Diameter¶

Diameter peers are the HSSs, SLFs, PCRFs, DRAs, SMSCs, MMEs and SMSFs Ella IMS connects to. Routes set the realm the requests of each routed application go to.

Get the Diameter Identity¶

This path returns the Diameter identity of the IMS, derived from the operator settings.

Method	Path
GET	`/api/v1/diameter`

Response Fields¶

Field	Type	Description
`host`	string	Origin-Host of the IMS.
`realm`	string	Origin-Realm of the IMS.

Sample Response¶

{
    "result": {
        "host": "ims.ims.mnc001.mcc001.3gppnetwork.org",
        "realm": "ims.mnc001.mcc001.3gppnetwork.org"
    }
}

List Diameter Peers¶

This path returns the list of Diameter peers, in the order they were created in.

Method	Path
GET	`/api/v1/diameter/peers`

Response Fields¶

Field	Type	Description
`id`	string	Peer identifier, a UUIDv7.
`host`	string	DiameterIdentity of the peer, which must match the Origin-Host of its capabilities exchange. Empty takes the Origin-Host the peer gives.
`address`	string	IPv4 or IPv6 address of the peer.
`port`	int	Port of the peer.
`transport`	string	`tcp` or `sctp`.
`applications`	array	Applications the peer serves: `cx` for an HSS or an SLF, and `sh` and `s6c` for its IP-SM-GW functions; `rx` for a PCRF or a DRA; `sgd` for an SMSC, an MME or an SMSF.
`priority`	int	Requests try the peers serving their application by priority, lowest first, and share them between peers of the same priority. SMSCs of the same service centre are tried by priority.
`service_centres`	array	Service centre addresses of an SMSC, E.164 numbers without `+`. Absent if none.
`status`	object	Connection to the peer.
`status.state`	string	`down`, `connecting`, `open`, `suspect`, `reopen` or `closing`. `down` until the IMS has tried the peer.
`status.since`	string	Time of the last state change (RFC 3339).
`status.remote_address`	string	Remote address of the connection.
`status.host`	string	Origin-Host the peer gave in its last capabilities exchange, else the configured host.
`status.realm`	string	Origin-Realm the peer gave in its last capabilities exchange.
`status.error`	string	Why the last connection to the peer failed.

Sample Response¶

{
    "result": {
        "items": [
            {
                "id": "01a1796b-90b3-74bc-b148-bdc28999206e",
                "host": "hss.epc.mnc001.mcc001.3gppnetwork.org",
                "address": "127.0.0.1",
                "port": 3869,
                "transport": "tcp",
                "applications": ["cx"],
                "priority": 10,
                "status": {
                    "state": "down",
                    "since": "2026-10-26T18:14:14.963Z",
                    "host": "hss.epc.mnc001.mcc001.3gppnetwork.org",
                    "error": "tcp: dial tcp 127.0.0.1:0->127.0.0.1:3869: connect: connection refused"
                }
            },
            {
                "id": "01a1796b-90bb-7a57-8972-269dab84d5af",
                "host": "",
                "address": "127.0.0.1",
                "port": 3870,
                "transport": "tcp",
                "applications": ["rx"],
                "priority": 10,
                "status": {
                    "state": "down",
                    "since": "2026-10-26T18:14:14.971Z",
                    "error": "tcp: dial tcp 127.0.0.1:0->127.0.0.1:3870: connect: connection refused"
                }
            }
        ]
    }
}

Get a Diameter Peer¶

This path returns the details of a specific Diameter peer.

Method	Path
GET	`/api/v1/diameter/peers/{id}`

Path Parameters¶

Name	Type	Description
`id`	string	Peer identifier.

Response Codes¶

Code	Description
`404`	No peer has this identifier.

