SIP response code list in Skype for Business

SIP response code list 
When we are analyzing logs from Skype for business in Snooper, we can see too many codes 
and sometimes we are not sure what a code mean. 

Is for that I can give you a list of the codes with their description. 
For SIP 2.0 we have six different Status-codes (From 100 to 699) The most important is the 
first digit, not really matter the other two because they don’t have a categorization role, 
and therefore we are going to focus in the first digit and we can call “1xx response” 
for all status code between 100 and 199, the same for “2xx response” for all status code 
between 200 and 299, and so on…
This is the complete list of response codes:
 Provisional — request received, continuing to process the  request
 Success — the action was successfully received, understood and accepted;
 Redirection — further action needs to be taken in order to complete the request;
 Client Error — the request contains bad syntax or cannot be fulfilled at this server;
 Server Error — the server failed to fulfill an apparently valid request;
 Global Failure — the request cannot be fulfilled at any server.

Into the snooper there is an option to see the call flow as is shown in the follow figure:

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coordsize="21600,21600" o:spt="75" o:preferrelative="t" path="m@4@5l@4@11@9@11@9@5xe"
filled="f" stroked="f">

<v:shape id="Picture_x0020_2" o:spid="_x0000_i1026" type="#_x0000_t75"
<v:imagedata src="file:///C:\Users\GONZAN~1\AppData\Local\Temp\msohtmlclip1\01\clip_image001.png"
With a result very similar to:

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o:spid="_x0000_i1025" type="#_x0000_t75" style='width:417.6pt;height:639pt;
<v:imagedata src="file:///C:\Users\GONZAN~1\AppData\Local\Temp\msohtmlclip1\01\clip_image003.png"
Where we can see the response codes and the first table can help you to understand 
what’s going on with your call.
With this information I hope you can find root causes of your Skype for business environment.

your comment/feedback is more than welcome.