TAILIEUCHUNG - Networking: A Beginner’s Guide Fifth Edition- P31

Networking: A Beginner’s Guide Fifth Edition- P31:I have run into many people over the years who have gained good even impressive working knowledge of PCs, operating systems, applications, and common problems and solutions. Many of these people are wizards with desktop computers. | 132 Networking A Beginner s Guide corporate LAN. Even for users who don t have DSL or cable modems available in their area ISDN is usually an option from the local telephone company. ISDN and DSL technology are discussed in more detail in Chapter 7. Remote users using DSL or cable modems are hard-wired to a particular ISP for their connection so they need to use a virtual private networking approach to connecting to the LAN. ISDN users on the other hand have the choice of either connecting to an ISDN-capable ISP or to ISDN modems hosted on the LAN. Through a process called bonding ISDN users can achieve speeds up to 128 Kbps although this consumes two B-channels. and doubles the call charges Still such speeds are better than the Kbps that you can otherwise achieve through a modem. Virtual Private Networks A virtual private network VPN is a network link formed through the Internet between the remote user connected to an ISP and the company LAN. A VPN connection is carried over a shared or public network which is almost always the Internet. VPNs use sophisticated packet encryption and other technologies so the link from the user to the LAN is secure even though it may be carried over a public network. VPN connections cost much less than dedicated connections such as the WAN technologies discussed in Chapter 7 because they take advantage of the cost efficiencies of the Internet without compromising security. VPN solutions range from simple ones that can be implemented on a Windows server essentially for free using the Remote Access Service RAS included with Windows NT Server or the equivalent Routing and Remote Access Service RRAS in Windows 2000 Server or later to stand-alone specialized VPN routers that can support hundreds of users. Figure 10-6 shows how a VPN connection works. VPN connections are used in two important ways To form WAN connections using VPN technology between two networks that might be thousands of miles apart but which each have some way of .

• Quản trị mạng
• Kĩ thuật mạng
• Network
• tài liệu về Network
• sử dụng Network
• tạo Network
• giáo trình mạng máy tính
• mạng máy tính nâng cao
• thiết bị mạng
• thủ thuật internet
• hướng dẫn sử dụng internet
• tư liệu internet
• kĩ năng mạng
• thủ thuật windows office