| Protocol | ims | Network | 5G and LTE |
|---|---|---|---|
| Spec | RFC 3261 / 3GPP TS 24.229 | Spec Section | SIP 500 Server Internal Error failure response |
| Direction | IMS network -> UE | Message Type | SIP server-failure response |
| Full message name | IMS SIP 500 Server Internal Error |
|---|---|
| Protocol | IMS |
| Technology | 5G and LTE |
| Common deployment | VoNR and VoLTE |
| Direction | IMS network -> UE |
| Interface | Gm with onward IMS routing |
| Signaling bearer / channel | IMS SIP signaling / Server-failure response |
| Typical trigger | An internal server problem prevented normal request handling. |
| Main purpose | Signals that the failure is on the server side rather than in the basic request format. |
| Main specification | RFC 3261 / 3GPP TS 24.229, SIP 500 Server Internal Error failure response |
| Release added | See specification history |
| Procedures where used | IMS Server Failure |
500 Server Internal Error means the server hit an internal problem while handling the request.
Signals that the failure is on the server side rather than in the basic request format.
500 means the server itself had an internal problem while handling the request.
Previous message(s): IMS SIP INVITE, IMS SIP REGISTER
Next message(s): Retry if policy allows
Security context: Uses the same protected IMS signaling path as the original request.
SIP/2.0 500 Server Internal Error
Via:
From:
To:
Call-ID:
CSeq:
Retry-After: OPTIONAL
Content-Length: 0
This is SIP response syntax rather than ASN.1.
SIP/2.0 500 Server Internal Error
Via: SIP/2.0/UDP ue.example.net;branch=z9hG4bK-reg1
From: <sip:alice@example.net>;tag=reg1
To: <sip:alice@example.net>;tag=scscf1
Call-ID: reg-001@example.net
CSeq: 2 REGISTER
Content-Length: 0
| IE | Required | Description |
|---|---|---|
Status-Line | Yes | Shows the 500 failure code. |
Retry-After | Optional | Can suggest whether the sender should retry later. |
Status-LineShows the 500 failure code.
Presence: Required
In practice: In practice, compare this field with the original request and with any later release-dependent optional fields so you can see whether the network accepted the same service model the UE asked for.
Retry-AfterCan suggest whether the sender should retry later.
Presence: Optional
In practice: In practice, compare this field with the original request and with any later release-dependent optional fields so you can see whether the network accepted the same service model the UE asked for.
Likely cause: An internal service or application fault prevented processing.
What to inspect: Check whether the same request succeeds through another branch or later retry.
Next step: Treat it as an internal server issue unless the trace shows a more specific cause.
It means the server hit an internal problem while processing the SIP request.
Decode this message with the 3GPP Decoder, inspect the related message database, or open the matching call flow to see where this signaling step fits in the full procedure.