Various Local Roadway: Ethernet Hub

Various Local Roadway: Ethernet Hub

My old friend is a native of Indonesia and still lives there. The traffic is very bad there, partly because of the needs of many people who ... 2/06/2016

My old friend is a native of Indonesia and still lives there. The traffic is very bad there, partly because of the needs of many people who go home from work through the bay on the island of Sumatra. There is not enough bridges for the number of cars that will cross the bay. The solution: fill the bay with the ground and evenly across the bay. After that, there will be many paths so that people can cross it.

If you are trying to connect 10 PCs in a network, using a cross-over cable between the NIC, you will begin working on the same alignment bay in Sumatra. You know how the two computers can use the Ethernet NIC with Cross-Over cable to communicate. However, to connect to another PC, you will need a lot of Ethernet NIC, and your PC may not have enough space for all the cards. Additionally, you need to activate the cables between your PC and all other PCs, or at least call an electrician to turn the cables. If you are trying to do to 100 PCs on the same floor in a building, and each PC wanting to connect to each of two PCs, you will have 99 cables that are connected to 99 NIC in each PC!

An alternative way to insert the cable into each of two PCs is organize the cables from each PC to the wiring closet and to connect cable to networking devices, called Ethernet Hub. Ethernet Hub provides a variety of functions, but the main thing is allowing electricians to cabling each device to the hub by using only a single NIC and a single cable separately reduce wiring issues. They only hear an electrical signal that is coming, and when received, hub repeat the same electrical signal to each of the two devices are connected to the hub.

Ethernet hub repeating something he heard

As it looks like the picture above, User1 sends data to the hub, and the hub of a repeat of what is sent via cable to User1 User2 and User3. Just as simple as that!

The image above also shows the wiring, but it does not show the wiring circuit where the wire is used. Interestingly, expecting hub Straight-through Ethernet cabling between the hub and the PC itself. Why is that? People who make the hub knowing that the Ethernet NIC on the PC to send the twisted pair that uses pins 1 and 2 and received in the twisted pair that uses pins 3 and 6, and vice versa. Therefore, straight-through cable between a PC operated NIC and a hub.

Simple logic in the hub :

1. Receiving traffic on pins 1 and 2 on each physical interface.
2. When receiving, repeat the same electrical signal to the other port, unless the signal is receiving data.
3. When repeating port to another, repeat traffic to pins 3 and 6 so that the PC will be heard.

Transmit Bit Through Local Network

Transmit Bit Through Local Network

Back to the previous tutorial " reason for existence Networks ", you have seen an example where User1 opens a file that is stored ... 1/29/2016

Back to the previous tutorial "reason for existence Networks", you have seen an example where User1 opens a file that is stored on the disk drive User2. Furthermore, User1 print files to a printer connected to a computer User2, and finally, User1 save the file back to disk drive User1.

Use Server File/Print

So that the process is running, User1 and User2 must be able to transmit a series of bits stored in memory on a computer to another. A file is simply a collection of bits. So, imagine it using a word processing program on a single computer. You can open the file, read the contents, and edit and change files. Likewise, if you can send the same bit in the file to another computer over a network, then you or someone else can edit the file using the same word processing program on the computer. So, let the computer work, the network should be able to get a set of bits from one computer to another.

Controlling Bit Through Cables

To transmit a binary code from one device to another device, the devices generate electricity through the wire delivery. Electrical signal has many characteristics that can be controlled and changed by the NIC. Changing one value means a binary 1 and a binary 0 value means, allowing you to transfer data over the wire.

For example, imagine if both PC1 and PC2 have a NIC, and there is a single wire that mengoneksikan two cards. The thin wire, long pieces made of copper, and copper is able to mengonduksikan electricity very well. Now imagine if the encoding standard used by companies that cause the NIC established that binary 0 is represented by a power supply voltage of 5 volts and a binary 1 is represented by 10 volts. Encoding is a term that refers to a set of rules that define what kind of electrical signal to be made by the sender to implement the binary 0 and binary 1.

