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The era of Software-Defined LAN

(Image credit: Image Credit: Nanantachoke / Shutterstock)

As networks evolve, the race is on to create and define the next generation of network infrastructure, one that enables more flexibility, adaptability, and scalability than ever before, underpinned by extreme efficiency. 

The Software Defined Network (SDN) has been a hot topic for many years, driving the future of networking by shifting the mind set around, planning, implementing, managing, and using networks. Traditionally, SDN has been an approach to using open protocols, such as OpenFlow, to apply globally aware software controls at the edge of a network to access network switches and routers that typically would use closed and proprietary firmware. 

But while flexibility enables adaptability, a faster response to change, enhanced security, simplified fixes, and other improvements, lately SDN can be seen as less of a network-wide technology, and more of a data centre solution. While SDN is a starting point, it’s not the definitive protocol so cannot alone shape which direction networking is heading. 

Therefore the question many analysts are pondering is “how are the benefits of software definition going to be extended to the edge of the network?” Particularly to the intermediate and edges switch and access points (APs) where end-user demand hits the network and everything it connects to.  Advances in networking are best evaluated in terms of improvements not just in the traditional metrics of throughput and capacity, but equally-importantly in terms of operations-staff and end-user productivity. 

Take SD-WANs and SD-LANS for instance. The software-defined WAN (SD-WAN), separates the control and data planes of the WAN, and enables a degree of control across multiple WAN elements (both physical and virtual) not otherwise possible. 

Importantly a portion of the community recognises the need to software-define the WAN in a manner not necessarily identical to the protocols that today define SDN – so they’re related, but different due to essentially different requirements.

The question then is, does SD-LAN – extending software-defined techniques into the access layer of switches, APs, and perhaps even via drivers, eventually into client devices, make sense? 

Benefits of SD-LAN

To understand this, two key elements have to be taken into consideration: What requirements must be placed on an SD-LAN implementation and how softening closer to the edge benefits network managers and end-users - in simpler terms, what are its features, benefits, and advantages? 

Reduced complexity: Network managers around the world are in a constant search to minimise complexity. Simple design is no longer just about end-user products and services, it now extends to the back-end and across the entire network value chain. Application automation, policy, and  simplicity to operations, is exactly what SD-LAN does, resulting in cost savings, improved reliability and much more.   

Reduced costs: Improving productivity is the end goal for many managers today. In order to achieve this, smarter networks with intuitive management tools are required. For instance, an SD-LAN would eradicate the need for expensive LAN controllers by utilising an access point that doubles as a controller, thereby reducing capital expenditure on hardware. 

App visibility: Understanding what role apps play on the network in terms of usage, traffic demands, time-boundedness requirements and more is important. The SD-LAN can use this information in conjunction with policies to fine tune app behaviour automatically, from improving efficiency to prioritising certain apps when necessary to blocking prohibited usage altogether.  

Improved reliability: Any steps which can be taken to further improve reliability must be embraced. SD-LAN implementations are able to proactively deal with reliability issues where possible, as well as security-related emergencies.    

Easy scalability: Managing network growth and adapting to changing demands can be very time consuming, but SD-LAN techniques can mitigate the operational expenditure otherwise required. In a typical scenario, the network will deliver a message alerting the user of the need for an additional access point, and adding that it has already been ordered. The remaining configuration, management, and tuning will be automatic with minimal input necessary.   

Opportunities for MSPs: All of the above applies to managed services providers (MSPs), in other words, SD-LAN will provide real benefits for firms that operate across multiple clients and networks as part of their fundamental business model.  

Network simplicity is an imperative, and SD-LAN clearly benefits from the very simplicity it provisions. 

What’s needed to build an SD-LAN?

Performance followed closely by security which must be comprehensive, efficient and easy to use are the primary requirements for a successful SD-LAN implementation. After all, no other dimension of performance is important if security is in any way compromised.   

An SD-LAN must be able to leverage local authentication mechanisms, which include identity management, and ultimately determine such essentials as authorisation and encryption keys. By doing this, it makes it easier for SD-LAN to respond to security threats with simplified on-boarding and more importantly single-point-of-control system-wide uniformity. 

By basing core implementations as well as policies in software, network shops can realise enhanced configurability, scalability, continuity, and the simplified handling of a wide range of error conditions and the rare but still-challenging outright failure. 

Finally, with respect to cost-effectiveness, SD-LAN must demonstrate that implementations can have a positive impact on costs, particularly with respect to labour-intensive OpEx rapidly outpacing CapEx.   

Over time, the number of conditions requiring the attention of management staff should decline, as automation capabilities learn the ropes. The advent of SD-LAN presents a great opportunity to move to cloud-based management, which offers lower costs (including cloud-based licensing models) and maximum visibility with anytime/anywhere convenience. 

Ultimately, success in SD-LAN depends to a very large degree on the architecture of a given WLAN system solution. Traditionally architecture has been thought of as benefiting the overall performance characteristics of a given installation, but now it’s contributing to advances in capacity, reliability, operations productivity, security, scalability, total cost of ownership, and much more. With the next frontier based on a wireless-first approach, the WLAN industry is set to continue evolving. 

Mathew Edwards, Senior Product Marketing Manager 

Image Credit: Nanantachoke / Shutterstock

Mathew Edwards
Mat is a Product Marketing Manager at Aerohive where he helps drive strategy and vision for Aerohive's wireless LAN solutions.