Wireless in the Data Centre becomes best practice! Mobile computing has made wireless networking essential almost everywhere. Until recently the Data Centre was excluded from this advance but this is now changing with the increasing use of sensors, meters and data centre management software that requires real time updates from users of mobiles, tablets and laptops. This white paper looks at why 802.11 standard wireless networks were previously not installed in data centres and what is changing to make them best practise. Tim Daniels 18 Jul 2014 V3
Contents Executive Summary... 3 1 Why Wireless LAN was unwelcome in the Data Centre... 3 2 Why Wireless is more Secure than Wired... 4 2.1 Enterprise 802.11 Wireless Solutions... 4 2.2 Guest Access... 4 2.3 Mobile Device Management... 5 3 How Wireless Facilitates Best Practise in the Data Centre... 5 3.1 Data Centre Infrastructure Management (DCIM) Software... 5 3.2 Power Monitoring... 6 3.3 Environmental Monitoring... 6 3.4 Asset Tracking... 6 3.5 Personnel Tracking... 7 Summary... 8 References... 9 About AIT... 10 Contact AIT... 10 2
Executive Summary Organisations of all sizes have seen productivity and efficiency gains from an increased use of mobile computing. This has been driving the wider adoption of 802.11 wireless networks everywhere apart from in the Data Centre where the perception of wireless as insecure and unreliable has restricted its implementation. This whitepaper explains why these perceptions are now outdated and looks at how a wireless network makes it easier to implement best practise in the data centre. The benefits that an 802.11 wireless network can bring to a data centre include easier and lower cost deployment of best practise measures such as intelligent PDUs and environmental monitoring sensors, the use of tablets and mobile devices at the rack to update work orders and audit DCIM software in real time and the ability to track assets and personnel. Whilst we don t believe that 802.11 wireless network will replace flood wiring in data centres we believe it has earned its place in best practice data centres. Although the data centre industry remains very conservative, we believe that a major reassessment of wireless in the data centre is imminent as data centre managers become aware of the benefits of installing an 802.11 wireless network. 1 Why Wireless LAN was unwelcome in the Data Centre There have been many objections to the use of wireless in the data centre; the fear that radio waves interfere with servers and storage arrays, security concerns and reliability issues in a difficult environment of metal cages are the most commonly cited. However technological changes have overcome these and forward thinking data centre managers are beginning to implement wireless networks. In the past the fear of interference was a rational response to a perceived risk. The standards for IT equipment in the 1980 s and early 90 s did make computers susceptible to Broadband RF interference. Fortunately in the last 20 years improvements in design, and the development of compliant 802.11 wireless standards, have eliminated this risk. While many devices, as well as faulty electrical distribution and lighting, emit Broadband RF, the level of interference from mobile computing and wireless networks is well within the limits that servers and storage arrays are able to tolerate. Security remains a massive concern for all organisations and no wireless or wired network should be installed without this risk properly assessed and mitigated. A badly designed and badly implemented wireless solution will be as much of a security risk as a badly designed and implemented wired solution. Fortunately the technology is available in many enterprise wireless solutions to ensure that they are at least as secure as your wired network. If required the wireless network can even be contained within the data centre and not integrated to the corporate network and made more secure then your wired network! Similarly it is possible to install a very unreliable wireless network. However if you choose a welldesigned enterprise solution and use a good professional wireless installation company you will get excellent coverage and reliability regardless of your data centre layout. The other big objection used in the past was we don t need wireless we have structured cabling everywhere and lots of switch ports in our data centre and of course in the pre mobile computing 3
world this was right. Today with best practise demanding the use of multiple sensors and meters in every rack and the use of software to collect and make sense of the data, automate work orders and maintain records it makes sense to enable the use of mobile computing and wireless sensors. A professionally installed enterprise wireless network makes it so much easier to achieve the efficiency and productivity gains prescribed by best practise measure. In our view and that of forward thinking early adopters this will make wireless networking in the Data Centre a best practise measure. 