The architecture in which the database resides on a back-end machine and users access data through their workstations is

Client-server

Explanation: The client-server model is a type of model or architecture in which a client (Customer) requests for services from another known as the server which serves as the service provider.

In the client-server architecture, the database resides in the back end machine, from where services can be rendered to the client or users.

Client-Server Model

Explanation:

The Client-Server model structure divides tasks between clients, which are the the requesters of services, and servers, which are the providers of services or resources.

Information or data, is usually stored securely in the backend or server machine. Users then access these information by communicating with the server over a computer network.

Example is when a user requests a webpage using a website's address. The server gets the request from the client and finds the page in the database residing in the backend, then serves it up to the user when found.