An Automatically Switched Optical Network (ASON) is an "intelligent" optical network that can automatically manage the signalling and routing through the network. Traditionally, it was necessary to configure cross-connections in the Network Elements (such as an optical switch) to create a new traffic path for a customer.
In an ASON, this process can be automated. The customer defines a new path by its start and end point, the bandwidth needed, the Quality of Service and so on. The Network Elements have the necessary processing functions built in to configure the new traffic path. The path itself is not specified by the customer. The ASON network creates a light path through the network for this customer. This traffic path will be changed if the network is changed.
ASON uses the Generalized MPLS (GMPLS) signalling protocol to set up and monitor edge-to-edge transport connections. ASON concentrates on the optical backbone network. The related ASTN is used in the access networks and metropolian area networks, so called city rings.
Switching technologies used in ASON range from simple fiber switching to wavelength (λ) switching to optical packet switching. The components required for the switching are optical cross connects (OXCs), wavelength converters and optical add/drop multiplexers (OADMs).
Dynamic signalling-based policy-driven control over OTN and SDH networks via a distributed (or partially distributed) control plane that provides auto-discovery and dynamic connection set-up. This enables: Improved support for current end-to-end provisioning, re-routing and restoration New transport services such as bandwidth on demand, rapid service restoration for disaster recovery, switched connections within a Private Network, etc. Support for a wide range of narrowband and broadband clients signals such as:
SDH/SONET
IP Ethernet
ATM
Frame Relay
ESCON, FICON,
Fibre Channel
Audio/Video
