I am trying to set up Ubuntu with full disk encryption, by following this tutorial over here.
What I want to know is what encryption module does Ubuntu use to encrypt the data ? Is it LUKS ? If not how does the encryption module that it uses compare to LUKS ?
The encrypion module is LUKS.
The Linux Unified Key Setup or LUKS is a disk encryption specification created by Clemens Fruhwirth in 2004 and originally intended for Linux.
While most disk encryption software implements different and incompatible, undocumented formats, LUKS specifies a platform-independent standard on-disk format for use in various tools. This not only facilitates compatibility and interoperability among different programs, but also assures that they all implement password management in a secure and documented manner.
The reference implementation for LUKS operates on Linux and is based on an enhanced version of cryptsetup, using dm-crypt as the disk encryption backend.
LUKS Design:
LUKS is the standard for Linux hard disk encryption. By providing a standard on-disk-format, it does not only facilitate compatibility among distributions, but also provides secure management of multiple user passwords. In contrast to existing solution, LUKS stores all setup necessary setup information in the partition header, enabling the user to transport or migrate his data seamlessly.
Source:
https://gitlab.com/cryptsetup/cryptsetup/blob/master/README.md
https://en.wikipedia.org/wiki/Linux_Unified_Key_Setup