NPN (Next Protocol Negotiation)
E209794
NPN (Next Protocol Negotiation) is a now-deprecated TLS extension that allowed a client and server to agree on which application-layer protocol (such as SPDY or HTTP/2) to use over a secure connection.
All labels observed (2)
| Label | Occurrences |
|---|---|
| NPN (Next Protocol Negotiation) canonical | 1 |
| Next Protocol Negotiation | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T1881575 — 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: NPN (Next Protocol Negotiation) Context triple: [SPDY, negotiationMechanism, NPN (Next Protocol Negotiation)]
-
A.
HTTP/2
HTTP/2 is a major revision of the Hypertext Transfer Protocol that introduced features like multiplexing, header compression, and server push to significantly improve web performance over HTTP/1.1.
-
B.
NSS
The National Security Strategy of the United States (NSS) is a periodic policy document that outlines the U.S. government's overarching national security priorities, objectives, and approaches to global challenges.
-
C.
HTTP/3
HTTP/3 is the third major version of the Hypertext Transfer Protocol, built on the QUIC transport protocol to provide faster, more reliable, and secure web communication.
-
D.
RFC 5246
RFC 5246 is the Internet Engineering Task Force (IETF) standard that specifies Transport Layer Security (TLS) version 1.2, a widely used protocol for securing communications over computer networks.
-
E.
QUIC
QUIC is a modern, multiplexed transport protocol developed by Google and standardized by the IETF that runs over UDP to provide faster, more secure, and reliable web connections than traditional TCP-based HTTPS.
- 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: NPN (Next Protocol Negotiation) Target entity description: NPN (Next Protocol Negotiation) is a now-deprecated TLS extension that allowed a client and server to agree on which application-layer protocol (such as SPDY or HTTP/2) to use over a secure connection.
-
A.
HTTP/2
HTTP/2 is a major revision of the Hypertext Transfer Protocol that introduced features like multiplexing, header compression, and server push to significantly improve web performance over HTTP/1.1.
-
B.
NSS
The National Security Strategy of the United States (NSS) is a periodic policy document that outlines the U.S. government's overarching national security priorities, objectives, and approaches to global challenges.
-
C.
HTTP/3
HTTP/3 is the third major version of the Hypertext Transfer Protocol, built on the QUIC transport protocol to provide faster, more reliable, and secure web communication.
-
D.
RFC 5246
RFC 5246 is the Internet Engineering Task Force (IETF) standard that specifies Transport Layer Security (TLS) version 1.2, a widely used protocol for securing communications over computer networks.
-
E.
QUIC
QUIC is a modern, multiplexed transport protocol developed by Google and standardized by the IETF that runs over UDP to provide faster, more secure, and reliable web connections than traditional TCP-based HTTPS.
- F. None of above. chosen
Statements (35)
| Predicate | Object |
|---|---|
| instanceOf |
TLS extension
ⓘ
application-layer protocol negotiation mechanism ⓘ |
| abbreviation | NPN ⓘ |
| category |
Internet protocol
ⓘ
Web performance technology ⓘ |
| compatibility | non-NPN peers fall back to default protocol (typically HTTP/1.1) ⓘ |
| definedBy | Google ⓘ |
| deploymentStatus |
largely removed from modern TLS libraries
ⓘ
largely removed from modern browsers ⓘ |
| designGoal |
avoid protocol negotiation via ALTSVC or separate ports
ⓘ
enable multiple application protocols over a single TLS port ⓘ |
| fullName |
Next Protocol Negotiation
ⓘ
linked to:
NPN (Next Protocol Negotiation)
|
| IETFConsensus | superseded by ALPN design ⓘ |
| layer | transport layer security ⓘ |
| negotiationDirection | client-server ⓘ |
| negotiationPhase | TLS handshake ⓘ |
| obsoletedBy | widespread adoption of ALPN in HTTP/2 ⓘ |
| operatesOver | TLS ⓘ |
| protocolSelection | server selects protocol from client-offered list ⓘ |
| purpose | negotiate application-layer protocol over TLS ⓘ |
| relatedTo |
ALPN (Application-Layer Protocol Negotiation)
ⓘ
HTTP/2 ⓘ SPDY ⓘ |
| replacedBy | ALPN (Application-Layer Protocol Negotiation) ⓘ |
| requires |
TLS client support
ⓘ
TLS server support ⓘ |
| securityProperty | does not change TLS security guarantees ⓘ |
| standardizationStatus | not standardized by IETF as final RFC ⓘ |
| status | deprecated ⓘ |
| supports |
HTTP/2
ⓘ
SPDY ⓘ |
| usedFor | selecting application protocol after TLS handshake ⓘ |
| usedIn |
Google Chrome
ⓘ
SPDY deployments ⓘ |
| visibility | encrypted within TLS handshake ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: NPN (Next Protocol Negotiation) Description of subject: NPN (Next Protocol Negotiation) is a now-deprecated TLS extension that allowed a client and server to agree on which application-layer protocol (such as SPDY or HTTP/2) to use over a secure connection.
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.
linked to: NPN (Next Protocol Negotiation)