DATA CENTER or CARRIER HOTEL
A data center is where multiple customers locate network servers and interconnect to a variety of telecommunications and other network service providers . Most network access point facilities provide colocation. Carrier hotels and data centers provide the telecom and network industry locations to interconnect with other telecom companies at a physical level, in a neutral facility offering an availability of high density of carriers. As telecommunications continues moving towards packet networks and services, Internet protocol exchanges and interconnection points will be of even greater value to the global telecom community.
Carrier hotels are essentially real estate operations. Carrier hotels make money by leasing or licensing space, uninterruptible power, cooling, and interconnections. The more interconnections and networks present within a property, the more important that property became to the telecom and network provider community. The large networks are demanding compensation from smaller networks and content providers for use of their infrastructure, while the Internet community in general is demanding free access (network neutrality) to that infrastructure used, or contracted from the large facility-based networks. Carrier hotels may also offer additional utilities or options for Tier 2 and Tier 3 networks to interconnect. Carrier hotels are essential to survival of smaller companies hoping to compete with established public utilities such as: AT&T, Verizon, and BellSouth.
BENEFITS
Increasingly, organizations are recognizing the benefits of colocating their mission-critical equipment within a data centre. Colocation is becoming popular because of the time and cost savings a company can realize as result of using shared data centre infrastructure. Significant benefits of scale (large power and mechanical systems) result in large colocation facilities, typically 50,000 to 100,000 square feet). With IT and communications facilities in safe, secure hands, telecommunications, internet, ASP and content providers, as well as enterprises, enjoy less latency and the freedom to focus on their core business.
Additionally, customers reduce their traffic back-haul costs and free up their internal networks for other uses. Moreover, by outsourcing network traffic to a colocation service provider with greater bandwidth capacity, web site access speeds should improve considerably.
Major types of colocation customers:
* Web Commerce companies, who use the facilities for a safe environment and cost-effective, reliable andredundant connections to the Internet
* Major enterprises, who use data centers for disaster avoidance, offsite data backup and business continuity
* Telecommunication companies, who use data centers and carrier hotels to exchange traffic with other telecommunications companies and to access to potential clients
DATA CENTER FEATURES
* Fire protection systems, includes passive and active design elements, as well as implementation of fire prevention programmes in operations. Smoke detectors are usually installed to provide the first warning of a fire developing by detecting particles generated by smoldering components prior to actual flames. This allows for the investigation, interruption of power, and manual fire suppression using hand held fire extinguishers before the fire grows out of control. A sprinkler system is often provided to control a full scale fire. Clean agent fire suppression gaseous systems are often installed to suppress a fire quicker than a sprinkler system. Passive fire protection elements include installation of fire walls around the space, to restrict a fire to a portion of the facility for a limited time.
* Equipment: 19-inch racks for data equipment and servers, 23-inch racks for telecom equipment. Cabinets & cages for physical access control over tenants’ equipment. Private suites are also offered in some data centers. in larger data centers for tenants. Overhead cable rack (tray) and fibreguide, power cables usually on separate rack from data.
* Air conditioning is used to control temperature and humidity in the space. ASHRAE recommends a temperature range of 20–25 °C and humidity range of 40–60% as optimal for electronic equipment conditions. The electrical power used by the electronic equipment is converted to heat, which warms the ambient air in the data centre space. Unless the heat is removed, the temperature will rise, resulting in electronic equipment failure. By controlling the space air temperature, the server equipment is kept within the manufacturer’s specified temperature/humidity range. Air conditioning systems control space humidity by cooling the return space air below the dew point. Too much humidity and water could begin to condense on internal components. In case of a dry atmosphere, additional humidification systems may add water vapor to the space. If the humidity is too low, static electricity discharge may damage components.
* Low-impedance electrical ground.
* Few, if any, windows.
SECURITY
Most colocation centers have high levels of physical security, and are guarded 24/7. CCTV surveillance is normal. Most Data Centers require that customers be escorted by employees. In some data centers, a PIN code or proximity card access system may permit access into the building. Individual cages/cabinets also can have locks. Biometric security measures, such as fingerprint recognition, voice recognition and “weight matching”, are also becoming more commonplace in modern facilities.
POWER
Colocation facilities have diesel generators that start automatically when utility power fails, There may be two or more generators, depending on how the facility is built. The swithchover to generator power is not instantaneous, so colocation facilities have battery backup systems. In many facilities, large inverters to provide AC power from the batteries are provided. Customers may install smaller UPSes in their racks.
DC Power is provided in many facilities with (48V DC) battery banks. DC power generally provides better effeciency.
An alternative to batteries is a motor generator connected to a flywheel and diesel engine.
Data Centers may also provide multiple power feeds into the facility. Customer equipment, and telecommunications equipment often can have two power supplies installed.
INTERNAL CONNECTIVITY
There are different rules in different facilities regarding cross connects between their customers. These rules may allow customers to run cross connects at no charge, or allow customers to order for a monthly cost. They may allow customers to order cross connects to carriers, but not to other customers.
Some colocation centres feature a “meet-me-room” where the different carriers housed in the centre can exchange data.
Most peering points are located in data centers. Because of the high concentration of servers inside larger colocation centres, most carriers will bring in direct connections.
Often there will be a larger Internet Exchange, hosted in the data center, where customers can connect for peering.
EXTERNAL CONNECTIVITY
Colocation facilities usually have multiple points for entry of fiber optic cables into building. This provides redundancy if one bundle of cables is damaged.
INTERNET TIERS
• Tier 1 – the backbone carrier. Tier 1 carriers facility-based, and carry the entire Internet routing table. Internet network providers normally acknowledged as Tier 1s include Verizon (formerly UUNET/MCI Internet), Sprint, AT&T, and Cable & Wireless.
• Tier 2 – regional and 2nd level Internet networks. Also normally facility-based, however still rely on one of the Tier 1s for some routing and transit. This includes cable TV networks, CLECs, and international 2nd tier carriers.
• Tier 3 – Access networks and content service provider networks.
PEERING
is a concept that allows networks to have private mutual agreements allowing the transfer of traffic directly between their networks, without having to use a higher tier network for that transit. Paid peering is how Tier 2 and Tier 1 networks charge smaller networks for accessing their backbones or allowing subscribers to their networks access to the rest of world Internet.
NETWORK NEUTRALITY
assumes users will be able to control the different kinds of content or apps they produce or access, without regard to grade or the quality of service. Thus, whether you pay for a dedicated, unlimited port, or if you pay a usage-based model, what you are paying for is the ability to send and receive packets at an contracted agreed rate with an “upstream” Tier 2 or Tier 1 network provider.
