Many US Government agencies and organizations use ISC open source software. We offer technical support services, including DNS audits. As the author, maintainer and publisher of BIND, ISC DHCP and Kea, we are the sole source that is capable of performing some of these services.
Below please see ISC’s Capability Statement.
References pertaining specifically to US Government open source users:
Network Infrastructure Security Technical Implementation (STIG) Overview, 2 January 2019 (note discussion of IP Addressing approaches)
Domain Name System (DNS) Security Requirements Guide (SRG) 10/23/2015
DoD Open Source Software (OSS) FAQ web page
“Open source software that has at least one non-governmental use, and has been or is available to the public, is commercial software. If it is already available to the public and is used unchanged, it is usually COTS.”
Bind DNS STIG, Version 4, release 1.19, October 23, 2015
Google Group (mailing list) for Military Open Source Software
ISC’s Capability Statement