LAN, WAN and Home Networking

LAN, WAN and Home Networking
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LAN, WAN and Home Networking
Residences typically employ one LAN and connect to the Internet WAN via an Internet Service Provider (ISP) using a broadband modem. The ISP provides a WAN IP address to the modem, and all of the computers on the home network use LAN (so-called private) IP addresses. All computers on the home LAN can communicate directly with each other but must go through a central gateway, typically a broadband router, to reach the ISP.
Other Types of Area Networks
While LAN and WAN are by far the most popular network types mentioned, you may also commonly see references to these others:
Wireless Local Area Network - a LAN based on WiFi wireless network technology
Metropolitan Area Network - a network spanning a physical area larger than a LAN but smaller than a WAN, such as a city. A MAN is typically owned an operated by a single entity such as a government body or large corporation.
Campus Area Network - a network spanning multiple LANs but smaller than a MAN, such as on a university or local business campus.
Storage Area Network - connects servers to data storage devices through a technology like Fibre Channel.
System Area Network - links high-performance computers with high-speed connections in a cluster configuration. Also known as Cluster Area Network.

Tuesday, May 20, 2008

Business Networking

Business network can be defined as a group of people that have some kind of commercial relationship. For example the relationships between boss-employee, buyer-supplier, and colleague-colleague.

According to experts, business networking functions best when individuals offer to help others to find connections, rather than "cold-calling" on prospects themselves. Business networking can take place outside of traditional business environments. For example, public places such as airports, restaurants, and movie line-ups provide opportunities to make new business contacts if an individual has good social skills.Contents [hide]
1 Purpose
2 Use of Social Networking Services
3 References
4 See also

Purpose

Once a company has assessed its core capabilities it can either flush its assets away or, can find itself in a situation where it cannot compete on attributes, as it doesn't have the necessary resources. Because of this, networks are formed to utilize the advantageous attributes, and the importance here is dependent upon a mutually beneficial relationship that significantly adds to the value of a firm's market offering. With this, there comes a critical responsibility to thoroughly analyze the respective competitors, as there are both significant opportunities and risks associated with network partnerships.

Another purpose for a business network is to expand ones knowledge base without extending ones hours for learning and accomplishing new tasks. By utilizing the experiences and knowledge of others within your business network you are able to work more efficiently in the areas of your own expertise. For example, having people with computer related skills, phone skills, psychology background, health background, financial background, legal background, and business can help bring information from each area to the table that each person can share and use to the benefit of their own business.

Sharing information and being involved in a group can help your business reach levels you couldn't alone.

There are many online networking services that can benefit most businesses, one popular site is Connect Buzz. Yet, there have been an increase in such networking sites that was kicked off by the very popular Linkedin brand and now very clever business networking sites have come into play that not just take into consideration online business networking, which as noted by critics of business networking sites, does not work very well, and combined it with a complicated algorithm that places members of a business network into offline (in real life) networking meetings. One of the pioneers in such a hybrid business networking model is Business Networking Me.

Use of Social Networking Services

As business is increasingly carried on across the globe, there has become a strong need for business networking to take place on a more virtual level. There are a myriad of social networking tools which have been created to fulfill these needs. Together with software which provides access to on-line meetings and instant messaging, people are able to both access and increase their networks of business professionals without traveling.

Social networking is a good way to find people to add to your own business network. People that can benefit from your knowledge and provide you with theirs.

Leverage of social media in corporations is an undeniable evolution in our corporate world. No one can ignore the fact that better connected people and better networked companies are more successful. Organizations with deeper alliances and partnerships lead over the ones that work on their own. The goal is to help teams, partners and alliances to get better connected to relevant parties.

Fox Business Network

Fox Business Network is a United States-based cable and satellite news channel that commenced broadcasting on October 15, 2007 at 5:00 a.m. Eastern Daylight Saving Time. It is owned by Rupert Murdoch's News Corporation. The network is available to more than 30 million people.News Corp chairman Rupert Murdoch confirmed the launch at his keynote address at the 2007 McGraw-Hill Media Summit on February 8, 2007. Day-to-day operations are run by Kevin Magee, executive vice president of Fox News; Neil Cavuto manages content and business news coverage.Murdoch had publicly stated that if the purchase of the Wall Street Journal went through and if it were legally possible, he would have rechristened the channel with a name that has "Journal" in it.[3] However, on July 11, 2007, the parent company, News Corp, announced that the new channel would be called Fox Business Network (FBN).[4] This name choice is because it better fits with the official business name of the Fox television network, Fox Broadcasting Company or FBC, and Fox News Channel had recently been branded FNC, as well as to avoid bad jokes stemming from an acronym such as BJ for Business Journal.[5]

The network is placed on channel 43 in the New York City market, an important market for financial news. It is paired with Fox News on the dial, which moved to channel 44. CNBC is on channel 15 under the Time Warner lineup in New York. [6] According to an article in MultiChannel News magazine, NBC Universal paid up to "several million dollars" in order to ensure that CNBC and Fox Business would be separated on the dial, and in order to retain CNBC's "premium" channel slot. [7] However, it is important to note that FBN is on only Time Warner analog in New York; in other markets, digital cable is required. [8] Verizon's FiOS TV, with 515,000 subscribers nationwide, also carries the network on its premier lineup, which most customers have. Dish Network does not carry FBN.