2 Why Wireless is more Secure than Wired You have access control to your data centre but you can t stop someone plugging in to a server or switch port. You can however manage your wireless network to stop unauthorised access by using mobile device management and guest access; 2.1 Enterprise 802.11 Wireless Solutions It is important to distinguish between the use of open standards 802.11 wireless solutions as regulated by the IEEE standards committee using 2.4 or 5 GHz and non standards based wireless systems using lower frequencies associated with old industrial systems such as 433MHz. Historically these used a lower frequency to conserve battery life. These non 802.11 compliant systems have gained limited traction in data centres but have been heavily marketed. The advantage of using a lower frequency has largely been eroded by improved battery technology in asset tags and in any case is of no benefit compared to 802.11 systems in powered systems. The use of IEEE approved 802.11 open systems that connect to any Wi-Fi enabled device produced by any vendor ensures that costs are kept down and prevents data centre mangers being locked in to a specific brand of sensor or asset tag. It also ensures that enterprise class security and reliability is possible through integration with existing IT systems. While some data centre managers may prefer to not depend on their IT department and install a closed system that can t integrate with other devices this severely limits the benefits of installing a wireless solution. In such cases it is perfectly possible to install an 802.11 compliant system and not integrate it with the corporate network. This provides the data centre manager with his own closed network but still allows him to connect to any mobile device and benefit from the security and reliability of an 802.11 solution. 2.2 Guest Access Guest Access control is included in all enterprise wireless solutions. This means that visitors and customers can bring in their own mobile devices and use them in the data centre to connect to the Internet without getting access to your network. This is achieved by a walled off guest network that cannot access the your corporate or maintenance networks. You can set up multiple guest profiles for different categories of visitors such as customers or temporary employees, with different access policies for each. Some guests may be granted access only to the Internet while others can be given restricted access to certain parts of the network such as the customer s racks. Even more granular control can be exerted; modern Enterprise vendors include stateful firewall capabilities and even the ability to recognise traffic by application, with deep packet inspection. A data centre 4
manager may decide to limit access to social media apps such as Facebook or Twitter or potentially nefarious applications like Bittorrent that might port hop to get round restrictions placed by less powerful firewalls. The best WLAN solutions integrate with existing authentication systems so that you can control not only what a guest can access but the location from where they can gain access and how long and with how much bandwidth they can use. 2.3 Mobile Device Management Mobile Device Management (MDM) software allows you to take some or full control of devices that you trust to give access to your corporate network. It can remotely wipe authorised devices if they are lost or stolen and allows you to control what authorised users can see and do from their mobile devices with different policies set according to location. Administrators can push productive apps through a corporate dedicated app repository. Content can be securely accessed with less data loss, enabling far greater levels of productivity from the devices that staff already have in their pockets. 3 How Wireless Facilitates Best Practise in the Data Centre The following applications are either enabled or enhanced by the use of wireless, which will make Wi-Fi ubiquitous in the data centre; 3.1 Data Centre Infrastructure Management (DCIM) Software Most data centre managers will use DCIM software either in the form of real time monitoring or a more comprehensive solution such as Emerson s Trellis, Nlyte, Raritan s dctrack or AIT s PIM s to help them manage their environment. Some of these will also make use of tablets, laptops and other mobile devices to directly update the software in real time. This can include capturing the bar codes of new IT equipment and updating records of moves and changes as they go to ensure that the database is up to date and their model reflects reality. This ensures asset and capacity management is accurate and that all connections are mapped to help support teams diagnose, find and fix faults quickly. Locating assets and cabling on an Android 5
3.2 Power Monitoring Some Intelligent Rack PDUs are now available with wireless as well as wired Ethernet interfaces. By connecting PDUs to a wireless network you reduce switch port costs and eliminate additional cabling requirements. This can be useful in data centres where switch ports are limited and makes it easier to deploy intelligent PDUs. It also eliminates the need for additional hardware that some intelligent PDU systems use to reduce the number of switch ports used. 3.3 Environmental Monitoring Wireless temperature and humidity sensors are also widely available. Like wireless intelligent PDUs these are easier to deploy and move, and don t require additional cabling or switch ports. Best practise is to Wi-Fi Dongle fit temperature sensors at the top, middle and bottom of each rack on the inlet side of the server, along with a humidity sensor. However because of the restriction on switch ports and cabling this is rarely achieved and in most data centres only a few worst case hot spots are monitored. Installing an 802.11 compliant enterprise wireless network makes the deployment of best practise monitoring cheaper and easier to achieve. 