Category:Unique identifiersrepresent various schemes used to uniquely reference people, companies, and other things across domains, systems and organizations.
Unique identifieris an identifier that is guaranteed to be unique among all identifiers used for those objects and for a specific purpose.
today one request to a particular domain can involve a myriad of subsequent asynchronous requests from the starting domain to others.
For example, you send a request to Expedia, but behind the scenes Expedia is forwarding your request as a message to a message broker. Then that message is consumed by a hotel, airline and car rental agency that responds asynchronously too. So the question comes up, with your one request being passed about to a multitude of processing consumers, how do we keep track of the transaction? The answer is: use a Correlation ID.
Correlation IDs bundle one transaction as it moves through multiple processors.
You run an auction website that provides items from hundreds of sellers. Your visitor buys from three sellers in one order. Your website splits those orders to the disparate sellers. A week later, your client asks where the order is. A correlation ID could help you track all of the pieces that make up this one order.
if your workflows include sub-processors, assigning these unique numbers could help you provide optimal customer service.
A Correlation ID refers to an ID that uniquely links discrete events together across different services, which has a single origin.
For instance, a single user action, such as ordering an item, could generate multiple service calls.
A common approach to makes use of correlation IDs is to log the transaction in each service, collect logs, and transfer to a centralised logging solution.