Internet VPNs | ISGMLUG

Welcome to our SGML and XML Resource site

Internet VPNs

An internet VPN can provide a secure way to move data packets across the web if you have the right equipment. There are two basic methods for doing this.

Transport Mode – which is the technique of encrypting only the payload section of the IP packet for transport across the internet. Using this method the header information is left entirely intact and readable by hardware. This means that routers can forward the data as it traverses the internet.

Tunnel Mode – Using this method-IP, SNA, IPX and other packets can be encrypted then encapsualted into new IP packets for transporting across the internet. The main security advantage of this method is that both the source and destination addresses of the original packet are hidden and not visible.

With either case, Internet VPNs trade off the reliability and guaranteed capacity which are available using frame relays or ATM virtual circuits. However the comparative low cost of these internet VPN products make them really popular. You can get low cost UK based VPN for example at a very low costs. Most of the VPN service providers, have recognised the concerns around security and have made security and privacy a priority with product development.

Encryption obviously provides some level of security, however the other layer needed is secure authentication. It is essential that secure authentication protocols are used to ensure that the people or devices at each side of the link are authorised to use the connection.

There are numerous scenario types to these internet VPNs however most commercial ones come into two distinct groups. The first is the site to site connection, which is designed to tunnel large amounts of data between two specific sites. The second relate to virtual services which are usually dial up type connections from individual users generally into a corporate site.

Both of these method will normally both use a local connection into an ISP with the wide area sections covered by the internet. They are distinct options and will be used in very different circumstances. The ‘personal vpn’ market is growing every year particularly due to the increasing filtering and censorship which is becoming standard ion the internet. Using a VPN allows you to both avoid privacy issues but also to avoid the filters and blocks. In China a huge number of people use these services because of the increasing number of blocks employed by the Chinese State.

Harry HAwkins
Website here


  • Recent Posts