VPN using the public network building is a new network concept, which for service providers and VPN users will bring many benefits. For businesses, the private network using Internet set up, green fees can be reduced to a large city, then a small amount of fees and Internet fees, related news analysis, only the LAN interconnection costs can be reduced by 20% to 40%, while the remote access Fees can reduce 60% to 80%; for service providers, through the VPN to provide value-added services more closely with enterprises to establish relations of cooperation, make full use of existing network resources and improve the business volume. Virtual private network is a network built using public private private network technology, used to build a public network, including VPN Internet, Frame Relay, ATM and so on. "Virtual" concept is relatively traditional in terms of private networks are built, for wide area network connections, the traditional dial-up networking to achieve through the remote, while the VPN is provided by service providers to realize the remote public network WAN connection. Through the VPN, enterprises can lower the cost of connecting remote offices, business professionals and business partners.
The Web program, the only stress some simple Javascript. Web programs can also be from the new Web standard technology to benefit, such as HTML5, CSS3 and so on. However, Javascript, a programming language to provide all these elements into the Web site, not just show something. JavaScript is not only competition existed in the past, it has gradually in a number of network programming in the popular. Such as Yahoo Mail, people can click on the message, drag it to the folder. This high-end Javascript technology called Ajax. Beltzner said: "A few years ago, people began to accept the new JavaScript-centric development model, programmers want to let the browser handle more things." 2008, Javascript engine has become the focus of competition in the browser field. June, Webkit released SquirrelFish engine, and then SquirrelFish Extreme also appeared. Firefox8 month released TraceMonkey, Google9 month with the release of the Chrome V8, Opera released in February this year, Carakan, this month, Apple released the Safari 4 beta in a Nitro engine.