Time to ramp up to 100G for your DCI solution

– which way should you go?

So, you have decided that it is time to step-up to 100G connectivity in your network. You are not alone. Video streaming, cloud computing and data-replication between sites are just a few of the applications driving the need for more bandwidth in data centers and networks. As a result, enterprises around the globe are on the lookout for efficient, yet financially viable, 100G DCI solutions.

For most corporate data centers, the key concern has, up until now, been managing high-speed connections within the data center itself. In this environment, establishing 100G links is fairly simple with the help of standard pluggable transceivers embedded directly in the switches, routers, and servers.

Enterprises looking to extend the reach to Data Center Interconnect (DCI) solutions, typically spanning the range of 10-80 km (since 90 % of all DCI solutions are within this range), are facing new challenges. What options are available to secure efficient and cost-effective high-speed DCI solutions for these longer distances?

Is DWDM a viable option for enterprise DCI solutions?

For a long time, high-end networks operated by telecom operators and ISPs have been enjoying the benefits of fiber optics and Dense Wavelength Division Multiplexing (DWDM). The beauty of DWDM is that it increases bandwidth by multiplexing wavelengths, allowing different data streams to be sent simultaneously over a single optical fiber network. Up to 96 simultaneous wavelength channels can be connected over one single dark fiber, optimizing the use of the fiber and maximizing network investments.

Corporate data center traffic takes on many different forms: voice, data, and video, running over Fibre Channel as well as Ethernet switches at data rates spanning from 1 up to 100G. If each individual service is to be connected over its own fiber, the number of fibers required equals the number of services required. Bringing the cost of fiber into the calculation, this becomes an expensive way of transporting traffic between sites in a DCI solution.

The benefit of allowing different types of traffic to be multiplexed together, co-sharing a common fiber connection, would make DWDM the obvious alternative for transporting 100G in the DCI scenario. Problem is that while DWDM has become the preferred choice for transporting large amounts of data between sites in telco operator environments, it has traditionally been financially and technically overkill for many enterprise DCI solutions. This is because the high capacity links have been built with high-end solutions designed for the demanding world of telecom operators and service providers with optical reach and network flexibility requirements far beyond the need of most enterprise DCI.

In addition to being highly overpriced for most DCI applications, the building practice of dedicated, chassis based, DWDM solutions typically don’t look anything like the standardized building practices using white box switches and rack-mountable servers in the typical IT-environment.

A new level of standard is needed for high-capacity DCI solutions

To create a viable DCI solution for short to medium distances at a reasonable cost, enterprises are on the lookout for solutions that combine the simplicity and ease-of-use of in-house links with the reach of telco grade DWDM solutions.

In the enterprise datacenter environment, servers play the key role and connectivity is seen as a supporting factor. This means any solution must be compliant with the standard, compact-form factors of data centers, preferably also offering the simplicity of solutions that can be embedded directly in switches and routers, just as the transceiver-based solutions currently used for connections within the datacenter.

The solution should also not require the skills of a qualified telecom engineer to manage, but can be provisioned, monitored and maintained in a similar fashion to other data center equipment.

To conclude, when standardized form factors, easy provisioning and maintenance, minimal foot-print and reduced power consumption are all important decision criteria it becomes clear that large scale chassis based DWDM solution often fits the data center environment as badly as Cinderella’s glass shoe fitted her wicked stepsister. To meet the needs for high-speed connectivity over DWDM in the enterprise environment, at a reasonable cost, a technology break-through and a new level of standard for DCI solutions is needed.