4. Conclusion

The methods for inter AS VPN are fairly tried-and-tested, and all well known and deployed. They are highly dependent on the type of network to be connected (single-operator or multi-operator) and the resulting selection criteria (security, QoS, management). Scaling up can also change the choice, for example, because of the difficulty of deploying complex configurations in the case of large networks with many VPN sites to interconnect.

However, it is not uncommon for an operator to choose to deploy several types of solution, depending on the networks with which it connects. For example, they may choose option A when security issues are most important, and option C with a similar operator in whom they have a very high level of trust, to enable scaling and simpler configuration.

New inter AS VPN techniques are unlikely to emerge from future...