I‑CSCF
E127333
I‑CSCF (Interrogating Call Session Control Function) is a key SIP server in the IP Multimedia Subsystem that handles incoming session setup requests and routes them to the appropriate network entities.
All labels observed (3)
| Label | Occurrences |
|---|---|
| I-CSCF | 3 |
| Interrogating-CSCF | 3 |
| I‑CSCF canonical | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T1077431 — 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: I‑CSCF Context triple: [IMS, includesComponent, I‑CSCF]
-
A.
P‑CSCF
P‑CSCF (Proxy Call Session Control Function) is the first contact point for user equipment in an IP Multimedia Subsystem (IMS) network, handling signaling, security, and routing of SIP messages.
-
B.
MGCF
MGCF (Media Gateway Control Function) is a core network element in IP Multimedia Subsystem (IMS) architectures that controls media gateways and manages signaling between IP-based and traditional circuit-switched telephony networks.
-
C.
PCRF
PCRF (Policy and Charging Rules Function) is a core network element in modern mobile systems that dynamically manages policy control and charging rules for data services.
-
D.
CSFB (Circuit Switched Fallback)
CSFB (Circuit Switched Fallback) is a mobile network feature that allows LTE devices to temporarily switch to a legacy 2G/3G circuit-switched network to handle voice calls and SMS.
-
E.
H.248
H.248 is an ITU-T protocol, also known as Megaco, used for controlling media gateways in next-generation and IP multimedia networks.
- 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: I‑CSCF Target entity description: I‑CSCF (Interrogating Call Session Control Function) is a key SIP server in the IP Multimedia Subsystem that handles incoming session setup requests and routes them to the appropriate network entities.
-
A.
P‑CSCF
P‑CSCF (Proxy Call Session Control Function) is the first contact point for user equipment in an IP Multimedia Subsystem (IMS) network, handling signaling, security, and routing of SIP messages.
-
B.
MGCF
MGCF (Media Gateway Control Function) is a core network element in IP Multimedia Subsystem (IMS) architectures that controls media gateways and manages signaling between IP-based and traditional circuit-switched telephony networks.
-
C.
PCRF
PCRF (Policy and Charging Rules Function) is a core network element in modern mobile systems that dynamically manages policy control and charging rules for data services.
-
D.
CSFB (Circuit Switched Fallback)
CSFB (Circuit Switched Fallback) is a mobile network feature that allows LTE devices to temporarily switch to a legacy 2G/3G circuit-switched network to handle voice calls and SMS.
-
E.
H.248
H.248 is an ITU-T protocol, also known as Megaco, used for controlling media gateways in next-generation and IP multimedia networks.
- F. None of above. chosen
Statements (48)
| Predicate | Object |
|---|---|
| instanceOf |
Call Session Control Function
ⓘ
IMS network element ⓘ SIP server ⓘ |
| abbreviation |
I-CSCF
ⓘ
linked to:
I‑CSCF
|
| belongsToDomain |
VoIP
ⓘ
mobile networks ⓘ telecommunications ⓘ |
| category |
control plane function
ⓘ
core network function ⓘ |
| definedInStandard |
3GPP IMS specifications
ⓘ
3GPP TS 23.228 ⓘ 3GPP TS 24.229 ⓘ |
| fullName | Interrogating Call Session Control Function ⓘ |
| function |
hide internal network topology from external networks
ⓘ
perform initial routing of incoming SIP requests ⓘ select appropriate S-CSCF for a user ⓘ support interconnection with other operators ⓘ support roaming subscribers ⓘ |
| interfacesWith |
BGCF
ⓘ
HSS ⓘ MGCF ⓘ P-CSCF ⓘ
linked to:
P‑CSCF
S-CSCF ⓘ
linked to:
S‑CSCF
|
| networkRole | interrogating CSCF ⓘ |
| operatesAt | IMS network edge ⓘ |
| partOf | IP Multimedia Subsystem ⓘ |
| primaryRole |
handle incoming SIP session setup requests from other networks
ⓘ
route SIP requests to appropriate IMS entities ⓘ |
| queries | Home Subscriber Server ⓘ |
| relatedTo |
BGCF
ⓘ
E-CSCF ⓘ HSS ⓘ P-CSCF ⓘ
linked to:
P‑CSCF
S-CSCF ⓘ
linked to:
S‑CSCF
|
| routingDecisionBasedOn |
operator routing policies
ⓘ
user identity information from HSS ⓘ |
| securityRole |
screening of incoming SIP requests
ⓘ
topology hiding ⓘ |
| supportsService |
multimedia telephony
ⓘ
rich communication services ⓘ voice over IMS ⓘ |
| technologyGeneration |
3G
ⓘ
4G LTE ⓘ 5G core IMS ⓘ |
| usesInterface |
Cx interface
ⓘ
Dx interface ⓘ Mw interface ⓘ |
| usesProtocol | Session Initiation Protocol ⓘ |
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: I‑CSCF Description of subject: I‑CSCF (Interrogating Call Session Control Function) is a key SIP server in the IP Multimedia Subsystem that handles incoming session setup requests and routes them to the appropriate network entities.
Referenced by (7)
Full triples — surface form annotated when it differs from this entity's canonical label.
linked to: I‑CSCF
linked to: I‑CSCF