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href="https://uptimerobot.com/blog/category/glossary/" rel="category">Glossary</a></span> <span class="post-category"><a href="https://uptimerobot.com/blog/category/port-monitoring/" rel="category">Port monitoring</a></span> </div> <div class="post-title"> <h2> <a href="https://uptimerobot.com/blog/understanding-smtp-monitoring/">SMTP Monitoring Uncovered: How Does It Work?</a> </h2> </div> <div class="post-excerpt"> <p>SMTP, which stands for Simple Mail Transfer Protocol, is a crucial component in the world of email communication. It’s a protocol used within the TCP/IP suite that facilitates the sending and receiving of email. SMTP is commonly used by a range of email clients such as Gmail, Outlook, Apple Mail, and Yahoo Mail. As of […]</p> </div> <div class="post-meta"> <div class="post-author"> <img alt='' data-src='https://uptimerobot.com/blog/wp-content/uploads/2024/04/diana.jpeg' srcset='https://uptimerobot.com/blog/wp-content/uploads/2024/04/diana.jpeg 2x' class='avatar avatar-32 photo' height='32' width='32' loading='lazy' decoding='async'/> <span class="author-name"> <a href="https://uptimerobot.com/blog/author/diana/"> Diana Bocco </a> </span> </div> <div class="post-date"> November 30, 2023 </div> </div> </li> <li class="post-item"> <div class="post-categories"> <span class="post-category"><a href="https://uptimerobot.com/blog/category/glossary/" rel="category">Glossary</a></span> <span class="post-category"><a href="https://uptimerobot.com/blog/category/observability/" rel="category">Observability</a></span> </div> <div class="post-title"> <h2> <a href="https://uptimerobot.com/blog/sla-slo-sli/">SLA vs. SLO vs. SLI: What’s the Difference?</a> </h2> </div> <div class="post-excerpt"> <p>When it comes to managing services effectively, terms like SLA, SLO, and SLI are often thrown around like confetti at a parade. They’re in meetings, in documents, and even in casual office conversations. But if you’re new to the field or simply haven’t had the chance to dig into these acronyms, they can feel like […]</p> </div> <div class="post-meta"> <div class="post-author"> <img alt='' data-src='https://uptimerobot.com/blog/wp-content/uploads/2024/05/laura.jpeg' srcset='https://uptimerobot.com/blog/wp-content/uploads/2024/05/laura.jpeg 2x' class='avatar avatar-32 photo' height='32' width='32' loading='lazy' decoding='async'/> <span class="author-name"> <a href="https://uptimerobot.com/blog/author/laura/"> Laura Clayton </a> </span> </div> <div class="post-date"> October 11, 2023 </div> </div> </li> <li class="post-item"> <div class="post-categories"> <span class="post-category"><a href="https://uptimerobot.com/blog/category/glossary/" rel="category">Glossary</a></span> <span class="post-category"><a href="https://uptimerobot.com/blog/category/website-monitoring/" rel="category">Website monitoring</a></span> </div> <div class="post-title"> <h2> <a href="https://uptimerobot.com/blog/999-status-code/">A Deep Dive into the HTTP 999 Status Code</a> </h2> </div> <div class="post-excerpt"> <p>As mentioned in our ultimate guide to HTTP status codes, HTTP 999 is unofficial, but it still plays an important role in the flow of our online journey in unexpected ways — and here’s why. So what is it for? We all know that the digital highway is held together by something called the Hypertext […]</p> </div> <div class="post-meta"> <div class="post-author"> <img alt='' data-src='https://uptimerobot.com/blog/wp-content/uploads/2024/05/laura.jpeg' srcset='https://uptimerobot.com/blog/wp-content/uploads/2024/05/laura.jpeg 2x' class='avatar avatar-32 photo' height='32' width='32' loading='lazy' decoding='async'/> <span class="author-name"> <a href="https://uptimerobot.com/blog/author/laura/"> Laura Clayton </a> </span> </div> <div class="post-date"> July 27, 2023 </div> </div> </li> <li class="post-item"> <div class="post-categories"> <span class="post-category"><a href="https://uptimerobot.com/blog/category/glossary/" rel="category">Glossary</a></span> <span class="post-category"><a href="https://uptimerobot.com/blog/category/website-monitoring/" rel="category">Website monitoring</a></span> </div> <div class="post-title"> <h2> <a href="https://uptimerobot.com/blog/http-status-codes-guide/">HTTP Status Codes Uncovered: Your Ultimate Guide</a> </h2> </div> <div class="post-excerpt"> <p>Did you like our previous blog about domain hijacking? Let’s see if you know all the HTTP codes now. Decoding HTTP status codes HTTP status codes, typically a sequence of three numbers, are a reply from the server in response to a request made by a web browser. A common example many might recognize is […]</p> </div> <div class="post-meta"> <div class="post-author"> <img alt='' data-src='https://uptimerobot.com/blog/wp-content/uploads/2024/05/laura.jpeg' srcset='https://uptimerobot.com/blog/wp-content/uploads/2024/05/laura.jpeg 2x' class='avatar avatar-32 photo' height='32' width='32' loading='lazy' decoding='async'/> <span class="author-name"> <a href="https://uptimerobot.com/blog/author/laura/"> Laura Clayton </a> </span> </div> <div class="post-date"> July 27, 2023 </div> </div> </li> </ul> </div> <div id="pagination" class="pagination"> </div> </div> </div> </div> </section> <!-- end last posts --> <footer class="footer"> <div class="container"> <div class="row"> <div class="col"> <div class="item"> <div class="logo"> <a href="/"> <img src="https://uptimerobot.com/blog/wp-content/themes/twenty-twenty-child/assets/img/uptimerobot-logo.svg" alt="UptimeRobot logo" /> </a> </div> <p><b>Downtime happens. 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