WHAT IS LAN?
A local area network (LAN) consists of two or more computers connected together in a building or home using software and hardware. A LAN is contrasted to a wide area network (WAN) such as the Internet, which covers a large geographic area. In a LAN, there is a main computer or server, and remote computers called clients. By creating a LAN in the home or office, computers on the LAN can share files, resources, and if desired, an Internet connection.
A LAN can be one of two types: wired or wireless. A wired LAN requires Ethernet cable to physically connect all computers on the network to a main device called a switch. A wireless LAN uses radio waves to communicate, eliminating the need for wires. Therefore, the hardware used in a LAN should all be of either the wireless or wired type.
A LAN is fairly easy to setup. All Microsoft operating systems since Windows 98 Special Edition (SE) have included built-in networking software. In terms of hardware, each computer requires a network interface card (NIC). A switch is also required. This is a device that resembles an external modem and directs information on the network. If the LAN will be talking to another network, like the Internet, a router is also required. Luckily, one can purchase an external DSL modem with a built-in switch and router, in wireless or wired configurations.
Desktop computers typically use internal NICs that slip into an available slot on the motherboard, while a laptop might use a portable computer (PC) NIC. This type of NIC resembles a thick credit card that can be inserted into the PC card slot on the laptop.
If the LAN is to be hard-wired, each NIC must have an Ethernet port for connecting an Ethernet cable. In a wireless LAN, each NIC might feature a small radio wave antenna. The server is hard-wired to the DSL modem, switch or router, while the clients can communicate wirelessly, if desired. If there is to be no connection to the Internet or any other LAN or WAN, a switch alone will be fine.
Once the LAN has been set up, an administrator can designate which files and programs can be shared on the LAN. Some areas of the server may be kept behind a firewall to prevent access. All traffic on the LAN, including email, Internet surfing and other activities, can be monitored by the administrator using various tools.
A LAN can be one of two types: wired or wireless. A wired LAN requires Ethernet cable to physically connect all computers on the network to a main device called a switch. A wireless LAN uses radio waves to communicate, eliminating the need for wires. Therefore, the hardware used in a LAN should all be of either the wireless or wired type.
A LAN is fairly easy to setup. All Microsoft operating systems since Windows 98 Special Edition (SE) have included built-in networking software. In terms of hardware, each computer requires a network interface card (NIC). A switch is also required. This is a device that resembles an external modem and directs information on the network. If the LAN will be talking to another network, like the Internet, a router is also required. Luckily, one can purchase an external DSL modem with a built-in switch and router, in wireless or wired configurations.
Desktop computers typically use internal NICs that slip into an available slot on the motherboard, while a laptop might use a portable computer (PC) NIC. This type of NIC resembles a thick credit card that can be inserted into the PC card slot on the laptop.
If the LAN is to be hard-wired, each NIC must have an Ethernet port for connecting an Ethernet cable. In a wireless LAN, each NIC might feature a small radio wave antenna. The server is hard-wired to the DSL modem, switch or router, while the clients can communicate wirelessly, if desired. If there is to be no connection to the Internet or any other LAN or WAN, a switch alone will be fine.
Once the LAN has been set up, an administrator can designate which files and programs can be shared on the LAN. Some areas of the server may be kept behind a firewall to prevent access. All traffic on the LAN, including email, Internet surfing and other activities, can be monitored by the administrator using various tools.
The advantages of a LAN in the office are manifold. By having a central printer, for example, a business can avoid buying individual printers for each workstation. Workflow is enhanced while being easier than ever to control and administer. Flexibility and creativity can also improve. A LAN is a win-win situation for management and employees alike.
A LAN at home is extremely convenient. Share programs, images, music and digital projects, and enjoy gaming. Share a high-end color printer, scanner or other equipment. If concerned about your children’s Internet use, a LAN is one way to supervise online activity.
A hard-wired LAN is more trouble to install, as it requires running a physical Ethernet cable from each client to the DSL, switch or router. However, a wired LAN is reliable and secure. A wireless LAN is easier to install and less expensive, but requires a few more steps in the software setup to ensure it is secure. It may also be slower than a wired LAN, but this depends on the wireless standard used, as newer standards effectively compete with Ethernet speeds.
A LAN at home is extremely convenient. Share programs, images, music and digital projects, and enjoy gaming. Share a high-end color printer, scanner or other equipment. If concerned about your children’s Internet use, a LAN is one way to supervise online activity.
A hard-wired LAN is more trouble to install, as it requires running a physical Ethernet cable from each client to the DSL, switch or router. However, a wired LAN is reliable and secure. A wireless LAN is easier to install and less expensive, but requires a few more steps in the software setup to ensure it is secure. It may also be slower than a wired LAN, but this depends on the wireless standard used, as newer standards effectively compete with Ethernet speeds.
