The Akamai Global Traffic Management (GTM) has an optional feature called load feedback. With load feedback, load balancing is controlled by measurements of entities, which you define, called resources. GTM names are grouped by domain (for example, example.akadns.net). Within a domain, you may have any number of properties, or fully qualified names (e.g., images.example.akadns.net). Network traffic is balanced between data centers, also known as regions or traffic targets.
A resource is anything that is consumed by load on a data center, and is measured and reported to improve load balancing. As an example, for a database application, you might decide that the most important measurement of load is queries per second. For a static web server, you might choose to measure HTTP GET requests per second. A resource is simply a name for something you measure that reflects how you want to balance load across your datacenters. You report the load in whatever units make sense to you; to GTM, loads are just relative unit-less quantities. A resource may constrain a single property, or all properties in a domain.
An instance of a resource represents the current, target, and maximum load configured for a particular data center.
For a full description of GTM, our DNS-based load balancing, and all the terms used here, please see Global Traffic Management and Global Traffic Management API.