Network Protocols

SMTP

SMTP (Simple Mail Transfer Protocol) is a standard internet protocol used for sending and relaying email messages between mail servers. It operates on TCP port 25 and defines the rules for communication between email clients and servers, handling message transmission, routing, and delivery. SMTP is a text-based protocol that uses commands and responses to manage email flow across networks.

Also known as: Simple Mail Transfer Protocol, SMTP Protocol, Email Protocol, Mail Transfer Protocol, RFC 5321

🧊Why learn SMTP?

Developers should learn SMTP when building applications that involve email functionality, such as sending notifications, newsletters, or transactional emails from web or mobile apps. It's essential for implementing custom email services, integrating with email marketing tools, or troubleshooting email delivery issues in production systems. Understanding SMTP helps ensure reliable email communication and compliance with email standards.

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Learning Resources

RFC 5321 - SMTP Protocol Specification

SMTP Tutorial by TutorialsPoint

SMTP Explained in 5 Minutes

Send Emails with SMTP in Python

Related Tools

Email Servers Email Clients Tcp Ip Dns Authentication Protocols

Alternatives to SMTP

Imap Pop3 Api Based Email Services

Other Network Protocols

Acme Protocol is a standardized communication protocol used for automated certificate management, primarily for obtaining and renewing SSL/TLS certificates from certificate authorities (CAs). It enables servers and applications to automatically request, validate, and install certificates without manual intervention, streamlining the process of securing web services with HTTPS. The protocol is widely implemented by CAs and tools like Let's Encrypt to support the ACME (Automated Certificate Management Environment) standard.

ActivityPub is an open, decentralized social networking protocol that enables servers to communicate and share social activities, such as posts, likes, and follows, across different platforms. It is a W3C standard that defines a client-to-server API for creating, updating, and deleting content, as well as a server-to-server API for federated interactions between independent servers. This allows users on different social media platforms to interact seamlessly, fostering interoperability in the fediverse.

ActivityPub is a decentralized social networking protocol that enables different social platforms to communicate with each other, allowing users to interact across independent servers. It provides a standardized way for servers to exchange social activities like posts, likes, and follows, forming a federated network where no single entity controls the entire system. This protocol underpins many modern federated social networks, promoting interoperability and user autonomy.

AMQP (Advanced Message Queuing Protocol) is an open standard application layer protocol for message-oriented middleware, enabling reliable, secure, and interoperable messaging between applications. It defines a wire-level protocol for message queuing, routing, and delivery, supporting features like publish/subscribe, request/reply, and point-to-point communication. AMQP is widely used in distributed systems, microservices architectures, and enterprise messaging to decouple components and handle asynchronous communication.

BACnet (Building Automation and Control Networks) is a communication protocol designed specifically for building automation and control systems, such as HVAC, lighting, and security. It enables interoperability between devices from different manufacturers by defining standard data objects, services, and network rules. Developed by ASHRAE, it is widely used in commercial and industrial buildings for efficient management and monitoring.

BACnet (Building Automation and Control Networks) is a communication protocol designed specifically for building automation and control systems, such as HVAC, lighting, and security. It enables interoperability between devices from different manufacturers by standardizing data exchange over various network types, including Ethernet, IP, and serial links. The protocol defines objects, services, and data structures to facilitate monitoring and control of building systems.