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-appengine-python-13.0-wheezy-amd64.iso.sig gpg: Signature made Tue Oct 15 14:47:14 UTC 2013 using RSA key ID A16EB94D gpg: Good signature from "Turnkey Linux Release Key" For your convenience we also include file checksums: * sha1sum 9f496870a7c274e0be3c1f92aaa8a0274a40e16d * md5sum 5602b8b919404441642671fae490a951 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 v1.4.12 (GNU/Linux) iQEcBAABAgAGBQJSXVVpAAoJEIXCXpWhbrlN7bAH/im4U8EEajvzNiBHnzs+Nfu+ d9Ze1tv6LSfgtmW52lOMEiCSvOj+k0woVRG2/x6T7NW8YPvdodVirbLfuPSI8sav 7Yf72+GIfzsUIY3XQj45vHsPucTGwXubDPiF/jL0QzNIAhvOU0rQvR5Eezcg6lnT 7P9IjzTYNaGWQmfTR7DjfTOumjCRl3ByAC4jIrNmBszasDnvmJMtygacpu1iDozs lYHPDaur6WYCRkF6/JgYkd5xDZnt7ag+rx53/yaD/RgJBbi+iAOvWmS5Q/9WXLEP UKjp3fv7mfUcL3+IO6mAjqpb8blqcR0+0+e9ybGf1gHeoluCTQY50xghW7IOfUw= =rXcY -----END PGP SIGNATURE-----