Hangup reason and SIP reasons

[macaruchi]

I am having getting differents sip hangup cause when i dial.
When I dial the call from cel I get an IVR but from my carrier I get sipcause 503 so congestion. My carrier is sending the incorrect codes or no processing the calls that are answerd by machine,IVR.

Just is a question or how carries handle the sip codes

Thks

[MJCoate]

You could ask 5 different carriers and get 5 different answers. How carriers handle SIP codes are entirely up to them. Though there are standards on how SIP should be implemented, if you are finding your carrier is not sending you the proper codes for calls, you need to contact them and let them know they are not honoring the SIP RFCs (be sure to specify exactly what isn't being honored when you contact them). It might not be them, it might be a downstream carrier.