The Road to the Cloud: High-Speed Autobahn or Country Road?

This guest post was contributed by Jim Morin, Product Line Director, Managed Services & Enterprise for Ciena, and Deputy Commissioner, TechAmerica CLOUD2

Today, storage is literally spilling into the cloud.

Many firms are now providing cloud-based storage services ranging from corporate services like Amazon’s Simple Storage Service (S3) to consumer oriented, easy-to-use cloud storage provided by Dropbox. And let’s not forget Apple’s forthcoming iCloud service, which promises five free GBytes for storing not only music and photos, but also books, videos and even business –oriented information like applications, documents, contacts, calendar and email. Clearly, storage has proven to be an early “killer app” for the cloud, and it’s a market that Taneja Group estimates to be $4B, and will grow to $14B by 2014.

As the industry moves beyond using cloud storage services for less bandwidth-intensive  consumer files like music and photos, to serving the enterprise-class needs of larger, business critical data initiatives,  such as disaster recovery, workload migration and virtualization, the ability to offer a secure, reliable, high-performance connection to the cloud becomes much more critical to success. The reason for this is simple – enterprise cloud customers only have so much time in the day to move their data, and therefore require the right connection and the ability to tune that connection based on their specific needs.

At Amazon Web Services, the company provides a simple chart to determine  how long it will take to transfer data to the Amazon cloud, taking into account the volume of data that needs to be sent and available bandwidth speeds,  assuming standard Internet connections from T1 (1.54 Mbps) though 1 GbE.  When the time to transfer exceeds their recommended threshold value, Amazon suggests physically shipping data on storage devices via its Amazon Web Services Import/Export service.

According to the chart provided, it would take 82 days to transfer 1 TByte of information using a T1 network service, so that means that anything above 100 GBytes should be physically shipped instead of electronically transferred.  (To put this in perspective, 100 GBytes is about the size of a 2004-era, laptop PC disk, so that’s not a lot of information by today’s standards.)  So, this means that a T1 service is not enough bandwidth for many workload transfers.

On the other end of the scale, Amazon estimates that sending 1TByte over a 1 GbE network would take less than one day.  For transfers exceeding 60TBytes over a 1GbE network, Amazon, again, recommends using its import/export service. And so even with a 1GbE network, there are still some serious limitations with cloud data transfer.  (Keep in mind that, multiple-day electronic data transfers dramatically increase the probability of something going wrong – which would extend the job even longer.)

As the cloud business evolves from Software Services running cloud based applications that transfer small amounts of cloud storage, to Infrastructure Services for more mission critical, larger file size requirements, a standard internet connection will no longer suffice. Instead, we need a different network architecture approach. The figures from Amazon drive home the point that Infrastructure as a Service (IaaS) applications like storage, and new applications like Virtual Machine mobility, are going to require more scalable bandwidth to get the work accomplished in a reasonable amount of time. 

Today’s cloud IaaS users are not coping very well with existing network restrictions, which have them sending information via truck instead of electronically. Truck transfers introduce their own security concerns as well as obviously long latency values. Like Amazon, Ciena has calculated that relatively small jobs, such as moving virtual machines and associated storage consisting of .52 TBytes, would take multiple eight-hour days using typical Internet speeds. For larger jobs like a 25 TByte bulk VM migration, it would take multiple days even with a 1GbE network connection. (See diagram below)

To address this need for bandwidth, Ciena envisions a better, high capacity cloud backbone for these next generation cloud IaaS applications. Making this bandwidth “on-demand” makes it more affordable for cloud on-demand use cases like workload mobility, availability and collaboration. For example, a cloud service backbone could scale to a 10 Gbps network and enable more than 30 TBytes to be transferred in a day, easily addressing the bulk VM migration use case, and then scale down once the migration is over.

In addition to more flexible bandwidth, cloud storage services need to address initial concerns of storage security and service reliability, as the physical location of the data is moved to the cloud.  These new storage use cases also drive a higher level requirement for network access, performance and lower network latency.  For example, Amazon assumes 80 percent network utilization for data transfers in their calculations, which we can attribute to typical congestion, retransmission and latency characteristics of shared network connectivity. With Ciena’s proven networking architectures, one can comfortably drive as much as 95 percent network utilization for increased throughput, along with better access performance, scalability, availability and lower network latency.

Today’s private enterprise networks are already prepared to address some of these critical network concerns, but as noted above, this all changes in a cloud model. Amazon’s new Direct Connect service is a response to this need and a forerunner to cloud service providers moving to new cloud networking architectures that respond to the growing amount -- and importance -- of the information in the cloud.  Better network connections will help fulfill the promise of cloud-based enterprise-class infrastructure services.