OSI model

-
OSI model stands for a open system interconnection model which was developed by apra net. It consist of severn layer.
Application Layer
Resentation Layer
Session Layer
Transport Layer
Network Layer
Data Link Layer
Physical Layer
You can have better understanding with the following infographics

1. Physical Layer: Physical layer deals with the actual connectivity between the source and destination. If you're transferring data to another machine through LAN, physical layer is the Ethernet connection. The water in the sea connecting your place and destination is the physical layer in our case.

2. Data Link layer: In this layer data is broken down into pieces. That is your goods will be separated in various categories, say expensive goods, fragile and non fragile. This layer deals with breaking the data being sent and transmitting it through the physical layer. So goods being categorized and sent through the sea.

3. Network layer: Here the data being sent is organized. It also decides which protocols to use, tcp or udp. So in our case the different compartments of ship where you'll keep these goods is the network layer. It will also decide which generators and engines to be used while travelling (protocols).

4. Transport Layer: Transport layer gives you the best route, security and safest path to the destination. The transportation of data takes place here. So think of the coast guard as transport layer. He'll look after the connection, inform you if there's any danger and tell you the best route to your destination.

5. Session layer: The best way to remember a session is thinking of it as a Hangout or Yahoo messenger chat. When two people start communicating a session is created, as soon as one ends the chat or disconnects session is broken. Session layer creates a new session for a pack of data. So the time when our ships leaves our docks and till the time it reaches the destination is one whole session, assuming there are no problems during that interval. If your ships gets hijacked by pirates, session is terminated. If the destination blows up, session is terminated.
Session plays an important role in online transactions. In the very last step, where you need to enter OTP or your secure password to authorize the transaction, if you sit idle for more than 2-3 minutes without any activity, the session will terminate itself and the transaction will be unsuccessful.

6. Presentation Layer: There are times you send various file formats through the network like images or videos. Presentation layer deals with all this different files. It converts this data into a readable format for the destination. Think of a captain who's in charge of people from various races, countries and languages. He has to make sure everyone will reach to destination and can perform their work over there.

7. Application layer: Many people think of browsers as soon as they hear application layer. But application layers isn't the browsers or application you're using. In our case if browsers are taken then ships will be out application layer.
But application layer is not the browser but the common protocols used by the browsers. So application layer are not the ships but the common fuels these ships are using.

Comments

Post a Comment

Popular posts from this blog

Windows Defender

-
Image
Windows Defender Windows Defender is Microsoft’s proprietary anti-malware tool that is used in Windows 8.1 and Windows 10 by default. At the time of its creation, it used to be rather cropped and ineffective, which caused an outpouring of criticism. However, it has been seriously improved since then, so in 2019, it has much to be loved for. Especially, because it became one of the best free Antivirus in its segment. As of today, it is a full-featured antivirus product that provides strong malware protection and some useful extras. It is highly estimated by the world’s leading AV testing labs (though Avast free still scores higher ). Windows Defender detects and removes almost 100% of cyber threats without a heavy impact on the system performance. At the same time, the Defender still lacks some important features offered by top antivirus suites. Also, its performance is not completely flawless, especially when it comes to false positives. Finally, Microsoft doesn’t offer ...
Read more

What is subnetting And How it works??

-
Image
Subnet        The main purpose of subnetting is to help relieve network congestion. Congestion used to be a bigger problem than it is today because it was more common for networks to use hubs than switches. When nodes on a network are connected through a hub, the entire network acts as a single collision domain. Partitioning a single network can help relieve network congestion and increase security If you work inside a large organisation or business, particularly one spread across multiple branches, it's highly likely that it deploys a subnet. A subnetting, or subnetworking, is the process of splitting a single large network into two or more strands. This means that an otherwise mammoth and unwieldy network can be subdivided into smaller, more localised networks. First, a look at IP addresses IP addresses are comprised of a 32-bit number with values ranging from zero to 4294967295, split into four octets. In order for it to be...
Read more

How to Test an Ethernet Cable

-
Image
1. Purchase an Ethernet cable tester. There are many models you can purchase. Make sure it has a   battery in it and power it on. 2. Plug one end of the cable into the transmit jack. The transmit jack on the tester maybe be labeled "TX".   3.Plug the other end of the cable into the receiver jack.The receiver jack may be labeled "RX" on the device. Some testers have a detachable receiver you can use to test the cable across different rooms. 4 . Check the lights on the tester. Most testers will have 2 sets of 8 LED lights that correspond to the 8 pins on the transmitting and receiving end of the Ethernet cable. There will also be a G light for the ground. It will test each pin one at a time. If all 8 pins light up on both ends, the cable is good. If any of the lights do not light up on either end, this indicates a short in the cable. Don't worry if the G light doesn't light up. If the lights on either end flash out of order, this ...
Read more