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courses/level101/metrics_and_monitoring/third-party_monitoring.md

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+##
+
+# Third-party monitoring
+
+Today most cloud providers offer a variety of monitoring solutions. In
+addition, a number of companies such as
+[Datadog](https://www.datadoghq.com/) offer
+monitoring-as-a-service. In this section, we are not covering
+monitoring-as-a-service in depth.
+
+In recent years, more and more people have access to the internet. Many
+services are offered online to cater to the increasing user base. As a
+result, web pages are becoming larger, with increased client-side
+scripts. Users want these services to be fast and error-free. From the
+service point of view, when the response body is composed, an HTTP 200
+OK response is sent, and everything looks okay. But there might be
+errors during transmission or on the client side. As previously
+mentioned, monitoring services from within the service infrastructure
+give good visibility into service health, but this is not enough. You
+need to monitor user experience, specifically the availability of
+services for clients. A number of third-party services such asf
+[Catchpoint](https://www.catchpoint.com/),
+[Pingdom](https://www.pingdom.com/), and so on are available for
+achieving this goal.
+
+Third-party monitoring services can generate synthetic traffic
+simulating user requests from various parts of the world, to ensure the
+service is globally accessible. Other third-party monitoring solutions
+for real user monitoring (RUM) provide performance statistics such as
+service uptime and response time, from different geographical locations.
+This allows you to monitor the user experience from these locations,
+which might have different internet backbones, different operating
+systems, and different browsers and browser versions. [Catchpoint
+Global Monitoring
+Network](https://pages.catchpoint.com/overview-video) is a
+comprehensive 3-minute video that explains the importance of monitoring
+the client experience.