RFC 7518

Q: What does the Introduction section cover in RFC 7518 — JWA?

The Introduction section provides detailed technical specifications, security considerations, and implementation guidance as documented in RFC 7518 — JWA. This content is part of the BLACKLABS RFC Reference Library.

Q: What does the JWS Signature Algorithms section cover in RFC 7518 — JWA?

The JWS Signature Algorithms section provides detailed technical specifications, security considerations, and implementation guidance as documented in RFC 7518 — JWA. This content is part of the BLACKLABS RFC Reference Library.

Q: What does the JWE Key Management Algorithms section cover in RFC 7518 — JWA?

The JWE Key Management Algorithms section provides detailed technical specifications, security considerations, and implementation guidance as documented in RFC 7518 — JWA. This content is part of the BLACKLABS RFC Reference Library.

Q: What does the JWE Content Encryption Algorithms section cover in RFC 7518 — JWA?

The JWE Content Encryption Algorithms section provides detailed technical specifications, security considerations, and implementation guidance as documented in RFC 7518 — JWA. This content is part of the BLACKLABS RFC Reference Library.

Q: What does the 3GPP Algorithm Selection section cover in RFC 7518 — JWA?

The 3GPP Algorithm Selection section provides detailed technical specifications, security considerations, and implementation guidance as documented in RFC 7518 — JWA. This content is part of the BLACKLABS RFC Reference Library.

BLACKLABS

JSON Web Algorithms (JWA)

Standards Track

May 2015

Abstract: JWA registers cryptographic algorithms for use with JWS, JWE, and JWK. It defines the algorithm identifiers used in JWS 'alg' and JWE 'alg'/'enc' header parameters.

Canonical source: https://www.rfc-editor.org/rfc/rfc7518 | IETF Datatracker

1. Introduction

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JWA defines the set of cryptographic algorithms available in the JOSE ecosystem. Each algorithm has a registered identifier used in JWS/JWE headers to indicate the cryptographic operations performed.

2. JWS Signature Algorithms

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Identifier	Algorithm	Key Type	Requirement
HS256	HMAC-SHA-256	oct (symmetric)	Required
RS256	RSASSA-PKCS1-v1_5 + SHA-256	RSA	Recommended
RS384	RSASSA-PKCS1-v1_5 + SHA-384	RSA	Optional
ES256	ECDSA P-256 + SHA-256	EC	Recommended+
ES384	ECDSA P-384 + SHA-384	EC	Optional
PS256	RSASSA-PSS + SHA-256	RSA	Optional
EdDSA	Edwards-curve DSA	OKP	Optional
none	No signature	—	MUST NOT for security tokens

3. JWE Key Management Algorithms

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Identifier	Algorithm	Description
RSA-OAEP	RSAES OAEP	RSA with SHA-1 OAEP padding
RSA-OAEP-256	RSAES OAEP + SHA-256	RSA with SHA-256 OAEP (preferred)
A128KW	AES-128 Key Wrap	Symmetric key wrapping
A256KW	AES-256 Key Wrap	Symmetric key wrapping
ECDH-ES	ECDH Ephemeral Static	Direct key agreement
ECDH-ES+A128KW	ECDH-ES + A128KW	Key agreement + wrapping
ECDH-ES+A256KW	ECDH-ES + A256KW	Key agreement + wrapping

4. JWE Content Encryption Algorithms

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Identifier	Algorithm	Key Size
A128CBC-HS256	AES-128-CBC + HMAC-SHA-256	256 bits
A256CBC-HS512	AES-256-CBC + HMAC-SHA-512	512 bits
A128GCM	AES-128-GCM	128 bits
A256GCM	AES-256-GCM	256 bits

5. 3GPP Algorithm Selection

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JWT signing: ES256 (ECDSA P-256) preferred, RS256 (RSA-2048) as fallback
N32-f JWE: ECDH-ES+A256KW for key management, A256GCM for content encryption
Avoid: 'none' algorithm, RSAES-PKCS1-v1_5 (vulnerable), symmetric algorithms for tokens
Key sizes: RSA minimum 2048 bits, EC minimum P-256