{"action":"created","issue":{"url":"https://api.github.com/repos/typpo/textbelt/issues/53","repository_url":"https://api.github.com/repos/typpo/textbelt","labels_url":"https://api.github.com/repos/typpo/textbelt/issues/53/labels{/name}","comments_url":"https://api.github.com/repos/typpo/textbelt/issues/53/comments","events_url":"https://api.github.com/repos/typpo/textbelt/issues/53/events","html_url":"https://github.com/typpo/textbelt/issues/53","id":109184367,"number":53,"title":"Possible solution to carrier blocking","user":{"login":"vdrey","id":7849488,"avatar_url":"https://avatars.githubusercontent.com/u/7849488?v=3","gravatar_id":"","url":"https://api.github.com/users/vdrey","html_url":"https://github.com/vdrey","followers_url":"https://api.github.com/users/vdrey/followers","following_url":"https://api.github.com/users/vdrey/following{/other_user}","gists_url":"https://api.github.com/users/vdrey/gists{/gist_id}","starred_url":"https://api.github.com/users/vdrey/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/vdrey/subscriptions","organizations_url":"https://api.github.com/users/vdrey/orgs","repos_url":"https://api.github.com/users/vdrey/repos","events_url":"https://api.github.com/users/vdrey/events{/privacy}","received_events_url":"https://api.github.com/users/vdrey/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/typpo/textbelt/labels/help-wanted","name":"help-wanted","color":"009800"}],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":21,"created_at":"2015-09-30T21:35:41Z","updated_at":"2016-03-22T03:21:08Z","closed_at":null,"body":"So in #11, people were saying that they think that Tmobile is blocking textbelt.com.\r\n\r\nWe don't know if they are doing that, but if they are, it is likely because they were receiving massive amounts of emails from the textbelt.com domain, due to textbelt not being able to determine what number corresponds to what carrier, and sending messages to all carriers on the list. I *think* I might have a solution to that.\r\n\r\nBefore I describe that solution, just know: I don't know anything about JS, so I am of no use in implementing this solution, or determining whether it is feasible or not. This is just an idea I had.\r\n\r\nAs far as I understand, when an email is sent using smtp, and the user does not exist, the server responds with error code 550.\r\n\r\nMy idea is that if textbelt tracked which servers responded with 550, and which server accepted the message, you could determine the carrier for that number, and only send messages to that carrier in the future.\r\n\r\nAgain, I could be completely wrong, but this is just what came to mind. Any thoughts?"},"comment":{"url":"https://api.github.com/repos/typpo/textbelt/issues/comments/199612045","html_url":"https://github.com/typpo/textbelt/issues/53#issuecomment-199612045","issue_url":"https://api.github.com/repos/typpo/textbelt/issues/53","id":199612045,"user":{"login":"peeeeeter","id":883184,"avatar_url":"https://avatars.githubusercontent.com/u/883184?v=3","gravatar_id":"","url":"https://api.github.com/users/peeeeeter","html_url":"https://github.com/peeeeeter","followers_url":"https://api.github.com/users/peeeeeter/followers","following_url":"https://api.github.com/users/peeeeeter/following{/other_user}","gists_url":"https://api.github.com/users/peeeeeter/gists{/gist_id}","starred_url":"https://api.github.com/users/peeeeeter/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/peeeeeter/subscriptions","organizations_url":"https://api.github.com/users/peeeeeter/orgs","repos_url":"https://api.github.com/users/peeeeeter/repos","events_url":"https://api.github.com/users/peeeeeter/events{/privacy}","received_events_url":"https://api.github.com/users/peeeeeter/received_events","type":"User","site_admin":false},"created_at":"2016-03-22T03:21:08Z","updated_at":"2016-03-22T03:21:08Z","body":"A couple years ago, I had the same idea that the original post was about.  I run a hosting company, and from time to time would run a manual telnet SMTP session, one command at a time.  In the back and forth of an SMTP session, you specify the \"To\" address, then get back a response, which SHOULD include and error if the \"to\" address doesn't exist.  My initial testing showed I could get half way through the SMTP session, then abort if I get the error after specifying the to address, thus avoiding a bounce or ban.... I wrote it all up in php or perl, staying up half the night.  Once I finished and plugged in more carriers, I realized, MUCH to my disappointment, that half of the US carriers DID NOT check for a valid \"TO\" address.  So, I chalked that up as a waste of time.  I guess it's possible more of the carrier's gateways do that now.\r\n\r\nI just wanted to share my experience with the original poster's idea.."}}