OSI Layers

The OSI, or Open System Interconnection, model defines a networking framework for implementing protocols in seven layers. A layer is a collection of similar functions that provide services to the layer above it and receives services from the layer below it. On each layer, an instance provides services to the instances at the layer above and requests service from the layer below. OSI reference model is now considered as a primary standard for internetworking and inter computing. Today many network communication protocols are based on the standards of OSI model.

The 7 layers of the OSI models can be divided into upper and lower layers.

Layer 7: Application Layer
The Application Layer is the OSI layer closest to the end user, which means that both the OSI application layer and the user interact directly with the software application. This is the layer that actually interacts with the operating system or application whenever the user perform network-related activities.  

Protocols: FTP, DNS, SNMP, SMTP, FINGER, TELNET, TFTP, BOOTP and SMB protocol are operated on the application layer.

Network Devices: Gateway network device is operated on the application layer.

Layer 6:Presentation Layer
Layer 6 takes the data provided by the Application layer and converts it into a standard format that the other layers can understand.

Network Devices: Gateway Redirector is operates on the presentation layer.

Layer 5: Session Layer
It establishes, manages and terminates the connections between the local and remote application


Protocols: The protocols that work on the session layer are NetBIOS, Mail Slots, Names Pipes, RPC
Network Devices: Gateway

Layer 4: Transport Layer

Protocols: These protocols work on the transport layer TCP, SPX, NETBIOS, ATP and NWLINK.
Network Devices: The Brouter, Gateway and Cable tester work on the transport layer.

Layer 3: Network Layer

Protocols: These protocols work on the network layer IP, ICMP, ARP, RIP, OSI, IPX and OSPF.
Network Devices: Network devices including Router, Brouter, Frame Relay device and ATM switch devices work on the network layer.

Layer 2:Data Link Layer

Protocols: Logical Link Control ,  Media Access Control
Network Devices: Bridge , Switch, ISDN Router, Intelligent Hub, NIC, Advanced Cable Tester

Layer 1: Physical Layer

Protocols: Protocols that work on the physical layer are ISDN, IEEE 802 and IEEE 802.2
Network Devices: Hubs, Repeaters, Oscilloscope and Amplifier works on the network devices.

Configure Guest network on dual band router - Netgear router

Open a Browser and in the Address box type www.routerlogin.com or 192.168.1.1

The Login window will prompt for the routers username and password. The default username is “admin” and the default password is “password”

Click Guest network b/g/n to configure the 2.4ghz wireless guest network
Check Enable Guest network to enable the feature
Check Enable SSID Broadcast to broadcast the network name
Check Allow guest network to share your network with other users
Check Enable Wireless isolation to isolate the Guest network from reset of the network

Click Guest network a/n to configure the 5ghz wireless guest network
Check Enable Guest network to enable the feature
Check Enable SSID Broadcast to broadcast the network name
Check Enable Video network if you will be streaming HD video
Check Allow guest network to share your network with other users
Check Enable Wireless isolation to isolate the Guest network from reset of the network

Configure Guest network - Netgear Router

Open a Browser and in the Address box type www.routerlogin.com or 192.168.1.1

The Login window will prompt for the routers username and password. The default username is “admin” and the default password is “password”

Click Guest Network.
Check Enable Guest Network to enable the feature on the router
Check Enable ssid Broadcast to broadcase you network name
Check Allow guest to access my local network to all the users to share your network with everyone.
Setup a SSID and configure the wireless security.

Windows 7 Disk Cleanup

1. Click the Start button and type Cleanup in the search box, then click 'Disk Cleanup' in the search results.
2. Disk Cleanup will run a quick scan of your hard drive to identify files that can be safely removed.

3. Tick the box next to the sections you'd like to clear up.
4. Click 'OK' and follow the on-screen instructions to clean your hard drive.

Windows 7 Disk Defragmentation

Disk Defragmentation increases the performance of your computer.
Click “Start>All program>Accessories>System tools>Disk Defragmenter” to run disk defragmenter

Click One by one and click Disk Defragment.
If you want windows to automatically do the defragmentation click configure schedule.

Change Windows update settings

click on Start>Control Panel>System and Security>Windows Update.
Click Change Settings which is on the left side of the screen.

 Change the Windows update settings.

Personalize Windows 7

Change Screen Resolution
Change Windows update Settings

change your screen resolution

1. Open Screen Resolution by clicking the Start button , clicking Control Panel, and then, under Appearance and Personalization, clicking Adjust screen resolution.
   

   

   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
    
2. Click the drop-down list next to Resolution, move the slider to the resolution you want, and then click Apply.
   
   

   

   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
3. Click Keep to use the new resolution, or click Revert to go back to the previous resolution.

Windows XP - No wireless networks found in range

If you get this message no network found in range on a laptop and if the computer got a built in wireless card, then the wireless switch on the computer is off.

