It’s all very well saying we need fibre, but that’s only the transport medium. What are you connecting to? In this blog, Richard Auld of Concept Solutions People describes how our business connectivity is changing and why the internet is no longer the best way to connect to your cloud, private or public.
In the dim and somewhat distant past, fibre connectivity meant a private network and a choice of proprietary signalling systems. Frame Relay, X.25, ATM etc. were all proprietary and solved data transmission problems in different ways, but all were for big business only, due to their costs.
The invention of the World Wide Web by Tim Berners-Lee offered a means of connecting to anyone’s server, world-wide, with a single click and so our addiction to hosted services began.
The World Wide Web is a ubiquitous and easily used network meaning that we can communicate with a wide range of applications without having to worry about how we connect. We just type a URL and the World Wide Web finds out where it is and connects us to it. We don’t need to know IP addresses, because the URL and DNS do all that for us.
Like all great inventions, it just worked, and the cloud has become the place where we access applications and store data. The cloud is not a place, just a description of data held in multiple data centres, all connected via high bandwidth networks to global Internet Service Providers.
So, the servers we connect to are now mostly in data centres – whether in a private data rack or cabinet rented by your own company, or one being run by a cloud service provider. We use apps and storage that rely on internet connectivity to someone’s data centre.
However, the internet is no longer your best, or only, option to connect your business to the applications and services you use because file sizes are getting bigger (Terabytes of data are not unusual) and applications that are hosted may demand low latency to work at their best.
What’s wrong with the internet as my only network?
Firstly, we need to send and receive more and more data. If your servers are now in a data centre every file you access and change has to go backwards and forwards. The internet is OK for small files but bigger file sizes start to cause problems. Upping your internet bandwidth is not the answer, because data throughput is not the same as bandwidth.
Secondly, more applications demand low and consistently latency to give a good user experience and the internet is about getting information through, not keeping latency consistent. Your VPN or IPSEC service may struggle.
1. Throughput is not bandwidth.
You may have a 1Gbps Internet connection in your office and the same in your data centre (or your cloud provider will have 10Gbps or even 100Gbps ports) but you will never get anything close to a sustained 1Gbps throughput when transferring data over the internet. This is for 2 reasons:
- The internet is a massive shared resource and while your quality business ISP will have an uncongested network, they only control it as far as their handoff to their Tier 1 Global IP Transit provider. Once your data is consigned to the Internet it is at the mercy of the weakest link and most congested router.
- Even if the route to your cloud is uncongested, the technicalities of TCP/IP networking, forward error correction and latency slow your data to a sustainable rate much lower than your maximum bandwidth.
Together these mean that your 1Gbps peak rate might drop to less than 100Mbps sustained while attempting to upload a large file to your cloud provider for processing or storage. This is OK for general business documents, but for a “big data” file of several Terabytes, this is unacceptably slow.
2. Latency is not low or fixed.
The great thing about the internet is that it will always try to find a way to connect. Unfortunately for latency, this means that routes change, and the latency also varies, sometimes randomly. If you have a latency sensitive application, this means that it won’t know what is going on and it may fail, time out or give a poor user experience.
So, how do we overcome these issues?
Dedicated “dark” fibre connections offer the best way to connect your offices to the data centre where your private, public or hybrid cloud is located.
A dedicated fibre connection is a point-to-point link consisting of a pair of optical fibres that is dedicated to you and not a circuit over a carrier’s network. It’s exactly the same as a fibre cable inside your building, except that it can stretch over tens or even hundreds of kilometers. These are sometimes called dark fibre, because you light the fibre with your equipment and choose the services you want to enable.
The diagram below shows how we currently connect using Internet Access from our ISP and how we will connect in future using dedicated fibre.
If your business doesn’t have its own rack in the data centre, your ISP will have one to terminate the dedicated fibre link and provide you with access to the other services. If they can’t offer you a dedicated fibre link, don’t worry, we can.
Dedicated fibre links benefit from:
It’s a point-to-point link with only your equipment at each end so you can run Ethernet protocol and treat it as a LAN extension.
Low and fixed latency.
The route is direct between two points. It’s not as the crow flies but it’s probably as close as you can get. So, the latency is just the fibre distance and the speed of light in glass. The route can’t change so the latency is fixed, not variable.
Rather than having a fraction of a carrier’s fibre, you rent the whole fibre, so you can choose to use it for 1Gbps, 10Gbps, 100Gbps or you can multiplex the fibre using Dense Wave Division Multiplexing (DWDM) to create 32 or more wavelengths per fibre pair. Even if you don’t need all of this today, your fibre link is future-proofed. You will never need to order another circuit into your offices, just increase bandwidth on your dedicated fibre and connect via the data centre.
Once the fibre is connected, you are in control. If you want more bandwidth, add a wavelength by simply plugging in another patch lead from the DWDM equipment to your router. Select your bandwidth – 1Gbps, 10Gbps, 100Gbps – by choosing an appropriate interface to your router. The “path” is there and ready to use, you don’t need to call your carrier and wait weeks while they go through their tedious processes. Using DWDM you can also use Ethernet or other protocols such as Fibre Channel to suit your own needs.
With file sizes increasing and applications demanding low and stable latency, the future lies in a dedicated fibre link between your business premises and a local data centre. This is your gateway to Cloud Service Providers, private cloud, storage and direct peering with industry partners and software providers. Recent developments in fibre deployment and pricing mean that it is now much more cost-effective to utilise a dedicated fibre than ever before.
In the next instalment we will look at some typical costs and applications of dedicated fibre infrastructure.