Logical and Physical Design of a Network

The difference between logical and physical design of a network is simple. The idea of a network is the logical design. It deals with a logical topology for the new or enhanced network, network layer addressing, naming, and switching and routing protocols. Logical design also includes security planning, network management design, and the initial investigation into which service providers can meet WAN and remote access requirements. The physical design involves the specific technologies and products to realize the logical design. Basically it involves the actual devices that will be used in order to get the logical design to work.

Businesses need to sometimes increase the size, upgrade the hardware, or install a brand new network. In order to do this successfully, they need to sit down and think of what sort of network design will help in meeting these business or customer requirements. Good network design must recognize that a customer's requirements embody many business and technical goals including requirements for availability, scalability, affordability, security, and manageability. Many customers also want to specify a required level of network performance, often called a service level. To meet these needs, network design choices and tradeoffs must be made when designing the logical network before any physical devices or media are selected.

A network is a way to connect two or more devices together so that they can exchange information. In order to make this work, each device must know when another is trying to connect to it and it must know how to reply. The network consists of a whole suite of protocols to make this work.

A logical layout or logical design shows all logical aspects of the network. This includes logical networks, assigned IP addresses to various hosts and devices, routing tables and a lot more. In logical diagrams, there is very little interest in the actual interfaces and physical cables, so these details are usually omitted.

A physical layout of a network shows the physical location of and the connections between devices participating on the network. In such diagrams, workstations are usually represented with small computer icons, servers with full tower cases, and switches and other similar devices.

At the most basic level, the wire is used to make the physical connection. In most cases this will be designed for an Ethernet type physical network. Fiber optic cable is just a single