Falcot 公司的管理极重视安全。因此，他们只安装 Debian 保证无窜改的软件包。电脑怪客可能在合法的软件包巾加入若干恶意代码。若安装了这种软件包，就会运行怪客要它做的事，包括泄露密码或隐私信息。为避过这个风险，Debian 有个机制在安装时避过此纂改的风险，只安装来自官方维护者的软件包且未经第三方修改。
以一连串的密码学哈希与签章构成密封的作品。签章文件是由 Debian 镜射站提供的 发布 文件。包括 软件包 文件清单 (包括压缩格式的 软件包名称.gz 与 软件包名称.xz，以及增量版)，与它们的 MD5、SHA1 与 SHA256 哈希，确保文件不曾被篡改。这些 软件包 文件包括镜射站提供的 Debian 软件包清单，以及其哈希，足以保证软件包内容不曾被篡改。
APT needs a set of trusted GnuPG public keys to verify signatures in the Release.gpg files available on the mirrors. It gets them from files in /etc/apt/trusted.gpg.d/ and from the /etc/apt/trusted.gpg keyring (managed by the apt-key command). The official Debian keys are provided and kept up-to-date by the debian-archive-keyring package which puts them in /etc/apt/trusted.gpg.d/. Note however that the first installation of this particular package requires caution: even if the package is signed like any other, the signature cannot be verified externally. Cautious administrators should therefore check the fingerprints of imported keys before trusting them to install new packages:
# apt-key fingerprint
/etc/apt/trusted.gpg.d/debian-archive-jessie-automatic.gpg
----------------------------------------------------------
pub rsa4096 2014-11-21 [SC] [expires: 2022-11-19]
126C 0D24 BD8A 2942 CC7D F8AC 7638 D044 2B90 D010
uid [ unknown] Debian Archive Automatic Signing Key (8/jessie) <ftpmaster@debian.org>
/etc/apt/trusted.gpg.d/debian-archive-jessie-security-automatic.gpg
-------------------------------------------------------------------
pub rsa4096 2014-11-21 [SC] [expires: 2022-11-19]
D211 6914 1CEC D440 F2EB 8DDA 9D6D 8F6B C857 C906
uid [ unknown] Debian Security Archive Automatic Signing Key (8/jessie) <ftpmaster@debian.org>
/etc/apt/trusted.gpg.d/debian-archive-jessie-stable.gpg
-------------------------------------------------------
pub rsa4096 2013-08-17 [SC] [expires: 2021-08-15]
75DD C3C4 A499 F1A1 8CB5 F3C8 CBF8 D6FD 518E 17E1
uid [ unknown] Jessie Stable Release Key <debian-release@lists.debian.org>
/etc/apt/trusted.gpg.d/debian-archive-stretch-automatic.gpg
-----------------------------------------------------------
pub rsa4096 2017-05-22 [SC] [expires: 2025-05-20]
E1CF 20DD FFE4 B89E 8026 58F1 E0B1 1894 F66A EC98
uid [ unknown] Debian Archive Automatic Signing Key (9/stretch) <ftpmaster@debian.org>
sub rsa4096 2017-05-22 [S] [expires: 2025-05-20]
/etc/apt/trusted.gpg.d/debian-archive-stretch-security-automatic.gpg
--------------------------------------------------------------------
pub rsa4096 2017-05-22 [SC] [expires: 2025-05-20]
6ED6 F5CB 5FA6 FB2F 460A E88E EDA0 D238 8AE2 2BA9
uid [ unknown] Debian Security Archive Automatic Signing Key (9/stretch) <ftpmaster@debian.org>
sub rsa4096 2017-05-22 [S] [expires: 2025-05-20]
/etc/apt/trusted.gpg.d/debian-archive-stretch-stable.gpg
--------------------------------------------------------
pub rsa4096 2017-05-20 [SC] [expires: 2025-05-18]
067E 3C45 6BAE 240A CEE8 8F6F EF0F 382A 1A7B 6500
uid [ unknown] Debian Stable Release Key (9/stretch) <debian-release@lists.debian.org>
/etc/apt/trusted.gpg.d/debian-archive-wheezy-automatic.gpg
----------------------------------------------------------
pub rsa4096 2012-04-27 [SC] [expires: 2020-04-25]
A1BD 8E9D 78F7 FE5C 3E65 D8AF 8B48 AD62 4692 5553
uid [ unknown] Debian Archive Automatic Signing Key (7.0/wheezy) <ftpmaster@debian.org>
/etc/apt/trusted.gpg.d/debian-archive-wheezy-stable.gpg
-------------------------------------------------------
pub rsa4096 2012-05-08 [SC] [expires: 2019-05-07]
ED6D 6527 1AAC F0FF 15D1 2303 6FB2 A1C2 65FF B764
uid [ unknown] Wheezy Stable Release Key <debian-release@lists.debian.org>
适当的钥纳入钥匙圈后，APT 将检查签章后才会运行任何危险的操作，若要求安装的软件包其认证不明确时，前端将出现警示消息。
