Data center of facebook

Data center of facebook

     The milestone is a result of Facebook's two-year-old Open Compute Project, in which the company created its own specifications for servers and shared them with the world for anyone to use.Instead of buying servers directly from the likes of HP and Dell, Facebook creates more efficient designs that strip out extraneous hardware and software and then pays original design manufacturers to build them.As we reported in February , the data center in Sweden was set to become Facebook's first containing only Open Compute servers.

     "As our systems come online for the first time, we are proud to say that this is likely to be one of the most efficient and sustainable data centers in the world," Facebook wrote in its announcement, stating that the data center is now handling live traffic from users around the world."All the equipment inside is powered by locally generated hydro-electric energy. Not only is it 100 percent renewable, but the supply is also so reliable that we have been able to reduce the number of backup generators required at the site by more than 70 percent. In addition to harnessing the power of water, we are using the chilly Nordic air to cool the thousands of servers that store your photos, videos, comments, and Likes. Any excess heat that is produced is used to keep our office warm."

       "Nearly all the technology in the facility, from the servers to the power distribution systems, is based on Open Compute Project designs," Facebook continued."This Facebook-founded initiative encourages the development of 'vanity-free' hardware designs that are highly efficient and leave out unnecessary bits of metal and plastic."

       The data center has an impressive PUE rating (power usage effectiveness) of 1.07.This means the building consumes 1.07 watts of power for each watt needed by computing equipment.Facebook has been posting near-real-time PUE data for its US data centers and plans to do the same for the Sweden

       In addition to server designs, the Open Compute Project has created and released designs for server racks, storage systems, motherboards, and interconnects.Last month, Facebook announced that its next goal is to release a design for a top-of-rack switch that can run any type of networking software .This could help give businesses alternatives to Cisco and the other leading network vendors.

Inside the headquarters of Facebook.

A number of Facebook employees came from different countries. To mobilize to help translate the site for over 70 languages​​.

     

References: http://arstechnica.com/information-technology/2013/06/facebook-opens-data-center-filled-entirely-with-servers-it-designed/

Data center of Google

Data center of Google

Efficiency

     Our data centers use 50% less energy than the typical data center.We raise the temperature to 80°F, use outside air for cooling, and build custom servers.

Inside data centers

Environmental, health, and safety

Certifying our high standards:

Google is the first major internet services company to gain external certification of our high environmental and workplace safety standards throughout our US and European data centers. More specifically, all of our US and European data centers have received voluntary ISO 14001 and OHSAS 18001 certifications. Additionally, we’re the first company in the United States to obtain multi-site ISO 50001 Energy Management System certification, covering 6 US data centers.

Our environmental, health, and safety policy:

Google owned and operated data centers will lead the industry in environmental protection, pollution prevention, health, and safety. We will take a proactive approach in our activities and aim to continually improve data center environmental, health, and safety (EHS) performance. We will comply with applicable EHS legal requirements, and as appropriate for other EHS matters, we will implement voluntary standards or best management practices.

Data center locations

     We own and operate data centers around the world to keep our products running 24 hours a day, 7 days a week. Find out more about our data center locations, community involvement, and job opportunities in our locations around the world.

Americas

• Berkeley County, South Carolina
• Council Bluffs, Iowa
• Douglas County, Georgia
• Quilicura, Chile

• Mayes County, Oklahoma
• Lenoir, North Carolina
• The Dalles, Oregon

Asia

• Hong Kong
• Singapore
• Taiwan

Europe

• Hamina, Finland
• St Ghislain, Belgium
• Dublin, Ireland

References : http://www.google.com/about/datacenters/

Computer Network

Computer Network

     A computer network (or data network) is a telecommunications network that allows computers to exchange data.The physical connection between networked computing devices is established using either cable media or wireless media. The best-known computer network is the Internet.

Network devices that originate, route and terminate the data are called network nodes.Nodes can include hosts such as servers and personal computers , as well as networking hardware.Two devices are said to be networked when a process in one device is able to exchange information with a process in another device.

Computer networks support applications such as access to the World Wide Web , shared use of application and storage servers , printers , and fax machines, and use of email and instant messaging applications.The remainder of this article discusses local area network technologies and classifies them according to the following characteristics: the physical media used to transmit signals, the communications protocols used to organize network traffic, along with the network's size, its topology and its organizational intent.

Type of computer network

Local area network

     A local area network (LAN) is a network that connects computers and devices in a limited geographical area such as a home, school, office building, or closely positioned group of buildings.Each computer or device on the network is a node.Wired LANs are most likely based on Ethernet technology.Newer standards such as ITU-T G.hn also provide a way to create a wired LAN using existing wiring, such as coaxial cables, telephone lines, and power lines.

Metropolitan area network

     Metropolitan area network (MAN) is a large computer network that usually spans a city or a large campus.

