Virtual Local Area Network(VLAN's)

Virtual Local Area Networks or VLANs are one of the latest and coolest network technologies developed in the past few years, though have only recently started to gain recognition. The non-stop growth of Local Area Networks (LANs) and the need to minimize the cost for this expensive equipment, without sacrificing network performance and security, created the necessary soil for the VLAN seed to surface and grow into most modern networks.

Since Virtual Local Area Network that requires strong background knowledge of certain areas, as they contain a lot of information as the technical and protocol unit. i believe that the reader should familiar and comfortable with the following concepts:

• Switches and hubs
• Broadcast and collision domains
• Internet Protocol (IP)
• IP routing

Cabling

Early LAN cabling had always been based on various grades of coaxial cable. However shielded twisted pair was used in IBM's Token Ring implementation, and in 1984 StarLAN showed the potential of simple unshielded twisted pair by using Cat3—the same simple cable used for telephone systems. This led to the development of 10Base-T (and its successors) and structured cabling which is still the basis of most commercial LANs today. In addition, fiber-optic cabling is increasingly used in commercial applications. As cabling is not always possible, wireless Wi-Fi is now the most common technology in residential premises as the cabling required is minimal, and it is well suited to mobile laptops and smartphones.

LAN illustration.

The following characteristics are some advantages of LAN:

• Very high network speeds and data transfer rates
• Protection from the outside world, thus creating a trusted computing environment (Firewalls are usually used to protect LANs and to provide a secure computing environment.)
• No need to lease telecommunication lines, such as those used for telephone, data and Internet services, once the hardware for connecting all the machines has been bought