Vanguard Managed Solutions Vanguard 342 Benutzerhandbuch

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About the Vanguard 342
Target Applications
Virtual Private Network 
Introduction
This section provides a general description of features and applications within the 
Vanguard Virtual Private Network (VPN). 
These topics are discussed:
For detailed information about a VPN, refer to your Virtual Private Network Manual 
(Part Number T0103-10).
What is a VPN?
A Virtual Private Network (VPN) is a network that has the appearance and many of 
the advantages of a dedicated link but occurs over a shared network. Using a 
technique called “tunneling,” packets are transmitted across a public routed network, 
such as the Internet or other commercially available network, in a private “tunnel” 
that simulates a point-to-point connection. 
This approach enables network traffic from many sources to travel through separate 
tunnels across the same infrastructure. A VPN allows network protocols to traverse 
incompatible infrastructures. A VPN also enables traffic from many sources to be 
differentiated, so that it can be directed to specific destinations and receive specific 
levels of service.
Advantages of a 
VPN
A VPN provides following advantages:
• Cost Effectiveness
Infrastructure Cost - By using a VPN, a company need not invest money 
on connectivity equipment like leased lines, WAN switches etcetera. The 
connectivity is provided by the service provider.
Operational Cost - Costs involved with maintaining leased lines or a 
private WAN along with the money spent on people to maintain them can 
be avoided.
• Manageability
- A VPN is more easily managed when compared to a fully private network.
Requirements of a 
VPN
Below are some of the requirements of a VPN:
• Connectivity
- There needs to be network connectivity among the various corporate sites. 
This connectivity is typically used through the Internet.
• Security
- Data exchanged between the various corporate sites is confidential. When 
data is sent over a public network it is usually encrypted. The encryption 
algorithm must be robust enough to withstand any type of snooping.