[VoiceOps] Preventing calls to cell phones with guaranteed accuracy

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They're definitely not possible across the country because long distance calls only do the LNP lookup after routing the call to the destination tandem. (That's the "L" in LNP.)

Usually this is because their numbers can't support nomadic 911.

It's more than that, long distance carriers couldn't route calls to calls ported outside the LATA without some significant changes to signalling protocols. I can believe it's all easy for numbers within your network, but IXC traffic usually hands traffic to the tandem and expects it to do the LNP part. Regards, John Levine, johnl at taugh.com, Taughannock Networks, Trumansburg NY Please consider the environment before reading this e-mail.