Wide area network

     A wide area network (WAN) is a computer network that covers a large geographic area such as a city, country, or spans even intercontinental distances.A WAN uses a communications channel that combines many types of media such as telephone lines, cables, and air waves.WAN often makes use of transmission facilities provided by common carriers, such as telephone companies.WAN technologies generally function at the lower three layers of the OSI reference model : the physical layer , the data link layer , and the network layer .

Network topology

  

      Network topology is the layout or organizational hierarchy of interconnected nodes of a computer network.

Common layout are:

•  A bus network : all nodes are connected to a common medium along this medium.This was the layout used in the original Ethernet , called 10BASE5 and 10BASE2 .
• A star network : all nodes are connected to a special central node.This is the typical layout found in a Wireless LAN , where each wireless client connects to the central Wireless access point .
• A ring network : each node is connected to its left and right neighbour node, such that all nodes are connected and that each node can reach each other node by traversing nodes left- or rightwards.The Fiber Distributed Data Interface (FDDI) made use of such a topology.
• Mesh network: each node is connected to an arbitrary number of neighbours in such a way that there is at least one traversal from any node to any other.

Devices

• Modem
• Network interface card
• Wireless access point
• Rcpeater
• Hup
• Bridge
• Switches
• Router
• Gateway

The advantages of computer networks.

• Ease of communication.
• Hardware together.
• Software together.
• Use of data and information sharing.

Home Network

Home Network

       A home network or home area network ( HAN ) is a residential local area network (LAN) for communication between digital devices typically deployed in the home, usually a small number of personal computers and accessories, such as printers and mobile computing devices.An important function is the sharing of Internet access , often a broadband service provisioned by fiber-to-the-home or via Cable Internet access , Digital Subscriber Line (DSL) or mobile broadband by Internet service providers (ISPs).If an ISP only provides one IP address, a router including network address translation (NAT), proxy server software and typically a network firewall , allows several computers to share the external IP address.The router function may be assumed by a PC with several network interfaces, but a dedicated router device is more common, often including a wireless accesspoint , providing WiFi access.

   Home network

       A home group is a feature that allows shared disk access, shared printer access and shared scanner access among all computers and users (typically all family members) in a home, in a similar fashion as in a small office workgroup, e.g., by means of distributed peer-to-peer networking (without a central server). Additionally, a home server may be added for increased functionality.

        A Windows HomeGroup is a new feature in Microsoft Windows 7 that simplifies file sharing. All users (typically all family members), except guest accounts, may access any shared library on any computer that is connected to the home group. Passwords are not required from the family members during logon. Instead, secure file sharing is possible by means of a temporary password that is used when adding a computer to the HomeGroup.

Physical transmission media

         Wireless radio one of the most common ways of creating a home network is by using wireless radio signal technology; the 802.11 network as certified by the IEEE. Most products that are wireless-capable operate at a frequency of 2.4 GHz under 802.11b and 802.11g or 5 GHz under 802.11a.Some home networking devices operate in both radio-band signals and fall within the standard 802.11n.A wireless network can be used for communication between many electronic devices, to connect to the Internet or to wired networks that use Ethernet technology. Wi-Fi is a marketing and compliance certification for IEEE 802.11 technologies.The WiFi Alliance has tested compliant products certifies them for interoperability.

          Existing home wiring As an alternative to wireless networking, the existing home wiring (coax in North America, telephone wiring in multi dwelling units (MDU) and power-line in Europe and USA) can be used as a network medium. With the installation of a home networking device, the network can be accessed by simply plugging the Computer into a wall socket.

        Power lines The ITU-T G.hn and IEEE Powerline standard, which provide high-speed (up to 1 Gbit/s) local area networking over existing home wiring, are examples of home networking technology designed specifically for IPTV delivery. Recently, the IEEE passed proposal P1901 which grounded a standard within the Market for wireline products produced and sold by companies that are part of theHomePlug Alliance.The IEEE is continuously working to push for P1901 to be completely recognized worldwide as the sole standard for all future products that are produced for Home Networking.

HomePlug, Universal Powerline Association, HomePNA, HomeGrid Forum

Telephone wires: HomePNA, VDSL, VDSL2

Coaxial cables: DOCSIS, Multimedia over Coax Alliance (MoCA), and CWave carry data over coaxial cables, which are frequently installed to support multiple television sets throughout homes.

Network Devices

An example of a simple home network

A home network may consist of the following components:

Infrastructure devices

• A modem for connection to an Internet access service (either a DSL modem using the phone line, or cable modem using the cable internet connection).
• A residential gateway (sometimes called a broadband router) connected between the broadband modem and the rest of the network. This enables multiple devices to connect to the internet simultaneously. Residential gateways, hubs/switches, DSL modems, and wireless access points are often combined.
• A wireless access point, usually implemented as a feature rather than a separate box, for connecting wireless devices

Reference document: http://en.wikipedia.org/wiki/Home_network