INTERNETWORKING CHALLENGES

Implementing a functional internetwork is no simple task. Many challenges must be faced, especially in the areas of connectivity, reliability, network management, and flexibility. Each area is key in establishing an efficient and effective internetwork.
The challenge when connecting various systems is to support communication among disparate technologies. Different sites, for example, may use different types of media operating at varying speeds, or may even include different types of systems that need to communicate.
Because companies rely heavily on data communication, internetworks must provide a certain level of reliability. This is an unpredictable world, so many large internetworks include redundancy to allow for communication even when problems occur.
Furthermore, network management must provide centralized support and troubleshooting capabilities in an internetwork. Configuration, security, performance, and other issues must be adequately addressed for the internetwork to function smoothly. Security within an internetwork is essential. Many people think of network security from the perspective of protecting the private network from outside attacks. However, it is just as important to protect the network from internal attacks, especially because most security breaches come from inside. Networks must also be secured so that the internal network cannot be used as a tool to attack other external sites.
Early in the year 2000, many major web sites were the victims of distributed denial of service (DDOS) attacks. These attacks were possible because a great number of private networks currently connected with the Internet were not properly secured. These private networks were used as tools for the attackers.
Because nothing in this world is stagnant, internetworks must be flexible enough to change with new demands.

Wireless Network Security

It seems that more and more home users are going with wireless networks rather than the tradition wired networks with wires hanging everywhere and running wild around the house and in the crawlspace. What seems like a good idea quickly turns into a nightmare if you don’t vamp up the security of your wireless network.

Speed is of the essence. Typically, one thing matters to new users of wireless, getting connected and browsing that first website. While wireless connectivity can accomplish this, it’s best to set up your wireless connection securely before venturing out into cyberspace. Below are some tips to help secure your wireless network.

Change the default admin password. Admin passwords are easily figured out by attackers when they are left as the default. Not changing your wireless admin password opens your network to attack and can lead to many problems depending on the attacker’s agenda.

Another wireless security measure you will need to take is turning on encryption. Enabling WEP encryption on your wireless network will help you protect your privacy and all your info won’t be floating around outside your home waiting to be picked up by a passerby. It’s important to remember that all your devices on the wireless network will need to have the same encryption. So find the strongest encryption possible that will work on all devices of the wireless network.

Stop the auto-connect feature. Do not allow your devices to auto-connect. Allowing auto-connect may connect to a network that you don’t particularly want. Example, you don’t want your laptop connecting to your neighbor’s network and sending info.

It’s also a good idea that you install firewalls on all devices that connect to the wireless network. Even if the wireless router is firewalled, it’s important to also install firewalls on all computers that are connected to the wifi network. It’s important that these firewalls be set up correctly and block any intrusions that may compromise your wifi network.

Position your wireless router close to the center of your home. Although the reach of wifi networks can vary greatly, it’s important to not allow the signal to float around great distances from the main access point. It virtually impossible to stop all leakage from exiting your home. But minimizing the risk to your wifi network will help to protect it.

Another good idea for wifi network security is to not allow broadcast of the SSID. Your router may have SSID broadcasting set up by default; however you should be able to change this setting in the configuration. This feature is only useful for mobile environments, and is not needed in home wifi networks.

These are just a few tips to securing your wifi network. It’s always a good idea to check for firmware updates to your router as new exploits and vulnerabilities arise. Some routers will have an auto update feature and it’s important to use it. Using auto update will help keep your wifi network secure without the need of remembering to check for updates.

Sunday, April 27, 2008

HISTORY OF NETWORKS

Before the advent of computer networks that were based upon some type of telecommunications system, communication between calculation machines and early computers was performed by human users by carrying instructions between them. Many of the social behavior seen in today's Internet was demonstrably present in nineteenth-century telegraph networks, and arguably in even earlier networks using visual signals.

In September 1940 George Stibitz used a teletype machine to send instructions for a problem set from his Model K at Dartmouth College in New Hampshire to his Complex Number Calculator in New York and received results back by the same means. Linking output systems like teletypes to computers was an interest at the Advanced Research Projects Agency (ARPA) when, in 1962, J.C.R. Licklider was hired and developed a working group he called the "Intergalactic Network", a precursor to the ARPANet.

In 1964, researchers at Dartmouth developed the Dartmouth Time Sharing System for distributed users of large computer systems. The same year, at MIT, a research group supported by General Electric and Bell Labs used a computer (DEC's PDP-8) to route and manage telephone connections.

Throughout the 1960s Leonard Kleinrock, Paul Baran and Donald Davies independently conceptualized and developed network systems which used datagrams or packets that could be used in a packet switched network between computer systems.

The first widely used PSTN switch that used true computer control was the Western Electric 1ESS switch, introduced in 1965.

In 1969 the University of California at Los Angeles, SRI (in Stanford), University of California at Santa Barbara, and the University of Utah were connected as the beginning of the ARPANet network using 50 kbit/s circuits. Commercial services using X.25, an alternative architecture to the TCP/IP suite, were deployed in 1972.

Computer networks, and the technologies needed to connect and communicate through and between them, continue to drive computer hardware, software, and peripherals industries. This expansion is mirrored by growth in the numbers and types of users of networks from the researcher to the home user.

Today, computer networks are the core of modern communication. The scope of communication has increased significantly in the past decade and this boom in communications would not have been possible without the progressively advancing computer network.

DISTRIBUTED DATABASE MANAGEMENT SYSTEM

It is the software system that permits the management of the distributed database and makes the distribution transparent to users. A Distributed Database Management System (DDBMS) consists of a single logical database that is split into a number of fragments. Each fragment is stored on one or more computers under the control of a separate DBMS, with the computers connected by a communications network. Each site is capable of independently processing user requests that require access to local data and is also capable of processing data stored on other computers in the network. Users access the distributed database via applications. Applications are classified as those that do not require data from other sites (local Applications) and those that do require data from other sites (global applications). We require a DDBMS to have at least one global application.

Wednesday, March 26, 2008