Fill Device

Primary definition

A COMSEC item used to transfer or store key in electronic form or to insert key into KYK-13, and KYK-15. cryptographic equipment. The "Common Fill Devices" are the Electronic fill devices include, but are not limited to, the DTD, SKL, SDS, and RASKI. Source: CNSSI No. 4005 (COMSEC)

Also known asCommon Fill Device · Electronic Fill Device · CFD · EFD
2 sources cited4 related termsReviewed Aug 9, 2026
Committee on National Security Systems Glossary CNSSI 4009-2015View source
People also ask

What is fill device?

The term Fill Device refers to a COMSEC device used to store, transfer, or insert cryptographic keying material into cryptographic equipment, including legacy common fill devices and newer electronic key loaders. It gives election, security, legal, or technical readers a specific label for the concept rather than a broader everyday meaning.

How is fill device used in cryptography or COMSEC?

In practice, Fill Device is applied to the technical or security purpose captured by its definition: a COMSEC device used to store, transfer, or insert cryptographic keying material into cryptographic equipment. Organizations combine that function with documented procedures, authorized access, testing, monitoring, and controls appropriate to the system. The governing standard or security policy determines the exact implementation.

Why does fill device need security controls?

Understanding Fill Device matters because the concept can affect security, reliability, auditability, or trusted operation. In this glossary context, it refers to a COMSEC device used to store, transfer, or insert cryptographic keying material into cryptographic equipment. Applying the term precisely helps teams choose controls that match the actual technical function instead of assuming a broader or unrelated meaning.

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CNSSGC

A COMSEC item used to transfer or store key in electronic form or to insert key into KYK-13, and KYK-15. cryptographic equipment. The "Common Fill Devices" are the Electronic fill devices include, but are not limited to, the DTD, SKL, SDS, and RASKI. Source: CNSSI No. 4005 (COMSEC)

Committee on National Security Systems Glossary CNSSI 4009-2015 · 2024

Cite this term

Permanent URL · stable across revisions
Election Security Glossary. (2026). Fill Device. In Election Security Glossary. Retrieved August 20, 2026, from https://electionsecurityglossary.com/glossary/fill-device

Sources

2 cited · last checked Aug 9, 2026

01

Committee on National Security Systems Glossary CNSSI 4009-2015
Committee on National Security Systems Glossary CNSSI 4009-2015

High consensus

View source

02

The Cyber Glossary
The Cyber Glossary

Multi-source

View source

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