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-java-13.0rc2-wheezy-amd64.iso.sig gpg: Signature made Wed Aug 7 07:33:13 UTC 2013 using RSA key ID A16EB94D gpg: Good signature from "Turnkey Linux Release Key" For your convenience we also include file checksums: * sha1sum 52b446a77f17d5469a92297ff09a0a2b4dbe6d3b * md5sum 71329ec711109691a4af0158091b86c6 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) iQEcBAABAgAGBQJSAfgqAAoJEIXCXpWhbrlNId4H/0Q1lqPPzGXkdToLUM5KHhMt 4Ht2FcPUgwVPYVQBrJ5ahK6XjJ1Jy/LwG+DoAcaocRrfOw8NeMqXBVqXyMVvWaU8 ZFbVYIhHlv1ZQaNWQDYXklgU+iiDnj2dOJsw91PN2SAKffHqJDlG97NrggOQWvaa X+yosTeI0OIIhjvOM0/21XUtXODuN+GRll4VqW+pc0dV6CAdJPjhyDTCLiFI0cx/ 6GB3HscB0P1lDG0LLBrx9eGXvMYF3b1WV1vLCAbV79rl+DoWSw20xa1nw2bYIPPY S97sqyl/ulVfqwDFdjZJ/8If3+pp0aYSPfspUsHdB/O8R2WRsIXH1kgoxZLmYS4= =FE3B -----END PGP SIGNATURE-----