Résumé: Large IP networks usually combine protection and restoration mechanisms at various layers of the protocol stack to minimize service disruption in the event of failures. Sprint has chosen an IP-based restoration approach for building a highly available tier 1 IP backbone. This article describes the design principles of Sprint's network that makes IP-based restoration an effective and cost-efficient approach. The effectiveness of IP-based restoration is evaluated by analyzing network failure characteristics, and measuring disruptions in service availability during controlled failure experiments in the backbone. Current trends for improving the performance of IP-based restoration are also discussed.

Langue: Anglais