Unstable USA toll free call routing

[boatman]

On the Smart Call List (Dial Plans) page there is a 'Dial Plan Test' function. I have been testing it with a US toll free number and am getting three different results which I have pasted below. The 3 differnet results seem to come up at random and without any changes to the dial plan between trials. The only match in my dial plan is _1NxxNxxxxxx and that is for webcalldirect, however I would prefer that US toll free numbers always route to a free service. Why is this routing unstable? How can I make sure that toll free numbers are intercepted by Voxalot and sent to one their free call termination services?
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A call to:18665734678 will get forwarded to sip:16416418665734678@sip.tollfreegateway.com

A call to:18665734678 will get forwarded to sip:18665734678@tf.voipmich.com

A call to:18665734678 will get forwarded to sip:0018665734678@sip.webcalldirect.com
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[martin]

The variations are due to ENUM lookups. If you dont want ENUM then go into the dial plan entry and turn it off.
.

[wmp]

I recognize the first two as an ENUM lookup. I would guess the third trial call failed the ENUM lookup for some reason. To always route toll free calls here is what I put in my Smart Calls plan:

#  	Pattern  Replacement  	Provider
800  	_1800.  *${EXTEN}  	SIP Broker
866 	_1866. 	*${EXTEN} 	SIP Broker
877 	_1877. 	*${EXTEN} 	SIP Broker
888 	_1888. 	*${EXTEN} 	SIP Broker

The priority for these must be placed before your _1NxxNxxxxxx dial plan.

[boatman]

So this number (18665734678) has an ENUM match? Does that mean they have a SIP phone of some kind and a call to that number could be VoIP end to end without touching the POTS phone system?

I have now created dial plans to match toll free numbers. Is it a good idea to enable ENUM on these toll free number dial plans? I would think so, if the path can be VoIP end to end then the call quality should be better.

Is there a web site where I can enter a number to check if it is ENUM listed and find it's SIP address?

[martin]

Originally Posted by boatman

Is there a web site where I can enter a number to check if it is ENUM listed and find it's SIP address?

You can use ours SIPBroker - ENUM Lookup
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[boatman]

Looks like one can do an ENUM lookup with dig:
[boatman@localhost ~]$ dig +short 9.8.0.5.7.8.6.6.1.5.1.e164.org any
100 10 "u" "E2U+SIP" "!^\\+15166875089$!sip:15166875089@tx2.supernettel .com!" .
[boatman@localhost ~]$

This is interesting, I got two matches on 18665734678. I wonder if they are real SIP addresses or if this is just a way of routing toll free numbers?
[boatman@localhost ~]$ dig +short 8.7.6.4.3.7.5.6.6.8.1.e164.org any
200 10 "u" "E2U+SIP" "!^\\+1866(.*)$!sip:1866\\1@tf.voipmich.com!" .
200 10 "u" "E2U+SIP" "!^\\+1866(.*)$!sip:1641641866\\1@sip.tollfreegate way.com!" .
[boatman@localhost ~]

nslookup works too:
nslookup -sil -type=naptr 8.7.6.4.3.7.5.6.6.8.1.e164.org
Non-authoritative answer:
8.7.6.4.3.7.5.6.6.8.1.e164.org naptr = 200 10 "u" "E2U+SIP" "!^\\+1866(.*)$!sip:1866\\1@tf.voipmich.com!" .
8.7.6.4.3.7.5.6.6.8.1.e164.org naptr = 200 10 "u" "E2U+SIP" "!^\\+1866(.*)$!sip:1641641866\\1@sip.tollfreegate way.com!" .

I am surprised there doesn't seem to be an ENUM match for 61282062533, the Voxalot phone number!

[Ron]

Originally Posted by martin

The variations are due to ENUM lookups. If you dont want ENUM then go into the dial plan entry and turn it off.
.

It appears at least one of these providers has severe audio issues (it sounds like Darth Vader from Star Wars). I frequently have to dial a toll-free number several times to avoid it.