What is Cloud API Service Consistency Scoring (CASC)?
CASC scoring deals with one of the challenges of understanding what your Key Performance Indicators KPIs for APIs are telling you – how do you come to terms, easily and quickly with large amounts of data in a meaningful way. This has been recognized before with systems like Apdex, but these have been, generally, very simplistic approaches to dealing with the challenges of performance and quantifying it.
Building on the success of the ‘credit score’ in the financial sector, APImetrics have developed Cloud API Service Consistency (CASC) scoring to give a simple, at a glance, indication of the quality and health of a specific API or group of APIs and allow for easy, like-for-like comparisons between different systems.
A CASC score is a simple 3 digit number scored out of 999, the closer to 999 it is, the closer to perfect performance. Our scoring engine takes into account pass rates, error rates, outliers detected and the general consistency of performance – for example, it might be possible to have a slow API that scores well and a fast API that scores poorly due to inconsistent performance.
This article outlines the key features and benefits of using CASC to measure your critical APIs.
What is a CASC score?
Simply put, you don’t want to know just that your API is performing. You also want to know HOW it is performing. Our CASC Score is a number between 0 and 1000 that tells you how well an API performed over a period of a week or a month.
You can see at a glance how an API is behaving and how this compares to any other measured API, whether one of your own or that of your suppliers, your partners, and customers.
The higher the CASC Score, the better. If your CASC Score is higher this week compared to last week, you know your API is getting better. If it’s lower, you know your API is getting worse.
Most APIs are good APIs. A CASC Score of over 800 indicates few if any issues. Between 400 and 800, there are some issues that need to be looked at. And below 400? That means you are using or exposing a bad API that has very serious problems that need to be resolved as soon as possible.
And the CASC Score is an easy and transparent way of measuring whether an API is meeting its Service Level Agreement. Simply specify a CASC Score that the API must meet. If it’s higher than that for the period you’re interested in (a week or month), you know the SLA has been met.
How do we do it?
Think of the CASC Score as a bit like a credit rating. We take all of the metrics we have for each API, blend them together, then compare the result against our unrivaled dataset of historical API test records. This gives us a single number that is automatically benchmarked against all the other APIs monitored by APImetrics.
As for how we do the blending and the benchmarking, well, that’s our little secret! You don’t expect Coke or KFC to give away their recipe, do you? But let it be understood that it does involve state of the art machine learning technology.