{
  "id": "communication/rtp-ssrc-collision",
  "signature": "RTP SSRC collision detected: duplicate SSRC 0x%08X",
  "signature_zh": "RTP SSRC冲突检测到：重复的SSRC 0x%08X",
  "regex": "RTP SSRC collision detected: duplicate SSRC 0x[0-9A-Fa-f]{8}",
  "domain": "communication",
  "category": "protocol_error",
  "subcategory": null,
  "root_cause": "Two RTP endpoints in the same session are using the same synchronization source identifier, causing packet misrouting.",
  "root_cause_type": "generic",
  "root_cause_zh": "同一RTP会话中的两个端点使用了相同的同步源标识符，导致数据包错误路由。",
  "versions": [
    {
      "version": "libWebRTC M120",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    },
    {
      "version": "PJSIP 2.13.1",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    },
    {
      "version": "FFmpeg 6.1",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    }
  ],
  "os_specific": {},
  "dead_ends": [
    {
      "action": "Restart all RTP streams simultaneously",
      "why_fails": "Collision may reoccur if SSRCs are generated from the same seed or algorithm without randomization.",
      "fail_rate": 0.6,
      "condition": "",
      "sources": []
    },
    {
      "action": "Increase SSRC pool size or use fixed SSRCs",
      "why_fails": "Fixed SSRCs can cause permanent collisions in multi-party calls; randomization is required by RFC 3550.",
      "fail_rate": 0.8,
      "condition": "",
      "sources": []
    }
  ],
  "workarounds": [
    {
      "action": "Implement RTCP BYE and re-invite with new random SSRC. Example in Python: import random; new_ssrc = random.randint(0, 0xFFFFFFFF); send_rtcp_bye(old_ssrc); start_rtp(new_ssrc)",
      "success_rate": 0.85,
      "how": "Implement RTCP BYE and re-invite with new random SSRC. Example in Python: import random; new_ssrc = random.randint(0, 0xFFFFFFFF); send_rtcp_bye(old_ssrc); start_rtp(new_ssrc)",
      "condition": "",
      "sources": []
    },
    {
      "action": "Enable SSRC collision detection and handling in your RTP stack (e.g., in PJSIP set pjsua_media_config.rtp_collision_detection=1)",
      "success_rate": 0.9,
      "how": "Enable SSRC collision detection and handling in your RTP stack (e.g., in PJSIP set pjsua_media_config.rtp_collision_detection=1)",
      "condition": "",
      "sources": []
    }
  ],
  "workarounds_zh": [
    "Implement RTCP BYE and re-invite with new random SSRC. Example in Python: import random; new_ssrc = random.randint(0, 0xFFFFFFFF); send_rtcp_bye(old_ssrc); start_rtp(new_ssrc)",
    "Enable SSRC collision detection and handling in your RTP stack (e.g., in PJSIP set pjsua_media_config.rtp_collision_detection=1)"
  ],
  "transition_graph": {
    "leads_to": [],
    "preceded_by": [],
    "frequently_confused_with": []
  },
  "official_doc_url": "https://datatracker.ietf.org/doc/html/rfc3550#section-8.2",
  "official_doc_section": null,
  "error_code": null,
  "verification_tier": "ai_generated",
  "confidence": 0.85,
  "fix_success_rate": 0.8,
  "resolvable": "partial",
  "first_seen": "2024-03-15",
  "last_confirmed": "2024-06-01",
  "last_updated": "2024-06-01",
  "evidence_count": 1,
  "tags": [],
  "locale": "en",
  "aliases": []
}