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CompTIA Network+ 1.4 Cisco CCST Networking 1.5
TechKnowSurge Catalog Interactives Which Protocol Moves This Email Step?
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Which Protocol Moves This Email Step?

Which protocol handles each step of email?

⚑ Complete this interactive to capture a CTF flag worth 5 points.

About this interactive

From the lesson: - **SMTP (TCP 25; secured forms preferred):** a push, from the user agent to the submission agent, to the transfer agent, to the recipient's mail exchanger and on to the delivery agent. - **DNS:** the transfer agent looks up the recipient domain's **MX record** to find where to send. The receiving server can look up the sending domain's **SPF record** to see whether the sending server is allowed to send for it. - **POP3:** the client pulls mail down; the server copy is removed unless the client is set to leave one. Folders made on the client are not reflected on the server. - **IMAP:** a two-way sync between the client and the delivery agent, so folders, moves and read status match on every device. - **Webmail:** the mailbox in a browser, over HTTPS.

What you'll learn

Aligned to

CompTIA Network+
1.4 Explain common networking ports, protocols, services, and traffic types.
Cisco CCST Networking
1.5 Describe common network applications and protocols

Key terms

Simple Mail Transfer Protocol
SMTP
A TCP-based application-layer protocol used to send email messages between mail servers and from mail clients to outbound mail servers, typically on port 25 (server-to-server) or port 587 with TLS (client submission). SMTP only handles sending mail; retrieval is handled by separate protocols such as IMAP or POP3.
Post Office Protocol version 3
POP3
A TCP-based email retrieval protocol that downloads messages from a mail server to a local client, operating on port 110 (insecure) or port 995 (over SSL/TLS).
Internet Message Access Protocol
IMAP
A TCP-based email protocol that provides dynamic synchronization between a mail server and client, operating on port 143 (insecure) or port 993 (over SSL/TLS).
MX Record
A DNS record type that specifies the mail exchange server responsible for receiving email for a domain.
SPF Record
A DNS TXT record that specifies which mail servers are authorized to send email on behalf of a domain.
Mail Transfer Agent
MTA
A server component responsible for routing and relaying email messages between servers by performing DNS MX record lookups to determine the destination.
Mail Delivery Agent
MDA
A server component that receives email from a mail transfer agent and stores it in the recipient's mailbox until retrieved.

Topics

Email Smtp Pop3 Imap Spf Mx Record Interactive Categorize

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