Apr 13, 2017 Regional Network Hubs to the Rescue
Regional network hubs are emerging as a major evolution of the WAN in the age of cloud.
Backhaul or Direct Internet Access…
Many years ago, as SaaS use ramped up, we started tracking whether organizations were backhauling their Internet traffic or allowing branches to go straight to the Internet. (We also were tracking Internet-only branches for some years as well, which is one of the ways we wound up studying SD-WAN early on.)
The reasoning behind our interest was this: MPLS being the dominant WAN technology, and the priciest, were enterprises content to continue backhauling all their Internet traffic to the data center, even as it steadily ramped up in volume and importance? The pass through the DC added performance penalties in terms of latency, and ate up progressively larger chunks of the bandwidth, exacerbating performance problems for both itself and other types of traffic by causing congestion. Direct Internet access generally involved using static routing to direct some or all Internet traffic out over an Internet link at the branch, reducing load on the WAN (saving money and freeing capacity for internal applications) and (in many but not all situations) improving SaaS performance.
This model became increasingly popular among and widespread within organizations, but never really became dominant because of the complexity and fragility of the arrangement. SD-WAN arose in part to make it simple and resilient, and to make it a way of further improving the WAN overall.
…or Regional Network Hubs
Starting last year we started to hear about an a different architecture. Instead of having all or most of the branches in the network going direct to Internet, which still incurs major management overhead when lots of providers are in the mix, it holds onto the idea of hauling Internet traffic to another location first. However, that location is not necessarily a company data center; instead it is likely to be a network services hub only, a location to which other branches connect and from which they gain access to the WAN, to select cloud service providers, and to the wider Internet.
Because they are regional, it can be reasonable to get redundant, high capacity links to them without paying exorbitant rates. Because they are few in number (but more numerous than data centers), it is affordable and manageable to implement a stack of security appliances in them for Internet traffic, and even to set up either direct cloud connects to key cloud service providers, or connections to carrier’s cloud exchanges (often colocated in the same facilities as the hubs).
In some ways, the best part is, using regional hubs doesn’t have to prevent use of SD-WAN: not all locations may have the option of connecting to a regional hub, for example. SD-WAN can strengthen the model by offering alternate means of achieving similar goals, and can take up a role in connecting sites to hubs also.