Call setup systems and methods using dynamic link tagging and overbooking of links in multi-domain transport networks

摘要

Call setup methods in a multi-domain network and a multi-domain network use dynamic link tagging and/or overbooking of External Network-Network Interface (ENNI) links. Thus, improved call setup systems and methods include two approaches to improve upon the responsiveness of the network for connection setups including bandwidth reservation in optical networks using “dynamic link tags” and link overbooking in optical networks based on a greedy approach. The bandwidth reservation and the link overbooking can be utilized together or separately to improve call setup. Advantageously, the improved call setup systems and methods can provide a generic bandwidth reservation mechanism, such as in Automatically Switched Optical Network (ASON) networks, to overcome the limitation of ENNI in concurrently updating the abstract link bandwidth and thereby improving the responsiveness of the network.

主权项

1. A call setup method in a multi-domain network, comprising:
receiving, at a routing controller or a central server, an abstract link configuration request between two border nodes in a domain of the multi-domain network with a plurality of associated parameters; determining a path for an abstract link in the domain based on the abstract link configuration request; generating a unique tag identifier, through a routing controller, for the determined path; flooding the determined path in the domain with the associated unique tag identifier to reserve Optical Channel Data Unit (ODU) bandwidth between the two border nodes for the call setup; creating the abstract link on the determined path such that the determined path is reserved based on the plurality of parameters; and operating an external network-network interface (ENNI) link connected to one of the two border nodes in an overbooked manner such that no call is failed until all of the resources on the ENNI link are actually used, wherein the operating comprises
responsive to a path message requesting bandwidth on the ENNI link and responsive to bandwidth being unavailable on the ENNI link for the path message, sending the path message with a blank upstream label and a new connection type so downstream nodes do not discard the blank upstream label,responsive to a reservation (RESV) message for the requested bandwidth, checking again if bandwidth is available on the ENNI link, andif bandwidth is available when the RESV message is sent, selecting the available bandwidth for the RESV message.