The cloud is everywhere today and has become one of the biggest — if not the biggest — topics of conversation in the tech industry. I recently did a CIO roundtable where we discussed the cloud, and the big topics of conversation revolve around security and deployment strategies. This makes sense, based on where we are in the evolution of cloud. However, I do think one of the more important topics related to cloud needs to be the impact on the WAN, and how to optimize user experience. Cloud computing is a network-centric compute paradigm, and the network will play a big role in the success or failure of a cloud deployment. CIOs must shed legacy thinking around the WAN and build a more cloud-ready network.
Traditional networks are built with the tried and true “hub and spoke” design. This is where all branches and remote locations connect to a single “hub” location that delivers network services , including internet access, applications, and other content. With the hub and spoke model, all traffic, in effect, “trombones” where it comes into the central location and then back up one of the spokes to a branch office.
While this “tromboning” is inefficient, it was workable with traditional computing, since the majority of corporate applications are housed in the data center, meaning the only traffic that is “tromboned” is internet traffic. Old-school computing architectures dictated that almost all applications are served up from the data center or the hub. Cloud-based applications, on the other hand, dictate that the applications are pushed out into the Internet — meaning almost all traffic needs to be routed through the central hub location.
So what does this mean for user experience and application performance? With legacy applications, WAN optimization is done with a dual-sided solution built on physical boxes, meaning an actual device is placed in the data center and then one at the branch office. These two boxes then work together to optimize the application traffic between them. With cloud-based applications, network managers have no ability to place a physical appliance in front of the application since it resides in the cloud. WAN optimization, and other WAN services such as security, need to become more cloud-friendly by shifting to virtual appliances.
This actually gives the enterprise higher levels of flexibility with regard to how the WAN is architected. Instead of using the legacy hub and spoke design, branch offices can access the Internet directly, obviating the need to pass through that central hub location. Organizations could implement direct access in larger branch offices where the amount of cloud traffic could overwhelm a WAN link, but then allow small offices to pass through the hub. Alternatively, the company could choose to migrate all locations to direct access and then optimize the connections with virtual services. No hub, regional hubs, and so on — all become valid options. Ultimately, the choice should be made based on business policy or type of application rather than the type of network appliance that is available.
The other area of the WAN that needs to be addressed with cloud is security. There isn’t a study that I have seen or an interview I’ve done where security isn’t the top concern for any IT leader considering cloud. It’s true that security is now being built into cloud services, but it’s also important to secure the network as well. Again, doing this with physical appliances can be difficult if not impossible. Virtual, cloud-friendly appliances are the right solution for the cloud-ready enterprise.
Cloud services are on the verge of exploding, but IT leaders need to ensure they have the right WAN strategies in place before making it the primary application strategy. This starts by shedding conventional wisdom around the WAN and building a network that is more cloud friendly through the use of virtual services.