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What is Simple Mail Transfer Protocol (SMTP)?

About Simple Mail Transfer Protocol (SMTP)

Simple Mail Transfer Protocol (SMTP) is a standard protocol used for transmitting email messages across the internet. It works by allowing email clients to send messages to mail servers and mail servers to relay messages to other mail servers. SMTP operates on port 25 by default and follows a set of rules for communication between servers. It is responsible for the delivery of outgoing mail from a sender's email client to the recipient's email server.

Advantages

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    Reliable delivery: SMTP ensures reliable delivery of email messages by following a standardized protocol for communication between email servers.

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    Compatibility: SMTP is widely supported by email clients and servers, making it compatible with various email platforms and systems.

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    Authentication: SMTP supports authentication mechanisms such as SMTP-AUTH, which helps prevent unauthorized access and misuse of email services.

Cons

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    Security risks: SMTP lacks built-in encryption, making it vulnerable to interception and unauthorized access to email content.

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    Spam and phishing: SMTP's open nature can be exploited by spammers and phishers to send unsolicited or malicious email messages.

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    Delivery delays: SMTP relies on the availability and proper configuration of mail servers, which can result in delays in message delivery.


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