Max Fragment Length extension

E258092

TLS extension Transport Layer Security feature

The Max Fragment Length extension is a Transport Layer Security (TLS) protocol feature that allows clients and servers to negotiate smaller-than-default record sizes to accommodate constrained environments or avoid IP fragmentation.

Try in SPARQL Jump to: Surface forms Disambiguation Statements Elicitation Referenced by

All labels observed (3)

Label	Occurrences
Max Fragment Length extension canonical	2
Max Fragment Length	1
Max Fragment Length Negotiation extension	1

How this entity was disambiguated

This entity first appeared as the object of triple T2359741 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.

NED1 Entity disambiguation (via context triple) gpt-5-mini-2025-08-07

Target entity: Max Fragment Length extension
Context triple: [RFC 3546, defines, Max Fragment Length extension]

A. IEEE 802.1Qfz
IEEE 802.1Qfz is an Ethernet networking standard that defines enhancements for time-sensitive networking, focusing on improved traffic management and deterministic communication.
B. RFC 6146
RFC 6146 is an IETF standard that specifies the behavior and requirements for NAT64, enabling IPv6-only clients to communicate with IPv4 servers through protocol translation.
C. IEEE 802.1Qfj
IEEE 802.1Qfj is an amendment to the IEEE 802.1Q standard that defines enhancements for deterministic, time-sensitive networking in bridged and virtualized Ethernet networks.
D. RFC 6145
RFC 6145 is an IETF standard that specifies the stateless translation mechanism between IPv4 and IPv6 packet headers used in NAT64 environments.
E. IEEE 802.1Qfk
IEEE 802.1Qfk is an IEEE networking standard that defines mechanisms for enhanced VLAN and Ethernet bridging behavior within the broader IEEE 802.1 family.
F. None of above. chosen
G. Unsure - the case is ambiguous/there is not enough information to decide.

NED2 Entity disambiguation (via description) gpt-5-mini-2025-08-07

Target entity: Max Fragment Length extension
Target entity description: The Max Fragment Length extension is a Transport Layer Security (TLS) protocol feature that allows clients and servers to negotiate smaller-than-default record sizes to accommodate constrained environments or avoid IP fragmentation.

A. IEEE 802.1Qfz
IEEE 802.1Qfz is an Ethernet networking standard that defines enhancements for time-sensitive networking, focusing on improved traffic management and deterministic communication.
B. RFC 6146
RFC 6146 is an IETF standard that specifies the behavior and requirements for NAT64, enabling IPv6-only clients to communicate with IPv4 servers through protocol translation.
C. IEEE 802.1Qfj
IEEE 802.1Qfj is an amendment to the IEEE 802.1Q standard that defines enhancements for deterministic, time-sensitive networking in bridged and virtualized Ethernet networks.
D. RFC 6145
RFC 6145 is an IETF standard that specifies the stateless translation mechanism between IPv4 and IPv6 packet headers used in NAT64 environments.
E. IEEE 802.1Qfk
IEEE 802.1Qfk is an IEEE networking standard that defines mechanisms for enhanced VLAN and Ethernet bridging behavior within the broader IEEE 802.1 family.
F. None of above. chosen

Statements (48)

Predicate	Object
instanceOf	TLS extension ⓘ Transport Layer Security feature ⓘ
abbreviation	MFL ⓘ
allowsMaxFragmentLength	1024 bytes ⓘ 2048 bytes ⓘ 4096 bytes ⓘ 512 bytes ⓘ
appliesTo	TLS application data records ⓘ TLS handshake records ⓘ
benefit	helps constrained embedded devices ⓘ helps devices with small MTUs ⓘ reduces memory requirements for record buffers ⓘ reduces risk of IP-layer fragmentation ⓘ
category	TLS performance and transport optimization ⓘ
defaultRecordSizeWithoutExtension	16384 bytes ⓘ 2^14 bytes ⓘ
definedBy	Internet Engineering Task Force ⓘ
definedIn	RFC 6066 ⓘ
doesNotAffect	TLS alert record size semantics ⓘ
extensionTypeCode	1 ⓘ
IANAExtensionType	max_fragment_length ⓘ
introducedYear	2011 ⓘ
negotiates	maximum TLS record payload size ⓘ
negotiationDirection	client to server ⓘ
negotiationOutcome	applies for the duration of the TLS session ⓘ
notApplicableTo	TLS 1.3 ⓘ linked to: RFC 8446
partOfProtocol	TLS 1.0 ⓘ TLS 1.1 ⓘ TLS 1.2 ⓘ Transport Layer Security ⓘ linked to: TLS
purpose	to accommodate constrained environments ⓘ to avoid IP fragmentation ⓘ to negotiate smaller-than-default TLS record sizes ⓘ
relatedTo	IP fragmentation ⓘ TLS record layer ⓘ linked to: TLS path MTU ⓘ
requires	support by both TLS client and TLS server ⓘ
RFCNumber	6066 ⓘ
scope	per TLS session ⓘ
sectionOfRFC	RFC 6066 Section 4 ⓘ linked to: RFC 6066
securityConsideration	may increase observability of traffic patterns due to more records ⓘ smaller records increase per-record overhead ⓘ
selectionRule	server must not select a larger fragment length than offered by client ⓘ server must not select a value not offered by client ⓘ
standardTrack	IETF Standards Track ⓘ linked to: IETF Internet standards process
status	standardized ⓘ
usedIn	TLS ClientHello ⓘ TLS ServerHello ⓘ linked to: ServerHello with extensions

How these facts were elicited

Referenced by (4)

Full triples — surface form annotated when it differs from this entity's canonical label.

RFC 3546 → defines → Max Fragment Length extension ⓘ

RFC 6066 → defines → Max Fragment Length extension ⓘ

Transport Layer Security (TLS) Extensions: Extension Definitions → defines → Max Fragment Length Negotiation extension ⓘ

linked to: Max Fragment Length extension

RFC 4366 → definesExtension → Max Fragment Length ⓘ