Beyond the Planning Stage: An SDN Primer
Software-defined networking, infrastructure, and most everything in between is in your sights. It may have been the cost savings that convinced you or perhaps the need to have application-specific routing. Or perhaps you need to expand your network to handle new cloud services or even an expanded data center. But, for whatever reason, you want to make the next step in networking: software-defined networking.
A move to a software-defined network (SDN), whether it's a local area network (LAN) inside the data center or a wide area network (WAN) that goes to the cloud and perhaps encompasses a number of cloud services in a hybrid architecture, doesn't need to be a trauma-inducing event. For one thing, you don't need to change your whole network all at the same time, and for another, setting up an SDN isn't necessarily all that hard. In fact, some vendors feature network management capabilities that are largely self-configuring.
But to get started, you'll need to make some changes in the way you do things. For example, you'll need to acquire switches for your network that don't have a lot of management features, what are usually called "white box" or "white label" switches. But in reality, not all such switches are no-name hardware. Both Dell and HP sell SDN switches that carry their brand labels and are fully supported. Dell's switches advertise support for third-party operating systems (OSes), and the HPE Altoline series supports open networking standards as well. Even HPE's Aruba Networks subsidiary is now making SDN switches, so you have plenty of brand-name infrastructure to choose from no matter what your SDN goals might be.
Selecting the Right SDN Hardware
But as you'll find out, there is also a wide number of switches you've never heard of that handle open networking for SDN, are low in cost, and are just as fast as the products from the names you have heard of. In fact, those Dell and HPE SDN switches are made by the same companies. What's common for most of these is that they are shipped with an open networking OS, such as Cumulus Linux, already installed.
As I mentioned in a previous column, you're going to want to hire an expert to help you select and configure the hardware for your new SDN. While it's possible you could do it yourself, it's almost certainly faster and cheaper to find help.
Managing Your SDN
Once you've moved past the hardware stage, you then need to think about managing the SDN end to end. After all, a major advantage of an SDN is that it's automatically configured according to policies you've set through the management and hypervisor layers. That's where the "software-defined" thing happens.
SDN policies can apply to the entirety of your network or simply to a single piece of virtual infrastructure. They can govern not only when virtual servers are spun up or down depending on traffic or transaction load, but they can also dynamically reconfigure individual virtual instances in response to commands or changing network conditions. That means lots of new flexibility, but potentially lots of complexity, too, so having some idea of your requirements is likely going to be a critical component of your evaluation testing.
As you'd expect, there are a number of management solutions for SDNs. A big player in this area is Aerohive Networks, which makes the management platforms for both local area and wide area SDNs. Other companies, such as Tallac Networks, will help you build your software-defined LAN, and they'll help with consulting and training. Others work with the other part of the equation, the software-defined WAN, where you'll find companies such as Talari Networks.
Saving Money With SDNs
And, of course, you'll find Cisco, networking's long-term big dog, in the SDN arena as well, though in typical Cisco fashion, the company doesn't seem to support open SDN, but rather a proprietary standard of its own. It does support software-defined WANs through its Meraki line of switches and security appliances. Incidentally, it's worth noting that Cisco has a nice tutorial and deployment guide for software-defined networking that's broadly applicable to enterprise users of all sizes.
Cisco also has a handy cost breakdown aimed at illustrating the cost advantage of SDN on the same page as its tutorial. Again, in typical Cisco fashion, the illustration assumes you're ripping out your existing network and replacing it with a SDN. However, if you're not using Cisco and you're not paying for its software-defined WAN management software, then you can change assumptions and get an idea of the cost savings. Even with Cisco's proprietary solution, however, the savings are significant.
Realizing SDN Advantages
If all of this sounds intimidating, then remember the Rash SDN mantra: you don't have to change everything. You can use the SDN you want in conjunction with your existing network and then change pieces or the entire network over to SDN as requirements dictate. Remember, if you're expanding your network, then you're going to have to buy new switches, new management and monitoring software, and new routers, along with all of that other networking gear you'll need, whether the network is physical or virtual.
The advantage of going with a SDN is that it's more flexible, more easily kept up to date, and cheaper than the legacy network you put in last time. Of course, you'll need to get past the learning curve, but with the changes in network management and operations, you'd probably have to do that anyway. There's no question that SDN is the future of networking. The biggest question is whether you and your network are going to be part of it.
This article originally appeared on PCMag.com.