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>ISPs blocking SMTP is this actually still a thing? I know on our campus network they block SMTP on the wired network, but not on the wireless (for some bonehea
by jd3 11y ago
>ISPs blocking SMTP
is this actually still a thing? I know on our campus network they block SMTP on the wired network, but not on the wireless (for some boneheaded reason or another).
- duskwuff 11y agoAll sane residential ISPs block port 25 (SMTP) to prevent spam. All sane mail providers offer SUBMISSION (same protocol as SMTP) on port 587, which is intentionally not blocked by ISPs.
- terinjokes 11y agoI've been on ISPs that block SMTP ans SUBMISSION along with their main alternative ports because they had too much spam sent from their IPs in the past getting them added to spamhaus. Of course, they only needed to block port 25, but alas they blocked them all.
- izacus 11y agoResidental ISPs where? I've yet to see one here in EU O.o
- ciupicri 11y agoRCS & RDS in Romania [1]. Telekom in Germany [2]. [1]: http://www.rcs-rds.ro/asistenta/protejeaza-ti-calculatorul?t=smtp http://www.rcs-rds.ro/asistenta/protejeaza-ti-calculatorul?t... (in Romanian) [2]: https://www.telekom.de/hilfe/festnetz-internet-tv/sicherheit/missbrauch-von-diensten/keine-moeglichkeit-eine-e-mail-zu-senden-wegen-portsperre?samChecked=true https://www.telekom.de/hilfe/festnetz-internet-tv/sicherheit... (in German)
- duskwuff 11y agoMost residential ISPs in the US, at least. Certainly all of the big ones do (Comcast, Time Warner, AT&T, Verizon, etc); the FTC has actually specifically recommended that all US ISPs block outbound port 25 as a spam mitigation measure.