Diagram of a sample application

VPN Application
The traditional corporate WAN is based on dedicated links between locations and perhaps a connection to the internet at head office. As internet use increases, the private WAN carries more and more internet traffic, increasing costs and reducing performance. VPN turns this around. Connect every site to the internet and tunnel your private traffic through the internet. The savings can be enormous especially for international links.
LAN to LAN VPN relies upon a VPN server at each branch. The branches then form a meshed network or a hub and spoke network of tunnels connecting each other through the internet. Some issues to consider:

o    get a fixed IP address for each site
o    consider manual key for modem links if IKE does not negotiate
o    large fully meshed networks are hard to maintain with static routes
o    consider policy based management tools

Use the Internet for remote access
A long distance call for remote access is expensive and from many parts of the world performance is miserable. Why not dial a local ISP anywhere in the world and connect back to the office through the internet? A VPN connection is authenticated and encrypted to give you more security than direct dial. The cost savings can be enormous.
Client VPN connects individual PCs via the Internet to a central location. Home users with broadband will get much better performance than direct modem dial up. Many nice features are vendor specific. Consider:

o    which protocol? Our preferred protocol is IPsec
o    consider IP address allocation - pool vs DHCP
o    how to authenticate users? Password, certificate, proxy to NT or NDS?
o    split tunnelling - allowing a user to connect to the internet and the tunnel saves costs but may be a security risk
o    personal firewall
o    cost of client software
o    global roaming access through a service such as iPass

Corona IT can tailor to the corporate needs ,and will provide and select best VPN solution for Corona IT's client