MockaSIP - SIP Error Response Simulator

Welcome to MockaSIP

MockaSIP is a SIP error response simulator built on Kamailio, designed to help developers test how their SIP clients handle various error conditions. By sending a specific error code in the SIP INVITE user, you can instantly receive the corresponding SIP error response.

Testing error handling in SIP applications has never been easier. Simply send a request ending with a 3-digit error code, and MockaSIP will respond with the appropriate SIP error message. No complex setup, no authentication—just instant error responses for testing.

Features

🎯 Error Codes Only

Responds only to codes 300-699 (redirect, client error, server error, and global failure responses)

📖 RFC Compliant

Uses proper SIP reason phrases based on RFC 3261 and related standards

⚡ Simple Interface

No authentication or complex setup required for testing

🔧 Automatic Extraction

Extracts the last 3 digits from any SIP INVITE user to determine the error code

Behavior

Valid Error Codes (300-699): Returns the requested error code with the proper reason phrase
Non-Error Codes (100-299): Returns 400 Bad Request - Invalid Status Code (since these aren't error responses)
Invalid Codes: Returns 400 Bad Request - Invalid Status Code for codes outside the 100-699 range
Short User: Returns 400 Bad Request - User Part Too Short if the INVITE user has fewer than 3 characters
No INVITE User: Returns 484 Address Incomplete

Usage Examples

Simply dial any SIP INVITE where the user ends with a 3-digit error code:

INVITE sip:404@mockasip.com

→ Receives: 404 Not Found

INVITE sip:+353123486@mockasip.com

→ Receives: 486 Busy Here

INVITE sip:anything503@mockasip.com

→ Receives: 503 Service Unavailable

Note: Only the last 3 digits of the user matter. You can use any prefix (test, user, anything, etc.) as long as the user ends with the desired error code.

Supported Error Codes

MockaSIP supports 67 different SIP error codes across all error categories:

3xx Redirection

300 Multiple Choices
301 Moved Permanently
302 Moved Temporarily
305 Use Proxy
380 Alternative Service

4xx Client Error

400 Bad Request
401 Unauthorized
402 Payment Required
403 Forbidden
404 Not Found
405 Method Not Allowed
406 Not Acceptable
407 Proxy Authentication Required
408 Request Timeout
409 Conflict
410 Gone
411 Length Required
412 Conditional Request Failed
413 Request Entity Too Large
414 Request-URI Too Long
415 Unsupported Media Type
416 Unsupported URI Scheme
417 Unknown Resource-Priority
420 Bad Extension
421 Extension Required
422 Session Interval Too Small
423 Interval Too Brief
424 Bad Location Information
425 Bad Alert Message
428 Use Identity Header
429 Provide Referrer Identity
430 Flow Failed
433 Anonymity Disallowed
436 Bad Identity-Info
437 Unsupported Certificate
438 Invalid Identity Header
439 First Hop Lacks Outbound Support
440 Max-Breadth Exceeded
469 Bad Info Package
470 Consent Needed
480 Temporarily Unavailable
481 Call/Transaction Does Not Exist
482 Loop Detected
483 Too Many Hops
484 Address Incomplete
485 Ambiguous
486 Busy Here
487 Request Terminated
488 Not Acceptable Here
489 Bad Event
491 Request Pending
493 Undecipherable
494 Security Agreement Required

5xx Server Error

500 Internal Server Error
501 Not Implemented
502 Bad Gateway
503 Service Unavailable
504 Server Time-out
505 Version Not Supported
513 Message Too Large
555 Push Notification Service Not Supported
580 Precondition Failure

6xx Global Failure

600 Busy Everywhere
603 Decline
604 Does Not Exist Anywhere
606 Not Acceptable
607 Unwanted
608 Rejected

Use Cases

🔨 SIP Client Development

Test how your client handles various error conditions without complex infrastructure

✅ Quality Assurance

Verify error handling behavior in automated tests and CI/CD pipelines

📚 Training & Learning

Learn about different SIP error codes and their meanings in a hands-on way

🐛 Debugging

Reproduce specific error scenarios for troubleshooting and debugging