Networks Work

When referring to a 'logical' network we are talking about the logical addressing used to describe the network itself or the networks it connects to. A logical network layout clearly shows the IP Addresses associated with each part of the network. One of the most important steps when designing a logical network is the future growth and expansion, a point that most people tend to overlook and face problems such as running out of available IP Addresses. When I design a network, I always leave room for an addition 50-60% growth of its current size.

Coming to the second part of your question, the Physical design, it refers to the actual layout of the physical part of our network. This includes the cables, switches, workstations etc. A physical layout/map usually involves a diagram of the actual floor the way it would be seen if you were on the ceiling, looking down towards to the floor. The classical physical design of most networks involve a central rack located in a computer room or a restricted access room where all wiring from the walls terminate and connect at the back of a patch panel. From the front side of the patch panel, UTP cables run directly to the switch, interconnecting all network devices. This topology is also known as a "star" topology since all devices connect to a central hub/switch. The physical design also defines the type of cable used to connect all devices, e.g Cat 5, Cat 5e or Cat 6, and the distances the devices will have from the switch. There are various topologies you can employ when designing and creating a local area network (LAN), and we also looked at some scenarios in which several networks were connected to form a wide area network (WAN). The physical aspects of your LAN will depend on the underlying physical transport technology--Ethernet or Token-Ring, for example, or possibly ATM, which is now supported in products such as Windows 2000/XP and Server 2003 as a LAN protocol. Depending on which technology