603
SIP
603 Decline
The callee's machine was contacted successfully but the user explicitly does not wish to or cannot participate. Unlike 600, this may be because the callee doesn't want to communicate, not necessarily because they're busy.
このコードが表示される場合
When the callee explicitly declines the call. This is an active rejection, not a busy or unavailable state.
解決方法
The callee has declined. Respect their decision. Consider alternative communication methods (email, messaging).
関連コード
比較対象
ガイド
401 Unauthorized vs 403 Forbidden: When to Use Each
Security & Authentication
SIP Response Codes: Understanding VoIP Call Flow
Real-Time Protocols
SIP Call Flow: Understanding Session Setup
Real-Time Protocols
WebRTC Signaling with SIP and WebSocket
Real-Time Protocols
RFC 3261: SIP Protocol Deep Dive
Protocol Deep Dives
TLS 1.3: Faster, Simpler, More Secure
Protocol Deep Dives
用語集
Status Code
Request Method (HTTP Verb)
TLS Handshake
Authentication
TCP/IP
Port Number
NAT (Network Address Translation)
Socket
Request-Response Model
RFC (Request for Comments)
Connection-Oriented
Full-Duplex
SRV Record
SIP Dialog
Signaling
SIP Registrar
STUN (Session Traversal Utilities for NAT)
TURN (Traversal Using Relays around NAT)
SDP (Session Description Protocol)
SIP INVITE
SIP Proxy Server
SIP Redirect Server
SIP Transaction
SIP User Agent
SIP Trunk
RTP (Real-time Transport Protocol)
SRTP (Secure Real-time Transport Protocol)
SIP ACK
SIP BYE
SIP CANCEL
SIP OPTIONS
SIP SUBSCRIBE/NOTIFY
B2BUA (Back-to-Back User Agent)
SBC (Session Border Controller)
Codec Negotiation
SIP Response Classes
VoIP (Voice over IP)
Presence (SIP)
PBX (Private Branch Exchange)
MFA (Multi-Factor Authentication)
TLS Versions