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VoIP Disconnect Codes - Sip 404 - Sip 403 - The Reasons and Solutions


Welcome to the master class of VoIP business and today’s lecture is about Sip disconnect codes: Sip 404 Not Found and Sip 403 Forbidden. To lower the PDD of the blog, we start the lesson immediately.


The meaning of the Sip 404 Not Found

The meaning of this code is: the request could not find a response on the other side.


Causes of this Sip Disconnect Code

Sip-404 Not Found code causes a low average success rate.


How can we define Sip-404

Find the low ASD values and analyze CDR value so you can define Sip 404 easily and take action.


The reasons for this disconnect code

  • Some providers return with this Sip message if they received the wrong numbers.

  • Maybe you are sending the traffic with wrong tec prefix

  • There is a possibility of config error on the other side

  • Maybe the route was down


What should we do if we receive Sip 404

  1. We should control the numbers and test them with another direct vendor.

  2. Confirm the tech prefix that we send to the vendor

  3. If the numbers and tech prefixes are correct but we still get this error code then we need to inform the vendor about this situation.


The meaning of SIP-403 Forbidden

The answer that is received when a forbidden request sent to the other side.


The consequences of Sip 403

This code causes to lower the VoIP traffic’s ASR rates. Low ASR rates are not desired values for healthy traffic.


The reasons fo Sip 403 Forbidden

  • Maybe there is a problem with IP

  • Problem with numbers

  • The A number is blocked or it’s an unwanted number

  • Route was down


How can we define this Sip

Analyze the CDR value of the traffic who have low average success rate rates. And also you can look for the numbers that receive Forbid.


The things that you can do

  1. Check the numbers, test on the different vendors and if they work, control the IP.

  2. If everything is okay about numbers that we called or IP then we need to check the numbers of that call.

  3. If there is no problem with traffic and the call is okay to be forwarded to the vendor smoothly, you should inform the vendor.

For other VoIP disconnect Codes and general questions

You can reach us from our web site or social media accounts and ask anything you wonder about VoIP business. We will be very happy to help you with all the questions.

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