Single PC to PC Lan or Laptop to Laptop LAN Wiring

In order to communicate among pc to pc  or Laptop to pc or pc to laptop through lan or other network two things must be needed to make this happen. One is the data transmission and another is the data reception.  In single PC to PC lan or laptop to laptop lan network no Hub or Switch is needed. Because there are only two network Interface card (NIC) which are needed to connected through single pc to pc lan or laptop to laptop lan connection scheme, hence  point to point connection is possible without having other extra equipment except the communication media.

Single PC to PC LAN

So we can use either 10base-T or 100base-TX standard for this. For 10base-T normal speed is 10Mbps. And with 100base-TX you can get speed up to 100Mbps. But 10base-T cat-3 cable can be used but in 100base-T cat-5 cable is recommended.  But it is always recommended to use 100base-TX standard for this single pc to pc or laptop to laptop or pc to laptop lan.

Both 10base-T and 100base-TX use one 2 pairs of cable from 4 pairs of UTP cable. They follow 568A and 568B wiring standards. To know more about this please read the previous article.

So the main thing is, we just have to make a cross cable connection for  this single pc to pc or laptop to laptop LAN. For making cross cable connection, the easiest way for 10base-T and 10base-TX is on the one end of the cable connect with RJ45 connector using 568A wiring standard and on the other end connect with RJ45 connector using 568B wiring standard.

Cross cable connection for Single PC to PC LAN

 The wiring is shown as below

Cross cable connection for Single PC to PC LAN

The overview of Single PC to PC or Single Laptop to Laptop can be understood form the below image.

Network Diagram of Single PC to PC connection

The pin numbering of the RJ45 connector is also very import. The below image will show how it is done.

RJ45 Numbering Scheme

This is how one should do the Connection scheme for making the single pc to pc or laptop to laptop connection easily without extra mechinary except communication media and the RJ45 connector.  

Setup LAN in windows 7

Before going through this procedure first go through the following procedures. Make your LAN cable connection; make sure whether you trying to connect with network or with a single PC; also make sure in which type of network you are going to be connected. The cable connections are different for both of them. Also check if you have NIC (Network Interface Card Installed); don’t worry without some exception NIC is provided as built in with every PC nowadays. Just make sure they are not out of order.

Now follow the following procedure:

Give a name of your computer and also give a workgroup name. For this go to Control Panel -> System and Security -> System or right click on the My computer and click properties. Then in bottom left side you see change setting option, click on it.

You see the following window. Here on computer description is not a important thing. You can keep it blank or provide anything similar to other computer. Form bottom side click on change.

System properties Window

On the next window you see the options for a computer name and workgroup name. Provide a unique computer name and a common workgroup name

Setting computer name and workgroup

If the workgroup and computer name are provided earlier then you not to do anything. If you provide them now then you will shown a message to restart your computer. Restart computer.

Now you have to configure the TCP/IP settings.

Go to Control Panel -> Network and Internet -> Network and Sharing Center from the left side you see some options. Click on the Change adapter settings shown in following image.

Adapter settings

Now you can see the all network profiles. Right click on the Local Area Network and select properties.

Local Area Connection Tab

From Networking tab select the Internet protocol version 4(TCP/IPv4) and double click on it. Then from the following widow provide a unique IP address subnet mask will be created on its own. But make sure every PC on the network posses the same subnet mask.

TCP/IP Settings

After completing click ok. Now connect you cable with you computer which is connected to network switch or Hub. And in a minute you will be connected with network.

Connect two PC or Laptop using Wi-Fi with windows 7

When you buy a PC or Laptop or Notebook nowadays it is most probable that it has built in Wi-Fi adapter (as mostly know). Wi-Fi products are too much popular in the area of modern wireless communication.  

Every wireless adapter possesses two common modes of operation.

a.      Ad-Hoc Mode and

b.      Infrastructure Mode

Both modes have each own way of application. In this case, when it is needed to connect one PC to another PC without third party media than the Ad-Hoc mode is application. It gives a way to communication in peer to peer fashion.

Now we will see how to connect two PC using Wi-Fi in Ad-Hoc mode.

