SMTP
About SMTP
Simple Mail Transfer Protocol, from RFC 821, routes email across the internet. Extensions added authentication, size limits and transport encryption via STARTTLS. Despite being four decades old it remains the universal email backbone, and SMTP port 25 still carries the world mailbox traffic.
Related Standards
IPv4
Internet Protocol version 4, defined in RFC 791 in 1981, has a 32 bit address space of about 4.3 billion addresses. The central...
IPv6
Internet Protocol version 6 expands addressing to 128 bits, providing roughly 340 undecillion addresses. Standardized through RFC...
TCP
Transmission Control Protocol, specified in RFC 793 with Vint Cerf and Bob Kahn as architects, provides reliable ordered delivery...
HTTP
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