It is a trend of virtual private networks (VPNs) to be used for information exchange between enterprises, branches of enterprises and enterprises and their employees instead of traditional dial networks and leased lin...It is a trend of virtual private networks (VPNs) to be used for information exchange between enterprises, branches of enterprises and enterprises and their employees instead of traditional dial networks and leased lines. The tunneling technique is the key technique to implement VPN. In this paper, with the VPN implementation requirements in mind, we perform a comparative research on the existing tunneling protocols including GRE, L2TP, IPSec and IP/IP. We also propose an integrated scheme of tunneling mechanism that supports VPN under the current condition.展开更多
This article describes how to utilize the VPN to construct the new Extranet’s topology. Firstly, it tells what is the Extranet. Secondly, some basic principles and technical idioms of the VPN are dealt with. Thirdly,...This article describes how to utilize the VPN to construct the new Extranet’s topology. Firstly, it tells what is the Extranet. Secondly, some basic principles and technical idioms of the VPN are dealt with. Thirdly, tunnel protocols about VPN are discussed. Finally, three kinds of Extranet’s architectures with VPNs are given. Through integrating the VPNs into the Extranet, we can get much more benefits from shared networks (e.g., Internet, ISDN, PSDN, etc.).展开更多
West-to-East gas pipeline project is the largest project undertaken by PetroChina since the company issued IPO at international capital markets in 1999.Construction of West-East gas pipeline is of great strategic sign...West-to-East gas pipeline project is the largest project undertaken by PetroChina since the company issued IPO at international capital markets in 1999.Construction of West-East gas pipeline is of great strategic significance to secure PetroChina's leading position in the domestic natural gas market, turn the company's advantage in resources into benefits and make the natural gas business a new growth point for the company. Meanwhile, the project will benefit the economic development in China's western region,Xinjiang area in particular, improve the energy structure in the natural gas consuming regions and atmospheric environment in the areas along the pipeline and raise the general living standards.展开更多
文摘It is a trend of virtual private networks (VPNs) to be used for information exchange between enterprises, branches of enterprises and enterprises and their employees instead of traditional dial networks and leased lines. The tunneling technique is the key technique to implement VPN. In this paper, with the VPN implementation requirements in mind, we perform a comparative research on the existing tunneling protocols including GRE, L2TP, IPSec and IP/IP. We also propose an integrated scheme of tunneling mechanism that supports VPN under the current condition.
文摘This article describes how to utilize the VPN to construct the new Extranet’s topology. Firstly, it tells what is the Extranet. Secondly, some basic principles and technical idioms of the VPN are dealt with. Thirdly, tunnel protocols about VPN are discussed. Finally, three kinds of Extranet’s architectures with VPNs are given. Through integrating the VPNs into the Extranet, we can get much more benefits from shared networks (e.g., Internet, ISDN, PSDN, etc.).
文摘West-to-East gas pipeline project is the largest project undertaken by PetroChina since the company issued IPO at international capital markets in 1999.Construction of West-East gas pipeline is of great strategic significance to secure PetroChina's leading position in the domestic natural gas market, turn the company's advantage in resources into benefits and make the natural gas business a new growth point for the company. Meanwhile, the project will benefit the economic development in China's western region,Xinjiang area in particular, improve the energy structure in the natural gas consuming regions and atmospheric environment in the areas along the pipeline and raise the general living standards.