If computer got a External adaper then try the following steps
1. disable and enable wlan
2. unplug and replug the adapter
3. reinstall the wireless adapter
4. try change the wireless settings on the router
5. take the laptop to any hot spot and check whether its finding any signal

windows XP - Validating identity

When you try connecting to the wireless network it says "validating identity"

and at the bottom of the system tray it says "windows was unable to find a certificate to log you on to the network"

This problem occurs when you have a enabled wep security on the router.
To Resolve the issue click Change Advance settings on the left of the screen.
Click the Wireless Networks tab. Select the wireless networks tab and click properties.

Under association uncheck The key is provided form me automatically and enter the network key and confirm network key. Click Ok.

Again select the network and click properties.
Go to the Authentication tab and uncheck Enable IEEE 802.1x. Then click OK.

The wireless connection will get connected automatically.

windows cannot configure - Click Change Advance Settings

" windows cannot configure the wireless connection ............Click change advance settings...............".
If you get this error message then click change advance settings on the left side of the screen.

Click the wireless networks Tab and click the Check box " Use windows to configure my wireless connection setttings". Click Ok and then search for the wireless connection

Windows Cannot configure - Enable Wireless Zero configuration

When you get this message " Windows Cannot configure the wireless connection .................. If you want windows to configure this wireless connection. Start Wireless Zero Configuration ( WZC ) service.........." Enable wireless zero configuration service.

To Start the Wireless zero configuration click Start > Run > Services.msc and start the wireless zero configuration service. To view the screen shot on how to enable WZC click Here.

Enable Wireless Zero configuration

Click Start > Run
Type services.msc

Right Click Wireless Zero Configuration and select properties

Select the Startup type as automatic and services status to started.

Remove Preferred Networks - windows xp

Start > Control Panel > Network Connection
Right Click Wireless Network connection and Select Properties

Select the Wireless Network and Click Remove

Windows XP

Wireless :
Connect to a wireless network
Manually Add Wireless Network
Remove Preffered Wireless Network
Enable Wireless Zero Configuration

 Troubleshooting :
Windows cannot configure - Enable WZC
Windows cannot configure - Click change advance settings
Windows XP - Validating Identity
No wireless network found in range

Manually Add wireless Network - Windows XP

Start > Control Panel > Network Connection
Right Click Wireless Network connection and Select Properties

Click the Wireless Network Tab and Click Add

Enter the Name SSID, Select the security options and enter the network key. Click OK to add the network.

The Network will be add to the preffered network list. Click OK to connect to the network.

Connect to a wireless network - windows XP

Click Start > Control Panel > Network Connection
Right Click Wireless Network connection and Select View Available Wireless Networks

Select the Wireless Network and click Connect

Enter Network Key and configure the network key, then click connect.

Setting Save does not match the Requirement

When you Tried Connecting to the wireless network you get a message " The settings save on this computer for the network does not match the requirement of the network".

To Resolve this problem you need to remove the preffered network and then connect to the wireless network.

Click Open network and Sharing center. On the Left side of the screen Click Manage Wireless Network

Right Click the network and click remove network

After removing the network go to connect to a network and try connecting to the wireless network.

Enter Additional Logon Information

When you tried connecting to the wireless network it prompts you for additional log on information. You get this message when wep security is enabled on the Wireless Router.

To Resole the problem you need to manually add the wireless network.

Click Start and Select Control Panel

Click on Network and Internet connection

Click Network and sharing center

On the Left side of the screen Click Manage Wireless Network

Click Add

Select Manually Create a Network Profile

Type the Wireless Network Name, password and click Next

Show successfully Added the Network. Click Close.

Windows will take some time to identify the network. Once the network is connected it asks you select the location. If the network is not connected then try restarting the computer.

Compare the Windows 7 Editions

Wireless Switch on Various Laptops

Windows Based Laptops:

Acer (General) - FN+F5
Acer Extensa 2000/2500 Series - Far right launch button above the keyboard
Acer Travelmate C Series - Far left hot key and then choose WLAN from menu that appears
Acer Aspire 1000 Series - Launch Keys above the keyboard
Acer Aspire 1640Z - Launch Keys above the keyboard
Acer Aspire 1690 - Launch Keys above the keyboard
Acer Aspire 2000 Series - Button on the front of the laptop
Acer Aspire 2012 - Launch Keys above the keyboard
Acer Ferrari 3000 - Button on the front of the laptop
Acer Ferrari 3020 - Button on the front of the laptop
Acer Ferrari 3400 - Button on the front of the laptop
Acer Ferrari 4000 - Button on the front of the laptop

Advent 7086 - Button next to the power button
Advent 7096 - Button next to the power button
Advent 7100 - Fn / F2
Advent 7104 - Fn / F2
Advent 7201 - wireless key top right and then Fn / F2
Advent 8117 - small slide switch on the front of laptop

Alienware M17x - Fn+F2

ASUS (General) -The Fn+F2 or F5 and some has a toggle switch to turn on and off the WIFI which is located on the left side of the laptop

Aspire 1000/1640Z/1690/2012 - Launch Keys above the keyboard
Aspire 16xx (General) the satellite-like launch button above the keyboard
Aspire 2000 Series (less Aspire 2012, See Above) - Button on the Front of the Laptop
Aspire 3005 on the lower right-hand side of your laptop
Aspire 5612 sliding button on the side of the laptop
Aspire 9302 the blue button on the left-hand side of the laptop
Aspire 94xx (General) the key found below the Lock key
Aspire One, in the lower right corner of the palm rest is a small strip with a picture of an antenna on it. An LED to the right of the strip lights to indicate the wireless is turned on.

