Whether the requirement is internet connectivity for cloud-based applications or links to a private WAN, most organisations now recognise the importance of a carrier-neutral data centre. However, while the list of possible connections available may look compelling – some data centres boast hundreds of carriers – it is important to look beyond the top-line promises.
Fibre Provider
When it comes to data centre connectivity organisations have diverse requirements, from cost to Quality of Service, and choice is key. But what does that choice actually mean? Telcos routinely route traffic over each other’s physical networks – indeed, often just reselling each other’s services. So if a company opts for a connection from a given provider, the chances are that the traffic is routed over networks belonging to a variety of other telcos.
This is a great model for creating competition and offering choice, with Tier-2 providers aggregating services from different Tier-1 providers to offer different Service Level Agreements (SLA) and cost models. However, it is not so good for resilience – especially if a company opts for primary and secondary connections from different carriers that are actually routed over the same physical infrastructure from a Tier-1 provider such as BT or Level 3. If anything happens to damage that physical cable both connections will fail.
Before making the data centre decision, therefore, it is essential to ask some pertinent questions, from the number of different entry points into the building to the number of Tier-1 and Tier-2 carriers that are providing connections within that data centre.
Digging Deeper
So what are the questions you need to ask?
1. The first question is whether the data centre has a relationship with its incumbent WAN provider. If so, it will be easy to connect into the network and get operational quickly. If not, there will be a number of challenges facing in creating a link to the data centre that could add significantly to the cost.
2. How many diverse entry points are there into the data centre building? Don’t just assume that because a data centre provider boasts hundreds of carrier relationships that there are many different physical connection points: indeed, many data centres have just two. As a result, choice is limited and the carriers will be constrained in the SLAs they can offer simply due to infrastructure limitations.
3. How many Tier-1 providers & how many Tier-2 providers are there – and which is the underpinning carrier network being used by each?
a. To ensure resilience an organisation needs to use different infrastructure coming into the building at different entry points.
b. To ensure choice a data centre should have not only multiple entry points but also lots of Tier-2 carrier relationships – this will enable both competition and the creation of different cost/quality of service packages to meet diverse business requirements.
4. How much will it cost to get a connection from your office location to the data centre? For example, to get a 10Gb connection from a central London office to an office outside the M25 will cost significantly more than connecting to a central London data centre.
5. What are the connectivity options outside the UK – to Europe, the US or Asia-Pacific? Depending on present and future business requirements, access to a carrier with excellent international connectivity capacity could be important.
Planning Ahead
While organisations typically only review the WAN provider every 3-5 years, it is important to remember that the data centre relationship is likely to last longer. What happens in three years’ time if the company decides to change carrier for the WAN and the new provider does not have a relationship with the data centre?
While it will be possible for the new carrier to connect to an existing service within the data centre, the process will not be straightforward and the company is likely to incur additional costs – costs that may undermine the business case associated with the carrier decision. Ensuring the data centre has a broad range of Tier-1 and Tier-2 providers on board is key to avoiding either additional costs or constraining carrier options further down the line.
Indeed, during the typical life of a data centre relationship an organisation’s connectivity requirements will evolve. Hoping that a data centre will add carrier relationships during this time may be a little risky – especially when it comes to those critical Tier-1 relationships that add resilience.
The truth is that once a data centre is in place, adding new physical connections is far from easy. So if a data centre today only offers two physical connections, it is likely that is all it will ever offer. That may be fine – it will still enable Tier-2 carriers to offer a variety of services across the infrastructure – but it does limit a company’s options in the longer term.
From resiliency to cost, choice to quality of service, accurately ascertaining the true quality of the carrier relationships on offer with a data centre today should be an essential component of any decision-making process.