Sample Response¶

{
    "result": {
        "id": "01a1796b-90b3-74bc-b148-bdc28999206e",
        "host": "hss.epc.mnc001.mcc001.3gppnetwork.org",
        "address": "127.0.0.1",
        "port": 3869,
        "transport": "tcp",
        "applications": ["cx"],
        "priority": 10,
        "status": {
            "state": "down",
            "since": "2026-10-26T18:14:14.963Z",
            "host": "hss.epc.mnc001.mcc001.3gppnetwork.org",
            "error": "tcp: dial tcp 127.0.0.1:0->127.0.0.1:3869: connect: connection refused"
        }
    }
}

Create a Diameter Peer¶

This path creates a Diameter peer, which the IMS then connects to.

Method	Path
POST	`/api/v1/diameter/peers`

Request Body¶

Field	Type	Required	Description
`host`	string	No	Domain name. Unique among peers.
`address`	string	Yes	Specific IPv4 or IPv6 address.
`port`	int	No	1–65535. Default `3868`.
`transport`	string	No	`tcp` or `sctp`. Default `tcp`.
`applications`	array	Yes	At least one of `cx`, `rx`, `sh`, `s6c` and `sgd`, each once.
`priority`	int	No	0–65535. Default `10`.
`service_centres`	array	No	E.164 numbers of 1 to 15 digits, without `+`, each once. Requires `sgd` in `applications` and a `host`.

Response Codes¶

Code	Description
`409`	Another peer has the same host, or the same address and transport without a host.

Sample Request¶

{
    "host": "hss.epc.mnc001.mcc001.3gppnetwork.org",
    "address": "127.0.0.1",
    "port": 3869,
    "transport": "tcp",
    "applications": ["cx"],
    "priority": 10
}

Sample Response¶

{
    "result": {
        "id": "01a1796b-90b3-74bc-b148-bdc28999206e",
        "host": "hss.epc.mnc001.mcc001.3gppnetwork.org",
        "address": "127.0.0.1",
        "port": 3869,
        "transport": "tcp",
        "applications": ["cx"],
        "priority": 10,
        "status": {
            "state": "down"
        }
    }
}

Update a Diameter Peer¶

This path replaces a Diameter peer, which the IMS then reconnects to. The request body is that of Create a Diameter Peer.

Method	Path
PUT	`/api/v1/diameter/peers/{id}`

Path Parameters¶

Name	Type	Description
`id`	string	Peer identifier.

Response Codes¶

Code	Description
`404`	No peer has this identifier.
`409`	Another peer has the same host, or the same address and transport without a host; or the policy interface is `rx` and no other peer serves `rx`.

Sample Request¶

{
    "host": "hss.epc.mnc001.mcc001.3gppnetwork.org",
    "address": "127.0.0.1",
    "port": 3869,
    "transport": "tcp",
    "applications": ["cx"],
    "priority": 5
}

Sample Response¶

{
    "result": {
        "id": "01a1796b-90b3-74bc-b148-bdc28999206e",
        "host": "hss.epc.mnc001.mcc001.3gppnetwork.org",
        "address": "127.0.0.1",
        "port": 3869,
        "transport": "tcp",
        "applications": ["cx"],
        "priority": 5,
        "status": {
            "state": "down",
            "since": "2026-10-26T18:14:14.963Z",
            "host": "hss.epc.mnc001.mcc001.3gppnetwork.org",
            "error": "tcp: dial tcp 127.0.0.1:0->127.0.0.1:3869: connect: connection refused"
        }
    }
}

Delete a Diameter Peer¶

This path deletes a Diameter peer.

Method	Path
DELETE	`/api/v1/diameter/peers/{id}`

Path Parameters¶

Name	Type	Description
`id`	string	Peer identifier.

Response Codes¶

Code	Description
`404`	No peer has this identifier.
`409`	The policy interface is `rx` and no other peer serves `rx`.

Sample Response¶

{
    "result": {
        "message": "Diameter peer deleted"
    }
}

List Diameter Routes¶

This path returns the route of each routed application: cx, rx, sh, then s6c.