In the picture above, PC2 generate electricity in a wire. In this case, PC2 wants to send a binary value of 0101. So PC2 sends a signal of 5 volts, then 10 volts, 5 volts and 10 volts, because the encoding scheme imaginative in this example stating that the 5 volt mean 0 and 10 volts means 1. PC1, Another tip of the wire, felt the incoming electrical signals and interpret its electricity using the same set of rules to interpret the encoding as PC2 0101, to be exact.

Note that the graph shown in the figure above illustrates the different electrical voltage, or constant. Therefore, the X-axis (horizontal axis) present time, when the electric Voltage changed, the X-axis value immediately changes to the next.

utilization different and constant value, which subsequently changed rapidly to other value that allows (as shown above), is called digital transmission. To transmit a binary number, or binary digit, is very useful when the data transmission is done using digital transmissions.

The term bps (bits per second) often refers to the connection speed networking. Note when units are bits, not bytes. In fact, in particular LAN running at a much higher speed, with slow LAN transmit 10 million bits per second (Mbps, also called megabits per second).

How Standard TCP/IP Evolving

How Standard TCP/IP Evolving

As mentioned in the previous section, IETF manage the making of and agreement on standards and TCP/IP protocol. The core definition of the T... 1/28/2016

As mentioned in the previous section, IETF manage the making of and agreement on standards and TCP/IP protocol. The core definition of the TCP/IP protocol in written documents called Requests for Comments (RFC). Each RFC defines several protocols or standards that are important for TCP/IP model. The term "RFC" originated from the fact that everyone can give an opinion regarding the current protocol protocot it in the review before it becomes a standard. In fact, the document is placed on the Internet so that everyone can see and give an opinion before the document became an RFC.

If you want to see some RFC which consists of models of networking TCP/IP, you have to do is use the connection to http://www.rfc-editor.org, you will be in a website that allows you to view some or all of the RFC. Most people learn to TCP/IP by reading the other sources (such as this article) before reading the RFC, which shows the high technical nature of the RFC. The point is every people can learn these standards, understand, and implement it.

Some TCP/IP Protocol The Good Popular

When learning something new would be very helpful if we use the example - a particular example. TCP/IP protocol is composed of various individuals. TCP/IP is actually a combination of two of the most popular protocol in the TCP/IP model. The next two sections present a little background of the two protocols.
Transmission Control Protocol (TCP).

TCP Error Recovery

TCP provides several features, described in the next article, "Choosing Options Exspedisi when Menggangkut Goods Through Highway (Network)." However, considerations concerning some details at this time can help you in the overall concept of TCP/IP. The most impressive feature of TCP is error recovery, which works like the example in Figure 3.3. Figure 3.3 shows some imaginative protocol that is used as error recovery. Figure 3.6 shows images the same, but the details that are added to TCP.

To perform error recovery, TCP uses TCP header before user data. Note that the image above shows some square box, beginning with the word "TCP Header", and followed by "User Data". The header is a collection of overhead bits are added to the user data so that the protocol can do its job. For example, to perform error recovery, TCP packets need to be numbered. For numbered packets, TCP need a place to write down the number. Furthermore, TCP could give a number, called Sequence Number, the TCP header. TCP header part of a packet sent over the network.

TCP also set part of the header to control the number reply. TCP uses are ackowloadgement number in the header to tell the sender of the packet which get an error. Note that fred set the acknowledgment number on the number sign next packet expected to be received by user1. For example, when user1 show replies value 2, it means he gets the number 1 and number 2 hope to get next. Therein User2 know when to send the packet number 2 again. Process shows the expected next package, rather than lists of the last received packet, called forward acknowledgment.

