SIP 100 Trying Response Code for SIP Troubleshooting

SIP 100 Trying response code is part of the 1XX SIP Response Codes and one of the most commonly used SIP response codes in the SIP stack.

SIP works on a request-response model and 1xx SIP response codes are there to provide information on the status of network-related processes, SIP 100 Trying is one of them.

Continue reading SIP 100 Trying Response Code for SIP Troubleshooting

SIP 404 Not Found – Understanding SIP 404 Response Code

SIP 404 Not Found response belongs to the 4xx SIP code group.
A group of SIP codes that indicate a request failure and constitutes a number of codes used by SIP for communicating errors and failures.

In this blog post we will explore the SIP 404 Not Found response code and touch the different available SIP Response Codes.

But, first what is SIP?

Continue reading SIP 404 Not Found – Understanding SIP 404 Response Code

SIP Response Codes Explained

Why don’t we start with some trivia?
Did you know that SIP response codes are based on HTTP/1.1 response 404-not-foundcodes?

Actually, SIP response codes are the extent of the original HTTP ones and even define a new class with more response codes. I’ll let you know which one when we get to it.

That said, not all of the HTTP codes are relevant and mapped to SIP response codes, so if you know some HTTP, don’t expect to find them all in this list.
Continue reading SIP Response Codes Explained

Cisco SIP Gateway configuration: The Ultimate Guide

Connecting the Cisco IOS Voice Gateway to CUCM via SIP has been the preferred way to do it in the past couple of years.

The slowly dying H323 protocol (ISDN based) is not being developed anymore while SIP (HTTP based) became the industry standard for VoIP. So whenever PSTN connection is implemented via an IOS Voice Gateway, the choice should be really between SIP & MGCP.

This is how it’s done, step by step, using SIP.

Continue reading Cisco SIP Gateway configuration: The Ultimate Guide