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 # email
 Information about how to configure email servers, services, etc.
 
-## Links
-- https://support.google.com/a/answer/81126 Email sender guidelines
+## Tester
 - https://mecsa.jrc.ec.europa.eu/en/ EU Email Communications Security Assessment (MECSA)
 - https://mxtoolbox.com/supertool
+- https://mxtoolbox.com/dmarc/dmarc-email-tools SPF DKIM DMARC
+- https://dmarcly.com/tools/ SPF DKIM DMARC
 - https://www.mail-tester.com/
 - https://www.emailchecky.com/en/
-- https://dnssec-debugger.verisignlabs.com/
-- https://www.experte.de/dns-check/dnssec
 - https://ssl-tools.net/
 - https://www.checktls.com/index.html
-- https://www.nospamproxy.de/wp-content/uploads/Praxisleitfaden-DKIM-SPF-DMARC-DANE-1.pdf
 - https://www.debouncer.com/reverse-dns-check
+- https://testconnectivity.microsoft.com/tests/exo
+- https://testconnectivity.microsoft.com/tests/O365DaneValidation/input
+
+## Wissen
+- https://support.google.com/a/answer/81126 Email sender guidelines
+- https://www.nospamproxy.de/wp-content/uploads/Praxisleitfaden-DKIM-SPF-DMARC-DANE-1.pdf
 - https://www.internetsociety.org/deploy360/dnssec/statistics/
 - https://stats.labs.apnic.net/dnssec/
 - https://stats.labs.apnic.net/dnssec
 - https://www.windowspro.de/news/microsoft-unterstuetzt-dane-dnssec-exchange-online/04980.html
-- https://testconnectivity.microsoft.com/tests/exo
-- https://testconnectivity.microsoft.com/tests/O365DaneValidation/input
-- https://mxtoolbox.com/dmarc/dmarc-email-tools SPF DKIM DMARC
-- https://dmarcly.com/tools/ SPF DKIM DMARC
+- https://blog.lindenberg.one/EmailSicherheitsTest
+- https://www.heise.de/news/Transportsicherheit-BSI-zertifiziert-E-Mail-Dienste-nach-neuer-Richtlinie-9349117.html
+- https://certified-senders.org/wp-content/uploads/2020/02/E-Mail-Transportverschluesselung-STARTTLS-vs.-DANE-vs.-MTA-STS_updated.pdf
+- https://www.golem.de/news/smtp-mta-sts-bringt-sichere-verschluesselung-zwischen-mailservern-1809-136853.html
+- https://beta-its.de/ultimative-domain-sicherheit-dnssec-mta-sts-dane-dmarc
+- https://www.hornetsecurity.com/de/services/email-authentifizierung/
+- https://www.anubisnetworks.com/blog/dmarc_dane_explained
+
+## DNSSEC
+### Allgemein
+- https://dnssec-debugger.verisignlabs.com/
+- https://www.experte.de/dns-check/dnssec
+
+## Hoster
+### Allgemein
+- https://www.hosttest.de/artikel/groesste-webhostinganbieter-in-deutschland
+- https://www.trending.de/hosting/die-10-groessten-deutschen-hoster-und-meine-empfehlung/
+
+### Hoster: IONOS
+- https://www.ionos.de/hilfe/domains/domain-guard/dnssec-einrichten-und-verwalten/
+
+### Hoster: Strato
+- https://www.strato.de/faq/domains/wie-kann-ich-bei-strato-meine-dns-eintraege-verwalten/
+- https://www.strato.de/faq/domains/sichern-sie-ihre-webseite-mit-dnssec/
+- https://www.strato.de/faq/domains/was-ist-domain-guard/
+
+### Hoster: Hetzner
+- https://docs.hetzner.com/de/dns-console/dns/general/dnssec/
+- https://docs.hetzner.com/dns-console/dns/general/dnssec/