DemoFriday™: Q&A + Video Of Plexxi and CALIENT Demonstrating SDN Driven Optical
SDNCentral’s DemoFriday™ featuring CALIENT Technologies and Plexxi discussed the innovative concept of SDN-driven, dynamic packet-optical datacenter architecture. If you missed it, check out the following Teaser below and then head to the DemoFriday™ video archives to watch the full Video and learn more about how these two companies collaborate to solve some of the most significant problems networks have when trying to scale efficiently to support the needs of large data centers.
If you stopped by for the Answers to Questions from the DemoFriday™ With Plexxi and CALIENT, read on. Care for some visuals? Check Out the VIDEO TEASER below and then head to the Full Demo on our Video Archive page. Thanks!
Questions and Answers from the June 14, 2013, DemoFriday™ with Plexxi and CALIENT Technologies.
Q: How Reliable Is The Hybrid Optical Orchitecture?
A: Plexxi: Typically this architecture is deployed with dual homed rings with redundant power. Optical ring are inherently reliable because of multiple paths, swtiches can be moved, cables cut only affects the directly attached traffic.
A: CALIENT: The 3D-MEMS technology was originally developed for mission critical applications in carrier and government networks where very high capacity links were in play – such as those at subsea cable landing sites. So the technology was always engineered for very high reliability. More recently we’ve been driven by requirements for lights-out datacenters and this has pushed even higher reliability. In reality many architectures would have a number of switches operating in parallel to provide the needed capacity and granularity, so there is a certain amount of redundancy built in to the design.
Q. With The Incremental Fit, What If The CALIENT Path Is Already Used?
A: Plexxi: Only use CALIENT path if there is no path within the Plexxi ring available. So in the event that there is no path available. There are a number of options. The fit algorithm allows you to have different level of changes to the network. At the lowest level, we only add new flows to an existing environment. But there are other levels that will allow us to make room for higher priority flows.
A: CALIENT: Also, you’re not limited to having only a single connection from a Plexxi switch to a CALIENT Photonic switch. Depending on how you want to architect your design there could be several. Some of the original Hybrid network research actually showed multiple Photonic switch connections on each Layer 2 switch.
Q: Can The Architecture Be Extended Beyond A Single Data Center?
A: Plexxi: Yes. As a matter of fact extended for data center applications is ideal. Many times back up and disaster recovery applications use geographically disperse locations. One of the key issues is the cost of the leased line service and connecting that bandwidth to the right place in the data center while minimizing hop count is easily accomplished with the hybrid optical architecture.
A: CALIENT: The Optical circuit switch can be deployed as part of the network within the datacenter – or it can also be setup as part of a reconfigurable add-drop multiplexer node bridging the datacenter and the wide area network – or both. So there is tremendous flexibility in handling traffic within or between datacenters, particularly as these networks converge. The other thing that’s exciting is that SDN applies to both spaces and so as they converge there is a tremendous opportunity to improve performance and lower cost.
Q. How Dynamic (Rapidly) Can The Connections Be Changed Between Plexxi Switches? Between CALIENT Switches?
A: Plexxi: The connections between Plexxi switches can be changed in less than 4 milliseconds. The CALIENT switch can establish connections setup time is typically 25 milliseconds. In a Plexxi/Calient network information for all available network paths are predetermined using algorithms in Plexxi Control during the network fitting process. After the fit is complete all the path information is distributed to all the switches.
Dynamic switch times make sense for path recovery and hardware failures. In a hybrid optical network having rapid switch times is relevant for network failure recovery and also event driven activity where network event thresholds trigger network changes. The Plexxi and Calient connection time frames are more than fast enough for applications in the datacenter. It’s important for operators to consider the underlining applications and networks to determine what are the most appropriate connection times in each case.
We hope you enjoyed this Demo and Q&A transcript. Be sure to catch our upcoming events section and attend more DemoFridays™ to stay current on what the hottest companies are doing in the SDN space.