A lot of the focus with Software Defined Networking is on the actual ‘defining’ of the network and how the control plane and data plane are separated to allow dynamic and consistent configuration of network resources. This is rightly so as the ability to manage a network while abstracted from the underlying hardware provides significant benefits that are well documented across many blogs and industry commentaries. An aspect of SDN that is not as prominently commented on is the use of network statistics to improve the decision making of network functions that sit above the switching layer. SDN controllers can be configured to provide access to real-time statistics from managed switches, which in turn can be accessed by other network entities and functions. Many SDN controllers offer a RESTful interface to statistics on any connected switch that can be queried by network entities that normally would not have any visibility on layer 2 or layer 3 stats. For these higher level network entities, which include load balancers, proxies and firewalls, this additional data improves the traffic forwarding decision making process and ultimately improves network performance and resilience.
For example, a load balancer directs traffic to multiple applications via two different switch fabrics (a classic north-south traffic profile). If one of the switch fabrics has a sudden increase in traffic due to a virtual host move event (east-west traffic), the load balancer can make adjustments even though the host replication event may be happening outside its application pool. The adjustment could be to send all traffic via the fully performing switch, ensuring continued performance of the load balanced applications and also releasing resources for the east-west virtual server move.
KEMP Technologies has enhanced the LoadMaster load balancing portfolio with the inclusion of SDN as a load balancing metric. Dubbed SDN Adaptive, this new LoadMaster capability enables better decision making based not just on the status of the destination application but also based on the condition of the underlying switched network paths. This unique capability enables maximum benefit to be extracted from SDN deployments and creating value beyond control and data plane separation.
You can try the KEMP Adaptive Load Balancer App on the new HP SDN Store.