Registrations

A registration is a private user identity registered with the S-CSCF, with its registered implicit registration sets.

List Registrations

This path returns the list of registered private identities.

Method	Path
GET	/api/v1/registrations

Query Parameters

Name	In	Type	Default	Allowed	Description
search	query	str			Substring of a private or public identity.
page	query	int	1	>= 1	1-based page index.
per_page	query	int	25	1…100	Number of items per page.

Response Fields

Field	Type	Description
impi	string	Private user identity.
implicit_registration_sets	array	Registered implicit registration sets of the private identity. A set registers and deregisters as one (TS 23.228 §5.2.1a.0).
implicit_registration_sets[].hss	object	Origin-Host (host) and Origin-Realm (realm) of the last Cx answer for the set. Absent while unknown.
implicit_registration_sets[].identities	array	Public user identities of the set.
identities[].uri	string	Public user identity.
identities[].display_name	string	Display name. Absent if none.
identities[].barred	boolean	Whether the identity is barred.
identities[].registered_with	array	Other private identities a request to this public identity reaches (TS 24.229 §5.4.3.3 step 8).
implicit_registration_sets[].contacts	array	Unexpired contacts bound to the set. A contact bound to several sets is listed in each.
contacts[].contact	string	Contact URI.
contacts[].instance	string	Instance ID, an IMEI URN when available (TS 23.003 §13.8). Absent if none.
contacts[].reg_id	int	reg-id of the flow (RFC 5626). Absent if none.
contacts[].q	number	q-value (RFC 3841 §7.2.3).
contacts[].media	array	Media the device registered for: audio, video.
contacts[].registered_at	string	Registration time (RFC 3339).
contacts[].expires_at	string	Expiry time (RFC 3339).
contacts[].address	string	Address and port of the device, as seen by the P-CSCF. Absent if unknown.
contacts[].transport	string	udp or tcp. Absent if unknown.
contacts[].protected	boolean	Whether IPsec protects the signalling of the device.
contacts[].signalling_path	string	State of the IMS signalling path of the device: unmonitored, monitored or lost.

Sample Response

{
    "result": {
        "items": [
            {
                "impi": "[email protected]",
                "implicit_registration_sets": [
                    {
                        "hss": {
                            "host": "hss.epc.mnc001.mcc001.3gppnetwork.org",
                            "realm": "epc.mnc001.mcc001.3gppnetwork.org"
                        },
                        "identities": [
                            {
                                "uri": "sip:[email protected]",
                                "barred": true,
                                "registered_with": []
                            },
                            {
                                "uri": "tel:+15550000001",
                                "barred": false,
                                "registered_with": []
                            }
                        ],
                        "contacts": [
                            {
                                "contact": "sip:[email protected]:5064",
                                "instance": "urn:gsma:imei:35000000-000001-0",
                                "reg_id": 1,
                                "q": 1,
                                "media": ["audio", "video"],
                                "registered_at": "2026-10-26T18:20:04.512Z",
                                "expires_at": "2026-10-26T19:20:04.512Z",
                                "address": "10.45.0.2:5064",
                                "transport": "udp",
                                "protected": true,
                                "signalling_path": "monitored"
                            }
                        ]
                    }
                ]
            }
        ],
        "page": 1,
        "per_page": 25,
        "total_count": 1
    }
}

Re-authenticate a Registration

This path brings forward the expiry of the bindings of a registered private identity and has its next REGISTER challenged (TS 24.229 §5.4.1.6).

Method	Path
POST	/api/v1/registrations/{impi}/reauthenticate

Path Parameters

Name	Type	Description
impi	string	Private user identity.

Response Codes

Code	Description
202	Re-authentication started.
404	The private identity is not registered.
503	The IMS is restarting to apply its settings.

Sample Response

{
    "result": {
        "impi": "[email protected]"
    }
}