First of all configure both PC in ad-hoc mode. Follow the following instruction to configure your PC in ad-hoc mode.

First go to system window. You find it in Control Panel -> System and Security -> System or right click My computer and see properties.

Click on change setting tab. You find it just right side of computer name, domain and workgroup setting ribbon.

You will find a window like as follow.

Change computer name and workgroup

From this system properties window in click on change button and in computer name provide a name as you wish. The name should be unique as your computer will be shown in the network using this name. Also provide a workgroup name or you can keep the existing one. But the main thing is the other computer workgroup should be the same. Click ok. Restart the computer if you change anything. Otherwise don’t.

Now go to Control Panel -> Network and Internet -> Network and Sharing Center

From the change your network setting group click on set up a new connection or network

Setup a new connection

From the options select setup a wireless ad-hoc (computer-computer) network.

Select ad-hoc network

Click on next then you see another page. Provide a network name and a security type for personal security to restrict access of unauthorized personal. If you chose a security type then you need to provide a security key which you have to provide in other PC. You can keep things simple by selecting no authentication (open).

Ad-hoc network profile settings

Check the save this network check box if you want to keep it for future use. Now click on next. You see a message showing configuration completed.

Setup complete message

Now you have to configure the TCP/IP settings of your wireless adapter. Go to Control Panel -> Network and Internet -> Network and Sharing Center and from left side click Manage Wireless Networks. First select you ad-hoc profile and then click on adapter property.

Wireless adapter selection

Do as illustrated in the following picture set the IP address and default gateway as shown.

TCP/IP settings

Do the same things on the other PC but keep the following things on mind

Both computer names must be different.

Workgroup will be same.

Network name must be same.

On IP address settings interchange between IP address and default gateway. If you set in one computer IP address as 198.168.0.1 and default gateway as 198.168.0.2 then set IP address of second computer as 198.168.0.2 and default gateway as 198.168.0.1

after configuration of both PC you are ready to connect.

For making connection go to Control Panel -> Network and Internet -> Network and Sharing Center and click on connect to a network. Select your profile and click connect. Don’t forget to active both Wi-Fi.

Selection Window

Connection Window

Whenever other PC will be in the range then it will be connected.

Introduction to Wi-Fi Network

Wireless network standardized by IEEE802.11 and certified Wi-Fi Alliance use radio waves for communication. In wireless LAN (WLAN) devices both transmit and receive radio signal and hence they referred as station. In Wi-Fi network generally there are two modes of operation is available. One is Ad-hoc mode and the other is infrastructure mode. 

Through Ad-Hoc mode stations can communicate with each other without any third party control as peer-to-peer fashion. For an example we need to connect with some computer through LAN. If they have build in Wi-Fi then you just have to enable ad-hoc mode to make the connection, no need for any cable connection or switch. This mode is well for temporary network and has some limitation. The function of ad-hoc mode is limited.

On the other hand infrastructure mode makes connections among other stations through wireless access point (WAP) which also connect a wired network with a wireless network. In a simple word access point is a device that allows stations to connect wirelessly within certain limit range. 

The data rates of Wi-Fi network differs according to which generation technology it uses. Now a day up to fourth generations technology available in Wi-Fi networks. It comes with different 802.11 wireless network standards. They are as follow:

Wi-Fi Technology with 802.11a works with frequency band of 5 GHz and use OFDM as coding technique which basic principle is to make segments of radio signal into several sub-signals then transmit. That reduces interference. Data rate is up to 54 megabits per second.

802.11b comes with CCK modulation technique and operates in 2.4 GHz frequency. But its use is limited in modern days because of its low speed which is 11Megabits per second. 

802.11g is similar with 802.11b in a way they both use same frequency band 2.4GHz but with OFDM technique 802.11g improves its speed up to 54 megabits per second.

The latest standard is 802.11n can use both 2.4GHz and 5 GHz frequency band and transfer data in rate of 140 Megabits per second which making it popular now a day.

What is Wi-Fi and Wi-Fi Certification?

