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-13.0-wheezy-i386-vmdk.zip.sig gpg: Signature made Tue Oct 15 14:56:52 UTC 2013 using RSA key ID A16EB94D gpg: Good signature from "Turnkey Linux Release Key" For your convenience we also include file checksums: * sha1sum 8a7ecae37592abd70ed18f8df51b70f6968683d7 * md5sum 9703226d1aaf704280ab245ce468d09a 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) iQEcBAABAgAGBQJSXVehAAoJEIXCXpWhbrlNxXcH/A5LlTy5nlJH41LyPaVYjOiH lxeB8QmUEBRMs93wJAyUsHj/NAK/KAGKVy88KfP2bT/2m4vEX99ysYlnHifyPW8C Q6dZeq32n5ZTgrTJCUnkU+PNOQwYypmgAZdbZYEECGJ7U1K8W7WhAuyR5csqyE2i dW2/hKtMgjh9yuOZydyCFUo53k27RS3r/igFs6+2/QF+6onS+vp+wq6Ipo970kV6 Y1/X4WP03mvxHP8M6YEsaTzmFmr3jjOViluIkgsZkYRaqZZfwqf5M+tXj1LNzV5D GPyVNg3K6RN+8MK3H8qU2ukp0PBAPBHg0+7bRZEFV/CSDewnZayg+b8l7mB67hE= =ibzL -----END PGP SIGNATURE-----