Resources added for SPF (#1603)

content/roadmaps/102-devops/content/103-networking-protocols/103-emails/105-spf.md

@@ -1 +1,7 @@
-# Spf
+# SPF
+
+Sender Policy Framework (SPF) is used to authenticate the sender of an email. With an SPF record in place, Internet Service Providers can verify that a mail server is authorized to send email for a specific domain. An SPF record is a DNS TXT record containing a list of the IP addresses that are allowed to send email on behalf of your domain.
+
+<ResourceGroupTitle>Free Content</ResourceGroupTitle>
+<BadgeLink colorScheme='blue' badgeText='Official Website' href='https://www.cloudflare.com/learning/dns/dns-records/dns-spf-record/'>What is a DNS SPF record?</BadgeLink>
+<BadgeLink badgeText='Watch' href='https://www.youtube.com/watch?v=WFPYrAr1boU'>SPF Overview</BadgeLink>