Installation guide

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FURTHER INFORMATION
Virtual Private Network
Sometimes it may be useful to extend your private network outside your practice building – for example, to
connect to a branch surgery, to access your practice network from home or while travelling, or from the local
hospital.
In most cases, it is not be possible to extend your Ethernet cables to that other location. Sometimes, when
there is line of sight, a wireless link might be feasible, but usually distances and geography do not allow this.
However, as long as both locations can connect to the Internet, they can also connect to each other. Since
the Internet is a public place, you have to take some precautions to keep your private network traffic private.
To do this, you have to create a Virtual Private Network (VPN), or a secure tunnel through the Internet.
On a properly configured VPN, you don't have to distinguish between your local and the remote network.
For practical reasons, especially regarding privacy, they can be considered as a single cabled network.
This is achieved by strongly encrypting all network packets flowing between the two private locations. In the
ideal case, this is done transparently by a ‘VPN router’, which is a device that automatically encrypts all
traffic flowing from local to remote, and automatically decrypts all traffic flowing from remote to local.
Such device guarantees that all traffic flowing through the Internet between the two VPN endpoints is kept
strictly confidential, regardless of what software is used on these computers (e.g. email, word processor
etc.).
Figure 6: A VPN router transparently encrypts and decrypts network traffic
There are many different protocols available for VPN implementation. However, for the time being, only
consider the international Internet standard protocol, called IPSec.
Microsoft initially had its own VPN protocol, called PPtP. However, it is considered insecure and should
never be used in a medical practice setting. For this reason, do not use any of the VPN routers available
which are only capable of PPtP instead of
IPSec.
The most common scenario for a VPN might be linking two branch surgeries together. As depicted in Figure
7, this can be achieved easily through two properly configured and compatible VPN routers. Nothing needs
to be changed software-wise on any of the computers in either practice.