UK Data Centres


We visited Pulsant’s flag ship Milton Keynes data centre in May 2013. Pulsant is a new player on the market, owned by a well known UK corporation that owns a number of famous high street fashion outlets. Pulsant offer solutions to a diverse range of requirements; from allocating equipment in a stringent Tier 4 environment to low cost budget non critical projects.

We were most impressed with the environment, infrastructure and security. They use cooling corridors, 3 diesel generators and each hall is separately connected directly to 2 different electric power feeds. Driving onto the data centre’s grounds is done through a double gate system and there is ample parking close the main building. Walking in through the main entrance is done through a ‘beam me up Scottie’ type capsule ensuring only one person at a time enters the building. Once in the building access to the various areas is done by a card-based control system.

Apparently a well known high street bank is hosting at Pulsant, the name of the bank wasn’t disclosed to us but we were shown the very impressive highly secure black doors leading into the bank’s private VIP area.


4D Data Centres was founded 1999 by David Barker. In 2007, with angel investment, they purchased what they now consider their flagship facility in Surrey which we visited early in October 2013. 

During office hours customers with prior security clearance can check in with reception. Guests can access the premises by producing ID which is checked and once cleared they are accompanied by a staff member for site tours or meetings. Out-of-hours visitors are verified at the gate by the security guard checking the access list and once on site, there are further security checks via facial and biometric scanning in the air lock doors. There are also anti-tailgating passes which are zoned so that visitors and staff have different access rules, thus preventing unauthorised individuals getting into secure areas or those with confidential material.

4D pride themselves of being one of the greenest data centres in the UK with a PUE of 1.14. All the temperature regulation on the data floor is controlled by the adiabatic cooling system. The clever thing about this cooling system is that it works with the air available in the natural environment, meaning that for up to six months of the year neither cooling nor heating is required. The outside air is simply filtered and pumped into the data floor, so the only power usage is for running the fans which propel the air into the building. Power consumption is kept to a minimum with measures including LED and PIR-activated lighting as well as cold aisle containment achieving 88% reduction in carbon emissions.

The main data floor is approximately 75-80% full. However, the data floor is surprisingly quiet compared to other data centres of its kind. Full racks can be provided power of up to 32 amps.

Cold aisle containment have alarmed doors to prevent cold air from leaking into the main data floor and impeding the efficiency of the cooling system. Each rack within the aisle also has access to humidity and temperature monitors which clients can check via real-time reports. These elements are also closely monitored by 4D and displayed in the main staff area on a large screen.

Fire protection systems include: Morley fire system, VESDA, ionic and optical smoke detectors, beam detectors. Should the VESDA system be triggered, the FM-200 fire suppression system automatically activates. This dispels an inert gas which will fill the data floor and kill the fire.

Each rack, irrespective of size, has combination lock and key lock options. The design of the data floor allows for on-demand cages and suites to be accommodated for the more security-conscious client.

The data centre still has room to grow and they offer quarter, half and full rack options. Large or short-term rack requirements can be accommodated on request.

4D boasts a geographically and physically diverse dark fibre connection and has a mixture of Tier 1 and Tier 2 network connections to the data centre. Clients can put whichever connection they wish into the site or use 4D’s IP transit or connectivity options. 4D also does provide IP transit itself and a selection of connectivity options.

Equipment can be delivered 24/7 and free of charge storage within a secure locked area is available for 30 days. A 24/7 ‘remote hands’ service by on-site technical staff; 15 minutes a day comes as part of all standard colocation packages.

The data centre also offers free wi-fi throughout the building, kitchen with a chill-out area, free loan of toolkits, use of a meeting room for confidential phone conversations/meetings.

4D’s technical team is on-site 24/7 including on Christmas Day. The team is well qualified and relatively large. On the office wall they proudly display all their certificates and qualifications, including accreditations for ethical hacking and Watchguard.



We visited Datum’s first data centre in Farnborough. Backed by a private equity group with over 20 years experience in high-end managed service businesses, Datum opened at the beginning of 2013. As soon as we arrived we noticed the exceptionally high level of security, we were met on the outer perimeter and were driven to the data centre located deep within the fenced area. Datum is IL3 government grade security with tailor made access groups for each client. On the first visit they take biometrics of both index fingers and a facial photo. There is an anti tailgating portal at the entrance with magnetic card and key combination for access. Once through the portal you will step straight onto a sticky matt that would take away any dirt and muck from your feet.

There are three separate buildings, the first one includes reception, offices, meeting room and a hot desking area, the second building includes the data hall, loading bay, un-boxing area and the third building houses 4 generators. 

Datum offer high density computing with up to 30kW per rack as standard and 100% uptime guaranteed. The resilience throughout is a minimum of N+1, some elements are compliant with Tier 4. Adiabatic free air cooling system, 1.25 design PUE, fire detection, fire suppression, the whole place is lights out, all lights are LED. Secured storage areas, supervised loading bay, full remote hands engineering services and clearing of packaging materials. Datum is one level below hospitals on the national emergency priority list for the supply of diesel.  

There are 8 carriers with points of presence on site, four of which are based on their own unique fibre into site; BT, Vodafone, Virgin, Vitesse and Level 3 will be added by January 2014. The A and B infrastructures are coloured orange or blue throughout the data centre as obvious reminders to engineers. 

Every customer has an allocated service manager who provides on a regular basis full detailed reporting of temperature, humidity and power usage. 

The business is aimed at service providers and enterprises and they claim to be cheaper than the major players, a third below Telecity and Equinix.