How to build the Local Roadway (Network)

How to build the Local Roadway (Network)

So far, you have been reading how the network allows computers to communicate with each other. Software included in the network, the majorit... 1/27/2016

So far, you have been reading how the network allows computers to communicate with each other. Software included in the network, the majority are in the computer and the other is in the router. The network also includes hardware, such as network interface cards (NIC) in the PC, which is mentioned in the previous article, "Building Networks" that starts with planning. Finally, enter your network cabling, which provide physical equipment to transmit bits over a network.

In the United States, most of the city, all the states, and the US federal government has a department of transportation (DOT). Each DOT plan, build, and resolve the issue concerning the highway. You can learn a lot about networking by comparing network and roads.

Bit control through Roadway Network

I just returned from lunch at one of my favorite places. At lunch, I get in the car, drove to the restaurant, ordered my favorite food and go home.
When I arrived home, my wife said, "So you drive a car through the streets is very cold outside for lunch huh?" Yes, absolutely. Who cares way as what I went through? My goals are more important.

Indeed, to know networking properly, you need to know some basics about the networking of similar lines. If you feel really interested in what will be discussed in the next article, you probably belong to one of the people - those who really - really want a career in the technical field of networking. If not, you should at least know the concept - the concept so that you can communicate with the networking geek in the entire world and have a strong understanding of networking.

What is a Local-Area Network?

Local-Area Network (LAN) set up as a network where the devices of his software are relatively close to one another. Of course, the network, once again according to this article, including computers, software, hardware, and wiring that allows computers to communicate. Although the definition is accurate, you really do not get a detailed picture of the LAN and in this way.

simple LAN components

In this case, the LAN consists of multiple real elements. First, you need at least two computers. These computers must have networking software. Otherwise, computers will not be able to communicate. They also need the physical ability to transmit bits from one computer to another, here are needed cables and NIC in each computer.

No LAN simpler than this. A large LAN can be more complicated, with more components such as the HUB and Switch networking, you'll learn more in the next post.

Exclusive Network Model to Prevent People Penetrate Networking Devices

Exclusive Network Model to Prevent People Penetrate Networking Devices

Once upon a time, there is no network or computer. After that, the first computer made, but because no one else who can be invited Speaking,... 1/26/2016

Once upon a time, there is no network or computer. After that, the first computer made, but because no one else who can be invited Speaking, not necessary a network! Finally, the second computer is made, and the need for networking has been started.

Network began to be developed as part of any offer computer vendor in the late 1960s, and eventually popular in the late 1970s. Each vendor computer networking to create a model of its own, which helps the computer so that a vendor can communicate easily.

Arrival networking, the two largest computer vendor in the world is the International Business Machines (IBM) and Digital Equipment Corporation (DEC). Then, IBM make its own model of networking, called Systems Network Architecture (SNA), and DEC to make his own, cleverly called DECnet.

Models Exclusive Networking vendors and others that are similar to the model is very good, the model enables the creation and implementation of the network, and can be operated, but not perfect. Problems on the exclusive networking models is have the quality exclusive model. So, the IBM computer can not communicate with computers DEC. Imagine if the same thing happens on the phone, you will not be able to call your best friend if he's using a different phone vendors.

As you can see, if a company wants to have some IBM computers and some computers DEC, then the company must have a separate network. Although thought it might be silly for now, imagine if you can only afford to buy a Dell PC as Gateway PC can not speak to Dell. That's the problem facing Exclusive networking models.

Two solutions emerged, short-term and long-term. Short-term solution, in association with kindness, just a form of capitalism long: DEC adjust its computers with models of the IBM SNA. Why? At that time, IBM gross income is approximately 10 times larger. So, DEC makes software that convert between standard DECnet and SNA standards. Software was not good, but it can be operated.

DEC create an gateway "DEC to SNA", which enables the devices of DEC and IBM SNA to communicate. The term gateway refers to a wide variety of networking devices that typically change one standard to another standard. As you can see, computer DEC easily act like an IBM computer, which uses SNA networking models. DEC just write some software, it operates on a device called a gateway, which converts into a DECnet SNA and vice versa.