WHAT IS WAN?
A Wide Area Network (WAN) is a network that spans a large geographical area, the most common example being the Internet. A WAN is contrasted to smaller local area networks (LANs) and metropolitan area networks (MANs). LANs are home or office networks, while a MAN might encompass a campus or service residents of a city, such as in a citywide wireless or WiFi network.
The Internet is a public WAN, but there are many ways to create a business model or private WAN. A private WAN is essentially two or more LANs connected to each other. For example, a company with offices in Los Angeles, Texas and New York might have a LAN setup at each office. Through leased telephone lines, all three LANs can communicate with each other, forming a WAN.
Routers are used to direct communications between LANs communicating on a WAN. The router, installed on the leased line, reads the "envelopes" or headers on each packet of data that passes through the WAN, sending it to the proper LAN. When the packet arrives at the LAN, a device called a switch sends the data packet on to the correct machine. Hence, the WAN acts like an interface between LANs for long-distance communication. A WAN that runs on a leased line is a private WAN, as there is no public traffic on the line.
Because leased lines are expensive, many businesses that require a WAN use an Internet Service Provider (ISP) to provide WAN access instead. In this case, each LAN in the WAN communicates through a standard digital subscriber line (DSL) account. The DSL Internet account uses an existing telephone line while sharing that line with the telephone.
A DSL-based WAN uses public Internet lines. To protect the WAN from intrusion, a Virtual Private Network (VPN) is set up. Using a VPN, all WAN traffic remains encrypted en-route through the Internet, and is decrypted only at its destination. This is referred to as "tunneling," because the WAN is creating a secure channel through a public space. Firewalls also block intrusion by hackers. This type of WAN is arguably the most popular because it is cost-efficient with great benefits. It operates at high transfer speeds and is an "always on" connection, providing 24/7 uptime for the WAN.
The least expensive type of WAN uses the Internet over a dial-up modem. This type of WAN is not as popular, since the price of DSL has decreased enough to become competitive with dial-up accounts. A dial-up modem only operates at 56 kilobits per second (kbps), while a standard DSL connection is about 20 times faster. A dial-up connection also cannot share telephone service. Finally, dial-up is not an "always on" connection. When offices are in different time zones, this can effectively reduce WAN uptime.
A WAN is an excellent way for companies to utilize geographically remote resources and centralize productivity. A leased line or affordable DSL-based WAN allows employees, field personal, and management full or restricted access to pertinent data twenty-four hours a day, seven days a week. Considering the negligible cost of DSL today, a WAN makes good business sense.
There are five classes of the IP addresses such as A, B, C, D and E and only 3 classes are in the use. Class D IP addresses are reserved for the multicast group ant cannot be assigned to hosts and the E class IP addresses are the experimental addresses and cannot be assigned to the people. Every IP address consists of 4 octets and 32 bits. Every participating host and the devices on a network such as servers, routers, switches, DNS, DHCP, gateway, web server, internet fax server and printer have their own unique addresses within the scope of the network.
TCP/IP protocols are installed by default with the Windows based operating systems. After the TCP/IP protocols are successfully installed you need to configure them through the Properties Tab of the Local Area Connection.
The binary address for the class A starts with 0. The range of the IP addresses in the class A is between 1 to 126 and the default subnet mask of the class A is 255.0.0.0. Class A supports 16 million hosts on each of 125 networks. An example of the class A is 10.10.1.1. Class A is used for the large networks with many network devices.
Class B
The binary address for the class B starts with 10. The range of the IP address in the class B is between 128 to 191 and the default subnet mast for the class B is 255.255.0.0. Class B supports 65,000 on each of 16,000 networks. An example of the class B address is 150.10.10.10. Class B addresses scheme is used for the medium sized networks.
Class C
The binary address for the class C starts with 110. The range of the IP addresses in the class C is between 192 to 223 and the default subnet mask for the class C is 255.255.255. Class C hosts 254 hosts on each of 2 million networks. An example of the Class C IP address is 210.100.100.50. Class C is used for the small networks with less then 256 devices and nodes in a network.
Class D
The binary addresses for the class D starts with 1110 and the IP addresses range can be between 224 to 239. An example of the class D IP address is 230.50.100.1
Class E
The binary address can starts with 1111 and the decimal can be anywhere from 240 to 255. An example of the class E IP address is 245.101.10.10
It is very important to know that all the computers in the same network segment should have the IP addresses for the same class i.e. form A, B or C.
IP Addressing Tips
The Internet is a public WAN, but there are many ways to create a business model or private WAN. A private WAN is essentially two or more LANs connected to each other. For example, a company with offices in Los Angeles, Texas and New York might have a LAN setup at each office. Through leased telephone lines, all three LANs can communicate with each other, forming a WAN.
