As we have seen in the general introduction to web monitoring, external Web Monitoring uses third part tools running outside your own infrastructure to provide you with information on the availability and performance of your website. This means that this type of monitoring is capable of identifying problems on your infrastructure, the internet in general and the ISP('s) that host the probes or agents. External Web Monitoring does not replace your internal monitoring, it is complementary. Internal monitoring is primarily being used to monitor the availability of the various infrastructure components. The information is being used by your IT department of hosting provider to identify when components are struggling or failing. This kinf of monitoring does not provide you with information about the quality of service that your clients are experiencing and, in many cases, it can't even tell you if clients are actually capable of executing transactions or purchasing items. Internal Monitoring does not focus on the end-to-end application.
External Web Monitoring is not tracking any real user traffic. The probes can do very basic availability monitoring similar to Ping or do a very simple page load or they can simulate real users by executing multi pages transaction scripts. Monitoring is interval driven so that measurements are taken every hour, half hour, quarter or whatever interval you want. As a website will usually be monitored by multiple probes (on different geographical locations and ISP's), this can provide you with very granular data.
In general, you can distinguish three different types of external monitoring. Monitoring from proprietary probes where bothe the hardware and the software components are owned and managed by the vendor. Monitoring from cloud based probes where just the software is managed by the vendor and what we call desktop monitoring, where software probes are installed on desktops whose owners receive a small fee.
Each type has its own advantages and disadvantages. The first type provides the most consistent results as the probes are running on dedicated hardware and the performance of the probes will not be impacted by load from other applications sharing the same physical box. It is also perfect to monitor cloud based applications as you don't risk monitoring a website from the same cloud that it is running on.
Another advantage is that these vendors usually offer a large number of probes in many locations. The cloud based option is usually cheaper but has fewer locations and monitoring results will fluctuate because of performance variations on the probes or the cloud. The third options is usually the cheapest but it also offers the largest number of probe locations as many thousands of desktops may be used for probing. This type of service simply does not provide consistent data as the vendor cannot guarantee that the sames probes will always be used and measurement results will change significantly between individual probes because of different hardware, different connection speeds, additional programs running in parallel (Warcraft or Call of Duty for example...). Key Performance is offering external web monitoring from Keynote Systems that use either Keynote's own probes or cloud based locations. We don't offer the third type as it is simply not good enough.
Please be aware that the quality of an external monitoring service does not just depend on who owns and manages the hardware, the number of locations or if they differentiate between web and mobile. A lot depends on the technical quality of the probes (real browser or emulated, loading and execution of all page content or not), the depth of the data (full detail on all objects or just high level, full detail on each measurement or just summary data) and the quality of the reporting. It is true that the cost of different solutions and vendors differs a lot but in most cases these differences in cost can be justified by differences in technology, service, content and data integration capabilities.
Contrary to Internal Monitoring, which is in most cases fully owned by the IT department, External Web Monitoring is mostly owned by the business (product management, eBusiness team or marketing). The objective of external monitoring is to understand quality of service and the impact of it on customer behavior. Of course, the information is usually shared with IT and often used to plan performance optimisation activities to be executed by IT. Excellent websites are in most cases the results of a close cooperation between all stakeholders and a holistic, process driven approach.
Key Performance has many years of experience in this field and we have probably used most of the services that are available on the market during client projects. We are more than happy to help you select what solutions will best meet your requirements.