3.4 Asset Tracking Wireless networks are widely used for asset tracking in other industries where the location of an asset can be determined to within 1 or 2 metres. This may be accurate enough for some data centre assets but may not be enough to track assets to within a specific rack. The actual accuracy is dependent on the number of wireless access points installed. Accurate asset tracking requires an overlap of 3 or more access points to triangulate and fix the location. Rack specific location tracking, solutions such as Raritan s Asset Management Tags, can provide an accurate location down to U level in the rack. Such solutions rely on hard-wired tags connected Typical Asset Wi-Fi Tag to a vertical strip within the rack. If the handcuff link is broken then the system immediately warns that the asset has been moved. If the link is broken and then reconnected in another U location or rack you instantly know it has been moved and have an accurate location. Wireless real time location systems (RTLS) rely on asset tags with batteries that last about 5 years. The benefit of wireless asset tags is that they are much more flexible than hard-wired tags and continue to provide location information even after they are disconnected. So if a server is moved across the data centre you know its location, to within a couple of racks, and can quickly scan the barcodes of the servers around that area to find the server you are looking for. Given that location signals continue to be emitted even if the asset is moved and disconnected (or even hidden in the cleaning cupboard!), it is a surprisingly practical solution. 6
3.5 Personnel Tracking Personnel asset tags can be worn by staff and visitors to provide a log of all their movements. This can be used to ensure contractors do not go into certain areas, and even provide an instant warning if they do. Personnel tags may also be used in lone worker or man down scenarios where people have to work alone, perhaps during a night shift. Some types of tags are fitted with an alarm button that can alert others if they get into trouble. Other variants include displays that can receive text massages, provide an audible alert sound and flash LEDs on the tag. The alert provides the exact location of the badge. The systems Wearable Wi-Fi Badge can be programmed to re-point video cameras, control door locks and lighting, and call appropriate local assistance. Personnel badges are about the size of a credit card and use rechargeable batteries that may be quickly re-charged when not in use. 7
Summary Enterprise 802.11 wireless network solutions have come a long way in the last two decades. Wireless connectivity has become ubiquitous, driven by the growth of mobile computing and the benefits in productivity it produces. The technical objections to using wireless in the data centre have been overcome by an improvement in IT standards making servers and storage arrays resistant to Broadband RF interference and by the huge advances in security and reliability in enterprise wireless solutions. The levels of security and control that a data centre manager can exert over a wireless network now exceeds that of the wired network. A wireless network makes it easier and cheaper to deploy best practise measures such as sensors, intelligent PDUs and asset tracking in the Data Centre. It will also help you make the most of your investment in DCIM software, like AIT PIMs, by enabling the use of Android and Apple tablets to update moves and changes in real-time keeping your asset, capacity and cable connection model synchronised with reality. The benefits of wireless connectivity in the data centre include; Easy, low cost deployment of best practise measures such as intelligent PDUs and environmental monitoring sensors Use of tablets and mobile devices at the rack to update work orders and audit DCIM software in real time Guest Access providing controlled access to customers, contractors and temporary staff Asset tracking locating valuable equipment down to 1 or 2 metres Personnel tracking Locating staff, tracking contractors and guests, as well as providing man down alerting Now that the real objections have been overcome we believe that these clear benefits will make it part of best practise to install enterprise 802.11 standard wireless networks in the data centre. While the data centre industry remains very conservative the pace of adoption will increase as more data centre managers become aware of the efficiency gains and control that is achievable with a wireless network. 8
References 1. AIT Secure Network Solutions http://www.ait-pg.co.uk/secure-wired-and-wireless-network-solutions/ 2. AIT Data Physical Infrastructure Management Software (PIMs) http://www.ait-pg.co.uk/data-centre-management/data-centre-infrastructuremanagement-dcim/ait-physical-infrastructure-management-software-pims/ 3. Bring Your Own Device http://www.ait-pg.co.uk/secure-wired-and-wireless-network-solutions/bring-your-owndevice/ 4. Mobile Device Management http://www.ait-pg.co.uk/secure-wired-and-wireless-network-solutions/bring-your-owndevice/mobile-device-management/ 5. Guest Access http://www.ait-pg.co.uk/secure-wired-and-wireless-network-solutions/wireless-lan/wlanguest-access/ 6. Wi-Fi based Asset/Personnel Tracking http://www.ekahau.com/real-time-location-system/technology/how-rtls-works 9
About AIT AIT Partnership Group provides data centre management solutions to business and the public sector. Customers include British Airways, Sentrum Colo and the BBC. AIT also supplies and supports secure network solutions across the UK including wireless networks, MBM/BYOD, Firewalls and point-topoint microwave solutions. Contact AIT http://www.ait-pg.co.uk T: 0845 017 70017 W: Contact Form 10