Routers are used to direct communications between LANs communicating on a WAN. The router, installed on the leased line, reads the "envelopes" or headers on each packet of data that passes through the WAN, sending it to the proper LAN. When the packet arrives at the LAN, a device called a switch sends the data packet on to the correct machine. Hence, the WAN acts like an interface between LANs for long-distance communication. A WAN that runs on a leased line is a private WAN, as there is no public traffic on the line.
Because leased lines are expensive, many businesses that require a WAN use an Internet Service Provider (ISP) to provide WAN access instead. In this case, each LAN in the WAN communicates through a standard digital subscriber line (DSL) account. The DSL Internet account uses an existing telephone line while sharing that line with the telephone.
A DSL-based WAN uses public Internet lines. To protect the WAN from intrusion, a Virtual Private Network (VPN) is set up. Using a VPN, all WAN traffic remains encrypted en-route through the Internet, and is decrypted only at its destination. This is referred to as "tunneling," because the WAN is creating a secure channel through a public space. Firewalls also block intrusion by hackers. This type of WAN is arguably the most popular because it is cost-efficient with great benefits. It operates at high transfer speeds and is an "always on" connection, providing 24/7 uptime for the WAN.
The least expensive type of WAN uses the Internet over a dial-up modem. This type of WAN is not as popular, since the price of DSL has decreased enough to become competitive with dial-up accounts. A dial-up modem only operates at 56 kilobits per second (kbps), while a standard DSL connection is about 20 times faster. A dial-up connection also cannot share telephone service. Finally, dial-up is not an "always on" connection. When offices are in different time zones, this can effectively reduce WAN uptime.
A WAN is an excellent way for companies to utilize geographically remote resources and centralize productivity. A leased line or affordable DSL-based WAN allows employees, field personal, and management full or restricted access to pertinent data twenty-four hours a day, seven days a week. Considering the negligible cost of DSL today, a WAN makes good business sense.
IP Addressing
IP address is a unique identifier of a computer on TCP/IP networks and on the internet. Every computer requires a unique IP address to be a part of the internet and the IP address is provided by the internet service providers. Every IP address consists of the 32 bits and a binary system of 0s and 1s. The binary number system consist of only two types of digits 0 and 1. It is easier for us to remember the decimal numbers rather than the binary number system such as 011001101. On a same network segment, all the IP address share the same network address.There are five classes of the IP addresses such as A, B, C, D and E and only 3 classes are in the use. Class D IP addresses are reserved for the multicast group ant cannot be assigned to hosts and the E class IP addresses are the experimental addresses and cannot be assigned to the people. Every IP address consists of 4 octets and 32 bits. Every participating host and the devices on a network such as servers, routers, switches, DNS, DHCP, gateway, web server, internet fax server and printer have their own unique addresses within the scope of the network.
TCP/IP protocols are installed by default with the Windows based operating systems. After the TCP/IP protocols are successfully installed you need to configure them through the Properties Tab of the Local Area Connection.
IP Addresses Classes
Class AThe binary address for the class A starts with 0. The range of the IP addresses in the class A is between 1 to 126 and the default subnet mask of the class A is 255.0.0.0. Class A supports 16 million hosts on each of 125 networks. An example of the class A is 10.10.1.1. Class A is used for the large networks with many network devices.
Class B
The binary address for the class B starts with 10. The range of the IP address in the class B is between 128 to 191 and the default subnet mast for the class B is 255.255.0.0. Class B supports 65,000 on each of 16,000 networks. An example of the class B address is 150.10.10.10. Class B addresses scheme is used for the medium sized networks.
Class C
The binary address for the class C starts with 110. The range of the IP addresses in the class C is between 192 to 223 and the default subnet mask for the class C is 255.255.255. Class C hosts 254 hosts on each of 2 million networks. An example of the Class C IP address is 210.100.100.50. Class C is used for the small networks with less then 256 devices and nodes in a network.
Class D
The binary addresses for the class D starts with 1110 and the IP addresses range can be between 224 to 239. An example of the class D IP address is 230.50.100.1
Class E
The binary address can starts with 1111 and the decimal can be anywhere from 240 to 255. An example of the class E IP address is 245.101.10.10
It is very important to know that all the computers in the same network segment should have the IP addresses for the same class i.e. form A, B or C.
IP Addressing Tips
- A Network ID cannot be All 0s
- A host ID cannot be All 1 because this represents a broadcast address for the local network.
- Each host must have a unique host portion of the IP address.
- All hosts on the same network segment should have the same network id.
- A host address cannot be 127 because 127 has been reserved for the loop back functionalities.
