A Next-generation Enterprise WAN architecture

Courtesy - Network World

 

 

Enterprise WANs have changed very little in the last 15 or so years. While price/bit for the Enterprise WAN has improved somewhat over that time, it hasn’t increased with Moore’s Law as has computing, storage, Internet access, LAN switching … and pretty much everything else associated with IT. And while Internet connections have seen Moore’s Law bring about quantum improvements in price/bit, the unaided public Internet is still not reliable enough to deliver business-class quality of service and performance predictability, which is why the overwhelming majority of Enterprise WANs are based not on IPSec VPNS over the Internet but instead on private MPLS services from telcos like AT&T, Verizon and BT.

Starting now and over the next few years, however, the Enterprise WAN will have a revolution of its own. Closely correlated with the rise of cloud computing, this Next-generation Enterprise WAN (NEW, for short) architecture will help organizations move to cloud computing more quickly, but will be applicable even for those enterprises that don’t plan to use public cloud services for many years, if ever.

This column will cover this NEW architecture: why it will happen, what it will look like, the key technologies enabling it, the implications for various applications, including next-generation applications, the impact on enterprises’ relationships with their service providers, how it enables a smooth migration to leveraging cloud services, and much more.

This Next-generation Enterprise WAN architecture will happen precisely because private WANs need a revolution in price/performance to cost effectively support the next wave of applications and the move on the computing side of the house towards cloud computing. Also driving this trend it the fact that the plain-old-public-Internet is not reliable enough for the corporate WAN today, and that it won’t deliver the necessary reliability or performance predictability by itself that most enterprises demand from their WAN and applications.

One undeniable trend of the last several years has been to favor data center consolidation. This began because of the benefits on the computing and OpEx, rather than the network. Indeed, this trend put even more pressure on the WAN (and on the data center LAN, but that issue is beyond our scope). Server virtualization technology and WAN Optimization technology have further enabled and accelerated the data center consolidation trend. In fact, these are two of the technologies that are key to the NEW architecture.

Three additional technologies also play a critical role. Distributed replicated file service, such as DFS Replication from Microsoft, and similar file synchronization services (e.g. DropBox and Box.net in the public cloud world) have been around for some time, but have come into their own more recently as network bandwidth has become more available and more affordable. One might argue that this is more of a computing/storage/application technology than a network technology; there is some truth to that. Nevertheless, we include it here as one of the key enablers of the next-gen WAN.

Colocation (colo) facilities, and in particular carrier-neutral colo facilities, are our fourth component. While colos have been around for a while, and many IT folks are familiar with them for public-facing websites and perhaps know them as the location for many public cloud services, the nearly infinite amount of diverse, very inexpensive bandwidth available at colos will make them a critical component of this NEW architecture.

Our final technology is the newest one: WAN Virtualization. WAN Virtualization does for the WAN what RAID did for storage, enabling organizations to combine diverse sources of bandwidth and build WANs that have 20 to 100 times the bandwidth, with monthly WAN costs reduced by 40% to 80% or even more, and more reliability and performance predictability than any single-vendor MPLS network. WAN Virtualization is the catalyst of our NEW architecture.

With the combination of these technologies, Enterprise WANs will have far lower monthly telecom costs, far higher bandwidth, and will be more reliable. If that troika alone isn’t enough, this NEW architecture also delivers lower OpEx (people) costs, significantly better application performance and, just as importantly, better application performance predictability. It will enable next-generation applications, e.g. HD videoconferencing.

This architecture also enables benefits and changes beyond those to the WAN itself. It can enable further server consolidation, up to the elimination of all branch-based servers if desired. It will facilitate the centralization of network and IT complexity, e.g. for Internet access and remote site backup.

It will allow enterprises to leverage cloud computing – public, private or hybrid – in an incremental, secure and reliable way. Enterprise WAN managers can prepare and enable their WAN for the move to private or public cloud computing, at whatever pace the computing side of the organizations wants to go, without sacrificing the network reliability and network security they have today.

By doing all of these things it helps lower overall IT CapEx and OpEx, not just networking OpEx. Wide Area Network design is, for the first time in a long time, strategic.

One of the most beautiful points is that most of this next-generation network upgrade pays for itself out of the WAN OpEx budget. It also provides a long-term way to leverage Internet economics and Moore’s Law, giving enterprises a way to cost effectively scale their WANs and leverage new WAN technologies, even those that are consumer-oriented, as they appear. It gives enterprises leverage with their telecom service providers for the first time.

Just as cloud computing is making now an interesting and exciting time to be on the computing side of IT, the confluence of these five technologies - server virtualization, WAN Optimization, distributed/replicated/synchronized file services, colocation and WAN Virtualization – is making this an interesting and exciting time for the Enterprise WAN.