Application Programming Interface – a connector between different software systems
Service
A software service delivered via cloud APIs
Cloud
Distributed computing service using server resources from providers such as Amazon, Microsoft, Google and IBM
AWS
Amazon Web Services
Azure
Microsoft Cloud Services
Google
Google Cloud Compute
IBM
IBM Cloud Services
DNS
Domain Name Service – the global system that allows the internet to identify the location of a specific internet service via a human readable name
Latency
The time a specific action takes to complete – usually measured in milliseconds – 1 millisecond is 1/1000 of a second - to understand this in human terms, a normal camera flash lasts 1 millisecond and light itself can travel about 300 km (186 mi) in that time.
CDN
Content Delivery Network – used by IT systems to optimize the performance of their APIs and Websites
Median
The mid-point value in a data collection
Mean
The average value of data in a collection
Total API Call Time
Used in this document to relate to the entire sequence of making an API call from DNS name lookup, through connection, security handshakes, to the point at which the final result is returned
HTTP
Hyper Text Transfer Protocol – the basic communication system for the internet and APIs
HTTP Status Code
A standard set of codes used by computer services to identify what is happening
HTTP 200 codes
Generally indicates a passing result (but not always!)
HTTP 400 codes
Indicates that something has gone wrong somewhere but the API call has not necessarily failed – these often relate to security codes expiring – but can also indicate that another system has failed. These can be misleading and with API transactions can often indicate other problems
HTTP 500 codes
A failure has occurred – either an error code from the service itself, or an indication that something is not working in the back-end infrastructure or that a service is down for some reason