 In addition, blades can be easily added. A specialized computer with a large hard drive. File servers provide users with access to documents and applications in central locations in LANs. The capability of equipment to balance traffic between networks and devices SO that one network or device is not overloaded while others carry little or no traffic. A group of devices such as computers, printers, and scanners that can communicate with one another within a limited geographic area, such as a floor, department, or small cluster of buildings. A switch located in a wiring closet that allows multiple simultaneous transmissions within a single LAN. Layer 2 switches provide a dedicated connection during an entire transmission. A switch that routes traffic across the LAN backbone based on IP (network) addresses. They are more complex to manage than Layer 2 switches, but they can use alternate paths if one path is out of service. They are located in data centers and link wiring closets and buildings within a campus. A switch located at hosting sites and corporate and government sites that host their own web pages. Layer 4 switches connect web traffic to the desired web pages by looking at the URL, the web address from which each packet was transferred to the site. www.TechnicalPDF.com Routers carry traffic between LANs, from enterprises to the Internet, and across the Internet. They are more complex than switches because they have routing tables with addresses and perform other functions. Routers select the best available path over which to send data. A centrally located computer with common departmental or organizational files such as personnel records, e-mails, sales data, price lists, student information, and medical records. Servers are connected to Layer 2 or Layer 3 switches. Access to servers can be restricted to authorized users only. A virtual local area network is made up of devices, usually personal computers or VoIP devices, whose addresses are programmed as a group in Layer 2 switches. This segregates them f