
We just came back from the Open Networking Summit (ONS ’15). The event was quite interesting, both in terms of the exhibit floor and the talks. There was good participation, albeit more on the vendor side than the customer side.
My main impression is that SDN technologies and solutions are moving from testbeds and concepts to products and early deployments.
I was especially interested in the following keynote talks.
- A talk by John Donovan (AT&T) about the progress they are making in SDN and NFV (click here to watch it)
- A talk by Amin Vahdat (Google) about their datacenter network architecture (click here to watch it)
- And a talk by Jennifer Rexford about an interesting near-term use case for SDN in Internet Exchange Points (click here to watch it).
We were invited by Huawei to demonstrate our collaboration in the Telefonica lab, which also included Ciena, Cisco, and Juniper. Our collaboration was among the five selected in the Service Provider category of the SDN Solutions Showcase and was very well attended. A picture of our booth can be found below. The video that captures this demonstration can be found here.
Our Demo: Multilayer and Multivendor Control over IP/MPLS and Optical Networks
Closer collaboration between the IP/MPLS and Optical layers has been discussed extensively in recent years, but has been slow to materialize due to the lack of central control and multivendor solutions. It is well known that multilayer technology can significantly increase network efficiency, dramatically reduce costs, improve the coordination between the layers during maintenance, restoration, and optimization processes, protect SLAs, and simplify operations. Other parts of our web site go into more details on that.
While some multilayer demos have been shown, even at ONS their underlying architectures lacked key realistic assumptions around system roles and responsibilities that render them unusable for most network operators. I’ll explain more about these considerations in a separate post.
Our showcase demonstrated that multilayer control is real and can be achieved in the near term using existing gear. During the show, we received interesting feedback from network operators about possible uses of our technology to provide business services, such as diverse paths or delay-sensitive connectivity.
The setup of the demo was as follows. Sedona’s multilayer NetFusion platform connected via SDN controllers to an IP network comprising Cisco and Juniper commercial routers, which ran over an optical network with one Huawei domain and one Ciena domain. The entire setup was hosted in a Telefonica lab.
The demo included a novel automatic network discovery scheme that accurately maps the two layers and the cross-layer connections between them. This is shown in the following screenshot in which a crosslink (link across the layers) is selected on the 3D map (in yellow), and the port mapping is shown on the left sidebar. This automatic discovery feature drew a lot of attention.
Once such an accurate view of the network is achieved, it is possible to understand how the IP/MPLS layer maps to the Optical layer; for example, one can select the yellow IP link and see how is mapped to the green optical path as in the following figure.
Next, multilayer optimization can be performed. Action is prompted by a congested IP link and leads to an automatic creation of a new IP link and the best optical path for it instead of the common (but sub-optimal) solution of upgrading the capacity of the congested link itself.
The optimization process decides automatically which link to add after it simulates the expected impact of different options on the IP/MPLS layer; this simulation uses the Cisco IP/MPLS layer online planning function, which is part of Cisco’s WAE (WAN Automation Engine). It also identifies an optical path for the new link that minimizes common failure points with other IP links. The new optical path is selected in consultation with the controllers of the optical domains, considering the vendor-specific constraints of each domain. A new IP link is established and its multidomain optical path is created automatically using the Huawei and Ciena optical SDN controllers. This leads to a prompt easing of the congestion.
Again, the video that captures this demonstration can be found here