Virtual Private Networks, Second Edition

Delivering Quality of Service

We have already spoken about QoS in reference to choosing an ISP. This section will discuss creating QoS for your own connectivity. QoS gives you the ability to manage your bandwidth. It does this by allowing you to assign priorities to certain types of network traffic based on user, application, host, network, or protocol. With a VPN, you might be using your VPN Internet connection for normal Internet traffic as well, such as email, web browsing, file transfers, etc. Since a VPN connection is business-critical, you might want those users to have less latency time compared to some other services. In this case, you could bump up the priority of your VPN traffic, while lowering the priority of traffic that is not necessarily business oriented, such as PointCast, NNTP, or access to certain URLs.

The Resource Reservation Protocol (RSVP) is a proposed Internet QoS standard that can be used to manage IP traffic. It is already available on some routing and VPN equipment, and some operating systems. In addition, there are a number of bandwidth management products available from vendors such as Packeteer and Check Point.