500 and 404 errors in SIP

[glenewhittenberg]

Hello again. I am getting a fair share of 500 and 404 errors when calling overseas. My vicidial_carrier_log shows 38-CONGESTION and 1-CHANUNAVAIL on about 20% of my calls tonight. Here is a link from a tcpdump on a 404 call.

wont let me post a url. Bummer. i can send if you need to see it. it shows the flow of

1. i send invite
2. carrier sends my call is important
3. carrier sends 404 not found
4. i send ACK

I can run a dump and get a 500 error if needed also.

Any insight would be appreciated. I am pretty sure it is a carrier issue but i don't want to start throwing hand grenades until i get some feedback.

Thanks guys!

[williamconley]

1) use another carrier (if you only have ONE carrier and paychecks are riding on this ... you are doing everyone a disfavor). Professionals have Two providers. Best practices requires Three (two capable of full load and a 3rd for emergencies and quality test comparisons).

2) If your server isn't overloaded, and your internet connection is solid (ie: calls to anywhere else work just fine), then it's likely your provider. Nothin' you can do to fix it if that's the case except get a new one.

[glenewhittenberg]

I completely agree with you. We mostly do US calls during the day and we have three carriers for this. Our calls International are for a few countries and we have struck a deal with the carrier that makes this affordable. The service, connect rate and sound quality, are better than the 4 others we tested with. We are unable to use the best of the best based on cost. Thanks for the confirmation on the carrier side though.

[telecomdude1776]

Some reasons that your other carriers wouldn't accept the calls and issue a 404 error code are:
A SIP 404 is a generic error for failed to establish call (It can mean anything from "This number doesn't exist", to "You're not allowed to call this number (but it does exist)" to "System error making call")

As other numbers work, and this is a SIP trunk, you might want to check with your provider that they accept 999 calls.
You may find that you're stripping the leading 9 and asking the SIP provider to dial "99" which will fail...

[glenewhittenberg]

I spoke with my provider yesterday night on this. We are sending the proper digits to them. It appears that the numbers we called a few days back are just bad numbers. The lead brokers are crooks I will try and do some more testing next week and get a better idea.

I am also starting to use tcpdump and wireshark. It lets me follow the flow of the VoIP calls between my end and theirs. I can see drop packets per call, amount of jitter per call, view the entire conversation between both ends from call setup to tear-down, all error codes, etc. i can even play the conservation between both parties for calls that I captured. Pretty slick i think.

Thanks guys.