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with Packet-aware Optical core network
efficiencies in the optical transport domain. These tunnels can be hitlessly resized as well, meaning as packet traffic grows or shrinks, the associated virtual wavelength can adapt. Aside from packet aggregation, native packet processing within the OTN/WDM systems also allows cost-efficient support for Carrier Ethernet/MEF services. A variety of Ethernet services (E-LINE, E-LAN, E-TREE, and E-ACCESS) can be serviced directly from the converged transport system, including sophisticated traffic management, policing, shaping and classification functions to ensure proper quality of service (QoS). This is particularly of interest to those seeking to offer these services on 100 Gb/s interfaces directly from the transport platforms, as opposed to offering them on a router. Multipoint services such as Ethernet Private LAN (EP-LAN) can also be leveraged to easily mesh core routers together, using whatever port speed makes sense for each router. Rather than creating a mesh of wavelengths to interconnect
The addition of packet-aware transport gives operators a new way to more efficiently utilise their 100 Gb/s router interfaces, making it easier to push fundamental packet processing and transport functions down into this more cost-effective underlay network. The packet-aware optical underlay is somewhat like an express subway system – instead of relying on a taxi or Uber service to route you through congested city streets, the subway can provide individual choices for getting across town predictably and quickly, bypassing all the traffic intersections. By providing packet and traffic management functions directly on OTN/WDM systems, operators can immediately benefit from the ability to map packet flows directly from the router into flexibly sized circuits. Each of these circuits acts as a “virtual” wavelength, and can be switched within the transport network to any other router interface. Packet aggregation from multiple virtual wavelengths converging at a common site can now be done within the optical transport layer instead of within the router layer. In many applications, this natively supported aggregation can reduce the number of router ports required, thereby increasing the efficiency of the entire network. Additionally, with OTN’s ODUflex capability, virtual wavelengths can be flexibly sized. Any sized virtual wavelength between 1.25 Gb/s and 100 b/s (in 1.25 Gb/s increments) can be created to support the packet flows destined for the remote edge router, creating additional
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EP-LAN application.
on different attributes into multiple virtual wavelengths, each of which can provide a differentiated QoS. This gives operators the ability to better control QoS experience for these packets from a transport perspective (e.g. latency, oversubscription, survivability, etc.), even between the same pair of routers. Now, instead of just providing transparent fat pipes between routers, the new packet-aware transport layer can support application- specific bandwidth engineering functions beneath the core router layer. Furthermore, multi-layer SDN control can help simplify and optimise the bandwidth engineering such that traffic is carried at the most optimal network layer, and improving overall network resource utilisation. The emerging capability of packet-aware transport has many network operators excited, since it presents new opportunities for facilitating more efficient core router networks, enabling differentiated bandwidth engineering, and realising high-speed Carrier Ethernet services, all with a keen focus on optimising total network economics.
the routers, operators can instantiate an EP-LAN within the packet-aware transport layer, leveraging multi-layer SDN intelligence, and simply plumb the routers into the EP-LAN through a pair of router interfaces. Finally, transport-layer packet processing can further enhance an operator’s ability to perform bandwidth engineering closer to the fibre infrastructure. With the right hardware and software for inspecting packet flows as they enter the transport system at 100 Gb/s speeds, planners can intelligently map specific packet flows based
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E-TREE
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Packet-aware transport.
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