The international standard IEEE802.11 describe the specification of Wireless Local Area Connection simply WLAN. Wi-Fi stands for wireless fidelity. Wi-Fi alliance is a group that run Wi-Fi certified program which goal is to testing products whether they are compatible with 802.11 industry standards. And the Wi-Fi certified Logo is the assurance that the product is compatible with other vendor’s hardware devices that undergoes with 802.11 standards. These things are often misunderstood by us. Simply a product using Wi-Fi logo confirms us that it undergoes the Wi-Fi certification with success. And Wi-Fi itself is not any standard. And also not a manufacturer brand. Different manufacturer brands are making these wireless devices and after the Wi-Fi certification the use this Wi-Fi certified logo.

Wi-Fi certification test products according to product capability. Now a day there are fourth generation technology available they are as follow.

Standard	Frequency	Maximum Data Rate
802.11a	5 GHz	54 Mbps
802.11b	2.4 GHz	11 Mbps
802.11g	2.4 GHz	54 Mbps
802.11n	2.4 GHz, 5 GHz, 2.4 or 5 GHz (selectable), or 2.4 and 5 GHz (concurrent)	450 Mbps

There are some other additional capabilities too.

Wi-Fi Certified Logo with color coded indicator Icon

 

So before buying any product with Wi-Fi certification makes sure the vendor is in Wi-Fi certification list. And look the Wi-Fi certified logo with color coded indicator Icon on product. Otherwise you may lose. 

Wireless Networking with Ad-Hoc Mode

Networking is the most popular concept for resources sharing. It means creating connection among network devices. Network devices like computer, Printer etc can be connected with network through wired or wireless medium. The most common network we see is LAN where computers are connected through UTP cable. This can be done easily through wireless Ad-Hoc mode easily. Wireless network uses radio signals or microwaves for communicating with other wireless devices and a perfect example of peer to peer network concept.

For an example now a day’s all Laptops and desktops have built in Wi Fi devices. So whenever you need to connect with another Laptop or desktop with in Wi Fi range you just need to set it up, no need for cable LAN connection.

Each wireless network comes up with two distinct modes. They are the Infrastructure mode and the Ad-Hoc mode. Ad-Hoc mode gives the wireless devices the privilege to communicate with each other. 

For setting up communication each wireless adapter must be configured in Ad-Hoc mode.  Also the SSID for all AD-Hoc network devices must be the same. Service set identifier (SSID) identifies a particular 802.11 wireless LAN. 

It has some advantage over wired network such as easy, portable, cost effective, AD-Hoc mode wireless network is good for temporary or emergency purpose where the number of devices is less. But as the traffic or the no of connected devices increases its performance become decrease. 

Another limitation is speed. Such as Ad-Hoc Wi Fi network support 11Mbps where other Wi Fi network support 54Mbps or more. Wireless devices in Ad-Hoc modes offer minimal securities. Also all the devices must be situated in the wireless range. Also bad weather, wall and some other environmental condition effect the wireless ranges.

The difference among Hub, Bridge, Switch and Router

These are most common words uttered when we talk about network. Sometime we confuse our self which for what. This is because all the four have some similarity but they are not same. To understand a network we need understand about their working principle.

Hub

It is the least expensive and intelligent network device compared with others and in modern days not used too much. It has a very simple working principle. It just passes the information packet to all. Not sense anything, not take any decision.

For an example suppose five computers are connected through Hub in a LAN network. If No 1 computer transmit a packet of information to no 3 computers then Hub just pass all the information to all four computers. It is then up to computers to decide whether it will take the packet or not.

This simplified operation creates unnecessary traffic and make the network slow.

Bridge

As the name suggest bridge links two points. It is upgraded version of Hub that just not passes information but also take some decision. Bridge has only two ports. Normally bridge is used to link two networks. It has the capability of taking decision whether the information should go other side or not. It can sense both side destination and find out whether the destination is in the same side or on the other side. If it is on the same side then bridge does not allow the information to pass through it hence reduce traffic. It can be used to link two networks where traffic between them is low.

Normally two types of bridge used. Transparent bridges are used to link two same type of Network where Translation bridges are used to link to different Network.

