key ID A16EB94D gpg: Good signature from "Turnkey Linux Release Key" For your convenience we also include file checksums: * sha1sum 494c1ae087cc54766cafa9da686fd77e18d95e3d * md5sum eaa54f1066d29038e51e556190c694c4 You can calculate these on your end and compare to check for errors, but cryptographic verification is recommended for security reasons. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) iQEcBAABAgAGBQJRb/VjAAoJEIXCXpWhbrlNB3AIAIqoYj2/X8yrhaONSTXSaxd9 wdjqtXVKBF/JHt3JgVC1h4iQfme7MD3OaExA5BupJIBG3mum1sJV99pVUu9tfAoX XDRODUrkiy1vQEVB+D1qeNXFSt09E+3eF/1oxgNGKW51hwYwnEmzr8QQa8+4DZPv Kc48XcUZBIHhDnsQiNO6D3T2rfn65Y7YhyHHAwFvMd1hes4c/tf9pmKSPMzzZi7r aeST8WAWk7f/T3/xqHSylgwpZCMWDldZ1ykXn8hwaosEP4FSZxzNvsMF7Aca227i FiAoebWAriwTTGXtb92XOj09Ors6UFX3Ic1GYvbYDT4SdNdFDatmIxPhxZmZkr4= =XQMd -----END PGP SIGNATURE-----