Traditional VPN's rely on IPSec (Internet Protocol Security) to tunnel between the two endpoints. IPSec works on the Network Layer of the OSI Model- securing all data that travels between the two endpoints without an association to any specific application. When connected on an IPSec VPN the client computer is "virtually" a full member of the corporate network- able to see and potentially access the entire network.
SSL VPN's have been gaining in prevalence and popularity; however they are not the right solution for every instance. Likewise, IPSec VPN's are not suited for every instance either. Vendors are continuing to develop ways to expand the functionality of the SSL VPN and it is a technology that you should watch closely if you are in the market for a secure remote networking solution. For now, it is important to carefully consider the needs of your remote users and weigh the pros and cons of each solution to determine what works best for you.
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