With a slew of standards updates and regulation changes all your free time could be spent pouring over documentation. In an attempt to shorten the curve and provide information on impact, we have developed a short course that will be published in sections. This first course covers one of the most notable standards that is expected to be published in October 2004 -- TIA's new data center standard TIA/TR 942. This new standard addresses compartmentalization within the data center, the tier and redundancy levels developed by the Uptime Institute. Data centers are divided into the actual data center/computer room where supporting devices reside and where power and telecommunications enter the facilities.
One of the design considerations that caught my attention was the development of hot zones within the data center. In concert with the equipment manufacturers this new design creates hot and cold zones for equipment racks. Understanding that equipment pulls cool air from the front and discharges hot air to the back, new rack placement layouts call for cold aisles (the front of one piece of equipment facing the front of another piece of equipment) and hot aisles where the backs of the equipment share a like aisle. This keeps any one piece of equipment from drawing the heated air of another.
Another key consideration is the call for all horizontal cables to be run in sufficient number to account for growth such that the horizontal cables should not have to be "touched" again after the initial installation. This can be a bit tricky in planning. However with pathways under raised floors, overhead cable trays and cabling within the racks, revisiting these areas has the potential to knock down services for equipment that is running on the existing cable. It is generally less expensive to run all of the cables at once than it is to coordinate moves, adds and changes (MACs) at a later time. The standard recommends a minimum of two outlets at each work area, and of course, these have to be terminated within the equipment distribution areas. Additional cables for devices such as wireless access points, IP video cameras and building automation systems should also be planned and terminated.
The National Fire Protection Association (NFPA) is also involved in data centers standards and authors three standards that impact data center design. The first, and most widely known is the NEC or National Electrical Code. The NEC addresses fire and safety issues. This includes things such as plenum areas, fire, life and safety systems, etc. Two other parts of the NEC that are applicable include NFPA13, NFPA90A. NFPA 13 governs the installation of sprinkler systems and states that if there are combustibles within the plenum space (any space with return air) that not only does the room need to be sprinkled, but the plenum area likewise must be sprinkled. Installation of air conditioning and ventilation systems falls under NFPA 90A.
Dupont has developed a new cable coating that provides far better protection in return air environments and in fact, eliminates the need to sprinkle plenum areas. The cable coating (Teflon® FEP) when applied creates a cabled called a Limited Combustible Cable or LCC. These cables burn slower and create less equipment damaging smoke than CMP cables more commonly known as plenum cable.
There are several Web sites that provide useful information on data centers and are referenced below. These sources will provide information on design, compartmentalized areas, redundancy and resiliency, and links to their events. You can also get a great explanation of the tier levels and types of data centers.
Carrie Higbie, Global Network Applications Market Manager, The Siemon Company
Carrie has been involved in the computing and networking industries for nearly 20 years. She has worked with manufacturing firms, medical institutions, casinos, healthcare providers, cable and wireless providers and a wide variety of other industries in both networking design/implementation, project management and software development for privately held consulting firms and most recently Network and Software Solutions.
Carrie currently works with The Siemon Company where her responsibilities include providing liaison services to electronic manufacturers to assure that there is harmony between the active electronics and existing and future cabling infrastructures. She participates with the IEEE, TIA and various consortiums for standards acceptance and works to further educate the end user community on the importance of a quality infrastructure. Carrie currently holds an RCDD/LAN Specialist from BICSI, MCNE from Novell and several other certifications.