BenQ Joybook 5000u-d09 - Fn / F12

Compaq Armada Services ---- Not Wireless
Compact presario ---- Button on the back
Compact presario M2000 ---- Button above the keyboard (antenna icon on button)

Dell (General) - FN,F2 or FN,F8 or FN,F12
Dell Inspiron series ---- Fn / F2
Dell Inspiron 500M ---- Fn / F2
Dell Inspiron 600M ---- Fn / F2
Dell Inspiron 1510 ---- Fn / F2
Dell Inspiron 5100 ---- NOT WIRELESS
Dell Inspiron 6000 ---- Fn / F2
Dell Inspiron 8600 ---- Fn / F2
Dell Inspiron 9300 ---- Fn / F2
Dell Latitude D400 ---- Fn / F2
Dell Latitude D500 ---- Fn / F2
Dell Latitude D600 ---- Fn / F2
Dell Latitude D610 ---- Fn / F2
Dell Latitude D620 ---- Fn / F2
Dell Latitude D800 ---- Fn / F2
Dell Latitude X300 ---- Fn / F2
Dell d630 latitude - toggle switch on the left side towards the front by the PCMCIA slots and headphone
Dell Vostro 1500 ---- big button on left side or rear side

e-machines M series - Fn+F2

E-System 3115 - Slide switch on front of laptop Also has Fn / F5 function

Gateway Laptop ---- Switch on side and then Fn / F2
Gateway 7805u FX - Wireless toggle is on front right. Software switch is Fn+F2.
Fn is not in normal position and is located on the bottom left of the keyboard where CTRL is typically located.

Gericom Cinema 16100 model use the Fn+F1 key combo

Fujitsu (General) - FN+F10
Fujitsu Siemens Amilo A Series - Button above the keyboard on top right
Fujitsu Siemens Amilo D Series - Button above the keyboard on top right
Fujitsu Siemens Amilo K Series - Not Wireless
Fujitsu Siemens Amilo L/EL Series - Fn / F1 to turn on/off
Fujitsu Siemens Amilo La Series - Fn / F2 to turn on / off
Fujitsu Siemens Amilo Li Series - Easy launch button (one of 3) on top of keyboard

HP/Compaq (General Older models) - Button on upper left on keyboard deck
HP/Compaq (General Newer models) - Button on lower left below keyboard
HP nc4000 ---- Button above keyboard
HP nc4010 ---- Button above keyboard
HP nc4220 ---- Button on left next to USB port
HP nc6000 ---- Button above keyboard
HP nc6220 ---- Button above keyboard
HP nx9010 ---- Button on front
HP omnibook 6200 ---- Button on the left

IBM T43 ---- Fn / F5
IBM X32 ---- Fn / F5
IBM thinkpad (General) - Most have software switch or button on left hand side.
IBM thinkpad (model not further identified) with wireless switch on front edge of case.

Lenevo ---- button on the front

Medion ---- Fn / F1

MSI General - Antenna-like button close to the power switch
MSI U100 - Fn+F11

Packard Bell EasyNote E2 ---- Fn / F1
packard bell: easy-note MV46/008 ---- Fn / F1 to turn on/off
packard bell MZ36-U024 ---- Fn / F2 to activate

PHILIPS General - Fn+F2 key combo
PHILIPS X54 - Antenna like button close to the power switch.

SAMSUNG General - Blue button found in the middle section of the keyboard

Sharp Laptops ---- Fn / F2 to activate

Sony Viao - Button on the front or right hand side or slide switch
Sony VAIO VGN-AX570G - Front left button

Targa Companion 811 ---- Fn / F2

Toshiba (General) - FN,F5 or FN,F8 or switch
Toshiba Eqium Series - Slide switch on front of laptop
Toshiba Libretto Series - Slide switch on Left hand side
Toshiba M1 - Switch on left towards front
Toshiba M2 - Switch on left towards front
Toshiba Portege Series - Slide switch on the left hand side
Toshiba Qosmio Series - Slide switch on the left hand side
Toshiba Quantium Series - Slide switch on the left hand side
Toshiba R100 - Switch on right hand side
Toshiba Satego Series - Slide Switch on the right hand side
Toshiba Satelitte - On the Front under lip then Fn / F8
Toshiba Tecra 2100 - Switch on left
Toshiba TE2000 - Switch on left
Toshiba Satelite has a physycal switch on front of case. FN+F8 shows wether wireless communications is enabled or disabled.




For MAC/Apple Based Computers

MAC OS X 10.5.x (Leopard)
Click on the: Apple Icon > System Preferences > Network > Airport > Airport Power - On/Off

MAC OS X 10.4.x (Tiger and Earlier)
Open MAc Hard Drive >; Applications > Utilities folder > Set the Configure pull-down to Airport.
Make sure the "Airport Power:" says On. (This is the status or your Mac's Airport card.)
If not, click "Turn Airport On" button.