Definitions

Table Of Contents

• What is Restful Web Service ?
• REST Architecture Principles
• What are Network Devices ?
• What is a Graph ?

What is Restful Web Service ?

"Restful Web Services is a lightweight, maintainable, and scalable service that is built on the REST architecture. Restful Web Service, expose API from your application in a secure, uniform, stateless manner to the calling client. The calling client can perform predefined operations using the Restful service. The underlying protocol for REST is HTTP." [1]

REST Architecture Principles

REST (REpresentational State Transfer) is a set of architectural constraints, not a protocol or a standard.

In order for an API to be considered RESTful, it has to conform to the following criteria [2] :

"1. Client-Server: This constraint operates on the concept that the client and the server should be separate from each other and allowed to evolve individually."

"2. Stateless: REST APIs are stateless, meaning that calls can be made independently of one another, and each call contains all of the data necessary to complete itself successfully."

"3. Cache: Because a stateless API can increase request overhead by handling large loads of incoming and outbound calls, a REST API should be designed to encourage the storage of cacheable data."

"4. Uniform Interface: The key to the decoupling client from server is having a uniform interface that allows independent evolution of the application without having the application’s services, or models and actions, tightly coupled to the API layer itself."

"5. Layered System: REST APIs have different layers of their architecture working together to build a hierarchy that helps create a more scalable and modular application."

"6. Code on Demand: Code on Demand allows for code or applets to be transmitted via the API for use within the application."

What are Network Devices (Element) ?

"Hardware devices that are used to connect computers, printers, fax machines and other electronic devices to a network are called network devices. These devices transfer data in a fast, secure and correct way over same or different networks. Network devices may be inter-network or intra-network. Some devices are installed on the device, like NIC card or RJ45 connector, whereas some are part of the network, like router, switch, etc" [3]

What is a Graph ?

"A graph (sometimes called an undirected graph to distinguish it from a directed graph, or a simple graph to distinguish it from a multigraph is a pair

G = (V, E), where V is a set whose elements are called vertices (singular: vertex), and E is a set of paired vertices, whose elements are called edges (sometimes links or lines).

The vertices x and y of an edge {x, y} are called the endpoints of the edge. The edge is said to join x and y and to be incident on x and y. A vertex may belong to no edge, in which case it is not joined to any other vertex." [4]