Method	Path
GET	`/api/v1/diameter/routes`

Response Fields¶

Field	Type	Description
`application`	string	`cx`, `rx`, `sh` or `s6c`.
`realm`	string	Configured realm: of the HSS for `cx`, `sh` and `s6c`, of the PCRF for `rx`. Empty if not set.
`destination_realm`	string	Destination-Realm of the requests. If `realm` is empty: the `cx` realm for `sh` and `s6c`, the home domain otherwise.
`peers`	array	Peers serving the application, in the order requests try them, each with its `id`, `host`, `priority` and `status`.

Sample Response¶

{
    "result": {
        "items": [
            {
                "application": "cx",
                "realm": "epc.mnc001.mcc001.3gppnetwork.org",
                "destination_realm": "epc.mnc001.mcc001.3gppnetwork.org",
                "peers": [
                    {
                        "id": "01a1796b-90b3-74bc-b148-bdc28999206e",
                        "host": "hss.epc.mnc001.mcc001.3gppnetwork.org",
                        "priority": 5,
                        "status": {
                            "state": "down",
                            "since": "2026-10-26T18:14:21.052Z",
                            "host": "hss.epc.mnc001.mcc001.3gppnetwork.org",
                            "error": "tcp: dial tcp 127.0.0.1:0->127.0.0.1:3869: connect: connection refused"
                        }
                    }
                ]
            },
            {
                "application": "rx",
                "realm": "",
                "destination_realm": "ims.mnc001.mcc001.3gppnetwork.org",
                "peers": [
                    {
                        "id": "01a1796b-90bb-7a57-8972-269dab84d5af",
                        "host": "",
                        "priority": 10,
                        "status": {
                            "state": "down",
                            "since": "2026-10-26T18:14:14.971Z",
                            "error": "tcp: dial tcp 127.0.0.1:0->127.0.0.1:3870: connect: connection refused"
                        }
                    }
                ]
            }
        ]
    }
}

Get a Diameter Route¶

This path returns the route of an application.

Method	Path
GET	`/api/v1/diameter/routes/{application}`

Path Parameters¶

Name	Type	Description
`application`	string	`cx`, `rx`, `sh` or `s6c`.

Response Codes¶

Code	Description
`404`	The application is not routed.

Sample Response¶

{
    "result": {
        "application": "rx",
        "realm": "",
        "destination_realm": "ims.mnc001.mcc001.3gppnetwork.org",
        "peers": [
            {
                "id": "01a1796b-90bb-7a57-8972-269dab84d5af",
                "host": "",
                "priority": 10,
                "status": {
                    "state": "down",
                    "since": "2026-10-26T18:14:14.971Z",
                    "error": "tcp: dial tcp 127.0.0.1:0->127.0.0.1:3870: connect: connection refused"
                }
            }
        ]
    }
}

Update a Diameter Route¶

This path sets the realm of an application's requests. The next request goes to the new realm.

Method	Path
PUT	`/api/v1/diameter/routes/{application}`

Path Parameters¶

Name	Type	Description
`application`	string	`cx`, `rx`, `sh` or `s6c`.

Request Body¶

Field	Type	Required	Description
`realm`	string	No	Domain name. Absent or empty restores the default.

Response Codes¶

Code	Description
`404`	The application is not routed.

Sample Request¶

{
    "realm": "epc.mnc001.mcc001.3gppnetwork.org"
}

Sample Response¶

{
    "result": {
        "application": "cx",
        "realm": "epc.mnc001.mcc001.3gppnetwork.org",
        "destination_realm": "epc.mnc001.mcc001.3gppnetwork.org",
        "peers": [
            {
                "id": "01a1796b-90b3-74bc-b148-bdc28999206e",
                "host": "hss.epc.mnc001.mcc001.3gppnetwork.org",
                "priority": 10,
                "status": {
                    "state": "down",
                    "since": "2026-10-26T18:14:14.963Z",
                    "host": "hss.epc.mnc001.mcc001.3gppnetwork.org",
                    "error": "tcp: dial tcp 127.0.0.1:0->127.0.0.1:3869: connect: connection refused"
                }
            }
        ]
    }
}