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SIP response codes

SIP 204 No Notification

Subscription accepted; no notifications will follow. The request succeeded.

204
Name
No Notification
Class
2xx · Success
Defined in
RFC 5839

The request succeeded.

What the response looks like

SIP/2.0 204 No Notification
Via: SIP/2.0/UDP 203.0.113.10:5060;branch=z9hG4bK776asdhds
From: <sip:101@pbx.example>;tag=1928301774
To: <sip:+15551234567@pbx.example>;tag=a6c85cf
Call-ID: a84b4c76e66710@203.0.113.10
CSeq: 2 INVITE
Content-Length: 0

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