Switch

Switch is the upgraded version of bridge with multi port support and content addressable memory.  With this Content addressable memory (CAM) a Switch can easily find out the correct destination and send the data packet only to it. It increases the performance dramatically.

A switch always maintains dynamic CAM. Whenever a network device connected through it port it save the devices MAC address in its CAM table. So it always knows the addresses of all connected device. Hence it becomes easy for a switch to take decision where the packet will go.

Router

Router works a little bit different from others. As its name suggest it finds the best possible way or route for your message to go its destination. For this router use IP address instead of MAC address and also can surf through different protocols.

Introduction to Network Topology

When talking about topologies, sometime beginners confused with the physical and logical topologies of network. Simply Network’s physical topology means the physical connection scheme or cabling scheme among network devices. On the other hand logical topology handles the communication scheme through physical topology. But before understanding the topologies you should first look at the networking devices for better understanding.

Some physical topologies are described below:

Point to point

It is device to device direct networking scheme. In this topology two devices are connected directly and can communicate directly. Multiple connections are not possible. Some examples of point to point network topology: single pc to pc LAN scheme, when you connect two routers across WAN.

Point to point physical topology

Star topology

When network needs many devices to connect through network then star topology may be used. In this topology many devices are connected to each other through a central device which has much point to point connecting port.

10baseT Ethernet uses star topology with Hub or switch in its center. Star network capacity can increase through extended star.

In extended star several star networks are interconnected.

Star Topology

Extended Star Topology

Bus topology

In bus topology all network devices are connected through a single cable. Some older Ethernet scheme like 10base2, 10base5 use bus topology.

Bus Topology

Ring topology

In ring topology the cabling of the network complete a close ring hence it is so named. Like firs device is connected to second device, then second device connected to third device and will go on up to last and then the last device will be connected to first device and complete the ring.

Ring Topology

What is logical topology?

Logical topologies, simply the total data flow process in the network. They are strictly controlled by network protocol. Same network may have distinct physical and logical topology. Means, network with physical star topology may work on bus logical topology.

Consider a simple network connecting with star physical topology using hub. As we know hub is the least intelligent device that simply passes information or data comes to it to all others connected through it. So every connected device sees everything. We can logically simplify its physical star diagram as shown in the image below. We see it’s a typical bus topology. So though it is physically a star but logically it’s a bus topology.

Simplified Star physical topology with equivalent Logical Bus topology

Introduction to Power over Ethernet (PoE)

It is an IEEE802.3af Standard defined in 2003 for supplying low voltage power to networked devices through the communications line. It was defined as Data Terminal Equipment (DTE) Power via Media Dependant Interface (MDI). But it is now a day most commonly referred as Power over Ethernet (POE).

The basic idea of Power over Ethernet (PoE) is, for providing uninterrupted network the end devices must be powered up. For this we have to place all the end devices in the places where AC power output is available. Or AC power line needs to be laid up to end devices. So it is a limitation for placing network end devices as per requirement. PoE has come over to solve this limitation and give the network end devices power without additional power line but through the communication line that carries data. 

PoE increased the mobility and reliability of network end devices, also reduce cost and improve safety aspect. The installation process also got simplified with PoE.

It uses two techniques to carry power to network end devices.

a.       Alternative A

b.      Alternative B

With Alternative A method power is carried through same cable with data and with Alternative B method power is carried through unused cables.

These techniques are implemented with two types of devices. They are PSE and PD. PD stands for Powered Device that receives power through Ethernet and PSE stands for Power Sourcing Equipment. The PD operating voltage is 48VDC which is supplied by PSE. So they can be categorized as SELV circuit. SELV stands for safety extra low voltage as its voltage not exceed from 60VDC. The maximum current supplied by PSE is 350mA. And it provides up to 12W at 48VDC to each PD.

Endspan and midspan these two types of PSE system normally used. Generally endspan PSE is used in new installation and midspan PSE used to add PoE capability in network.

The Crossover connections

Now a day’s in almost every home, Educational Institute and office UTP cables are used mostly as transmission medium of LAN. There are different types of UTP cables available in the market. Normally it is recommended to use category#5 UTP cables. In every UTP cable there are 4 pairs of different color cable. 

