80% of enterprise software is running on SaaS. The majority of users access these from outside the corporate network. How can you troubleshoot poor SaaS performance to maintain their productivity and make sure your business processes keep running smoothly?
Let’s take a first look at what drives SaaS performance and then take a closer look at how you can run diagnostics that help you draw a path towards resolution.
The drivers of SaaS performance
The response time experienced by end users from SaaS platforms is driven by multiple infrastructure and application layers: endpoint, local network / WiFi, DNS, ISP, internet path, cloud secured gateways, 3P/CDNs, cloud platform and application response.
Endpoint health
The performance of the end user’s machine obviously has an impact on the response times perceived by the user in the sense that it will affect the sequence and speed of interaction with the different servers delivering the application (data, images, scripts, …), the rendering on the browser and the execution of the local javascripts.
To run properly, that machine will need sufficient resources (processor, memory, disk) for the browser to execute all these tasks efficiently.
The browser used to access the SaaS applications may also have an impact on the speed of rendering of the application to the user.
Local network and WiFi
The performance of the local network (from the location of each end user) materialized as the latency, packet loss and bandwidth available to the router may harm the performance of all web applications. WiFi coverage issues, poor quality LAN will negatively impact the experience of users, as it would impact all transactions strongly.
DNS (Domain Name System)
That system translates hostnames (or FQDN) into IP addresses so that the request can be routed to the adequate nodes.
DNS will affect SaaS performance in two ways:
- Resolution time: unless the DNS resolution has been performed and cached recently, translating a hostname into an IP address takes some time (making a request to a DNS server, waiting for the DNS processing to be performed and the response to be transferred back to the client). DNS has a huge impact in case of unavailability, on the other hand the DNS resolution time will affect SaaS performance in a limited way as it will only add delay when a new session is started and the DNS resolution is not found in cache.
- According to DNS service providers name servers locations and availability, DNS resolutions are performed based on a geolocation of users and used to redirect them to the closest host for each service. An error in geolocation can strongly affect response times by adding network latency to all interactions with the applications for both the server processing and the data transfer.
Network latency from the users to the SaaS platform
The time needed to send packets back and forth between the user and the servers will affect all steps in using the app: establishing a TCP session, setting up a secure TLS connection (see this article for more details on this), making requests to the server, and receiving server responses.
Network latency should be considered not only to the application root servers but also to all hosts involved in the delivery of the application (CDN, authentication servers, API, third-party services). To understand more about this topic, I recommend you take a look at this article.
Cloud gateways and proxy servers
Most enterprise IT departments have taken measures to secure the access to their SaaS applications for work from home situations. They use a variety of cloud services ensuring authentication, access rights enfor