Datacenters look to SDN for the next chapter of interconnection

August 18 2020
by Craig Matsumoto


Having seen enterprise IT distribute outward to public and private clouds and SaaS, some multi-tenant datacenters (MTDCs) are putting a stronger emphasis on interconnection. The pitch to enterprises is that a colocation deployment, combined with interconnection, can become a hub for all of this cloud/SaaS activity – and to make this hub more cloudlike, operators can go a step further with software-programmable interconnection (SPI).

SPI involves infusing datacenter interconnection with software-defined networking (SDN) or similar technology that can automate the provisioning of connectivity. The result is that cross-connecting becomes fluid, with wait times measured in minutes rather than days or weeks. Ideally, this connectivity also becomes self-service, with the customer creating virtual cross-connects on their own.

The 451 Take

The significance of SPI goes beyond the benefits to the interconnection service. SPI can create a fabric that connects many datacenters across regions and continents and makes them feel, to the end user, like one giant datacenter – all endpoints are equally easy to access, at least in theory. This kind of SDN-driven connectivity is already being used by some datacenters and service providers to create direct, private connections into the public clouds, and it could play a role in future edge computing as well. The key is the behind-the-scenes automation that renders the cross-connecting process invisible. The big-picture effect, some datacenter operators hope, is that SPI will help make their services more relevant to enterprises that had not previously considered colocation.


Enterprise IT is being pushed outward to clouds and SaaS providers, and this new enterprise model needs a new type of network. It can certainly be based on the public internet, but for some enterprises, the mission-critical nature of their cloud- and SaaS-based work justifies deploying something more reliable, predictable and secure. This is where datacenter interconnection can come in, offering private connectivity.

In place of the WAN that connected employees to IT services, enterprises could have an interconnected wide-area fabric reaching out from a colocation facility to services hosted in disparate locations, potentially around the globe. Just as AWS Direct Connect and Azure ExpressRoute represent connectivity alternatives to the public cloud, an MTDC armed with SPI could extend that idea to include connectivity to the panoply of services that enterprises now rely on.

As 451 Research describes in a recent report, SPI is setting the bar for the datacenter interconnection services of the future. Not all datacenters will adopt SPI, but the speed and automation it provides will become table stakes for the leading operators.

Some of the report's key findings include:

  • Interconnection is becoming a self-service endeavor via web portals. APIs and-user experience will start to become bigger parts of the datacenter lexicon.

  • Enterprise business continues as an important growth opportunity for many MTDCs, but enterprises are growing accustomed to the agility and automation found in the cloud. SPI brings that agility to interconnection.

  • Enterprises are increasingly dependent on connectivity to third parties, including public clouds, SaaS providers, and partners' applications and data. What used to be the 'enterprise network' has become a web of outward connectivity. With SPI, a datacenter operator can offer to harness this connectivity and move it to secure private connections while handing control over to the customer.

  • SPI's competition includes vanilla internet connectivity, VPNs, SD-WAN and network-as-a-service vendors that offer entire enterprise backbones. Datacenter operators could strike partnerships to offer the latter two options.

  • SPI fits into what 451 Research calls invisible infrastructure – infrastructure that 'just works' without the user knowing or caring about the underlying details. In the networking realm, this trend points toward SDN becoming commonplace, with networking becoming effortless and automated from the user's point of view. (It is not surprising that some early SPI efforts are controlled by customers via self-service web portals.)

    If we extrapolate on this idea, we can anticipate that networks will eventually request connectivity from one another without human intervention, and applications will use APIs to 'talk' to the network and establish connectivity on their own. Long before that degree of fluidity arrives, however, some customers will have stopped tolerating delays of weeks or even hours to set up cross-connects. As customer expectations drift toward invisible infrastructure, SPI could become more important. As discussed in the report, some of the datacenter providers offering SPI to varying degrees include Cologix, CoreSite, Cyxtera, Digital Realty, Equinix, Flexential, Interxion (now owned by Digital Realty), NTT Communications and QTS Realty Trust.

    Connectivity partners

    Not all datacenter operators have the skills and tools to convert to SPI, but the good news is that they don't have to go it alone. An ecosystem of connectivity providers (often referred to as aggregators or brokers) can deliver SPI for MTDC providers uninterested in developing the technology. One example of this is Digital Realty's Service Exchange, which is powered by Megaport. For the operators that do run their own SPI fabrics, such as Equinix, connectivity platforms can extend the network to reach more customers and locations. Other examples of these connectivity suppliers include Epsilon, PacketFabric and PCCW Console Connect.


    Some early adopter enterprises, generally larger ones, have adopted this combination of colocation and interconnection. MTDCs would like to see the broader enterprise market join them, but one obstacle is the fact that many enterprises do not view colocation this ambitiously. Only 30% use colocation at all, according 451 Research's Datacenters 2019 survey. The same survey found that the number one use of colocation is not interconnection, but disaster recovery, chosen by 53% of enterprises.

    While these enterprises could be using colocation for other purposes as well, the disaster recovery data point suggests that many of them enlist colocation tactically to address individual problems. Datacenter operators vying to offer interconnection platforms must convince enterprises to think of colocation through a strategic lens instead. After all, connectivity has value: 72% of respondents desire interconnection from their colocation provider, and 59% believe it's important for colocation to include direct connectivity to the public cloud (see figure below).

    Figure 1
    Important Services for a Colocation Provider to Offer
    451 Research, Datacenters, Annual Survey 2019