TIA/EIA-568A and TIA/EIA-568B are the two standards for cabling telecoms product in commercial building. They define the UTP colored cable numbering. According to them the numbering system is as follow:

TIA/EIA-568A Standard		TIA/EIA-568B Standard
Cable no	Color code	Cable no	Color code
1	white and green	1	white and orange
2	green	2	orange
3	white and orange	3	white and green
4	blue	4	blue
5	white and blue	5	white and blue
6	orange	6	green
7	white and brown	7	white and brown
8	brown	8	brown

There are two cabling method available, straight through and cross cable connection. 

cross cable connection between Hub

cross cable connection between two single PC

From the picture we see that crossed cable is used in a LAN network to connect switch/Hub to switch/Hub or a single PC to PC connection. Normally two different types of cross cable connection are seen in a LAN network. The reasons for their differences are as follow:

We can divide the LAN connection standards in two categories. In one category, the standard that required only two pairs two transmit and receive and in another category standards that need all four cables for transmitting and receiving.

On first category the standards will be 10base-T, 100bast-TX etc as they need only two pairs of cable to transmit and receive. Their cable specifications are as follow:

10base-T and 100base-TX crossed connection
Connection:1   TIA/EIA-568A Standard				Connection:2       TIA/EIA-568B Standard
Pair	Pin no	Color code	Action	Pair	Pin no	Color code	Action
1	1	white and green	BI_DA+	1	1	white and orange	BI_DA+
	2	green	BI_DA-		2	orange	BI_DA-
2	3	white and orange	BI_DB+	2	3	white and green	BI_DB+
	4	blue			4	blue
3	5	white and blue		3	5	white and blue
	6	orange	BI_DB-		6	green	BI_DB-
4	7	white and brown		4	7	white and brown
	8	brown			8	brown

From the table we see that in only 4 cables are used and the others are unused. So it does not matter how we connect the unused cable. But according to standard they normally connected with same no of cable of other side.

Simply the cross connection then appears as follow:

cross cable connection for 10base-T and 100base-TX

On the other category we can found 100BASE-T4 or 1000BASE-T as they used all four cables for communication. So no cables remain unused. So in cross cable connection of these standards they need to cross too. But the most interesting thing is still this type of cross cable can be used for 10base-T and 100base-TX connection. Because it does not matter for these standards how the unused cables are connected. So this type of cross cable connection can be used for all standards. Hence this the most recommended cross cable connection. 

Crossed connection for TIA/EIA-568A

10base-T, 100base-TX, 100base-T4 and 1000base-T  crossed connection
Connection:1   TIA/EIA-568A			Connection:2    TIA/EIA-568A Crossed
Pin no	Color code	Action	Pin no	Color code	Action
1	white and green	BI_DA+	1	white and orange	BI_DB+
2	green	BI_DA-	2	orange	BI_DB-
3	white and orange	BI_DB+	3	white and green	BI_DA+
4	blue	BI_DC+	4	white and brown	BI_DD+
5	white and blue	BI_DC-	5	brown	BI_DD-
6	orange	BI_DB-	6	green	BI_DA-
7	white and brown	BI_DD+	7	blue	BI_DC+
8	brown	BI_DD-	8	white and blue	BI_DC-

Crossed connection for TIA/EIA-568B

10base-T, 100base-TX, 100base-T4 and 1000base-T  crossed connection
Connection:1   TIA/EIA-568B			Connection:2    TIA/EIA-568B Crossed
Pin no	Color code	Action	Pin no	Color code	Action
1	white and orange	BI_DA+	1	white and green	BI_DB+
2	orange	BI_DA-	2	green	BI_DB-
3	white and green	BI_DB+	3	white and orange	BI_DA+
4	blue	BI_DC+	4	white and brown	BI_DD+
5	white and blue	BI_DC-	5	brown	BI_DD-
6	green	BI_DB-	6	orange	BI_DA-
7	white and brown	BI_DD+	7	blue	BI_DC+
8	brown	BI_DD-	8	white and blue	BI_DC-