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Dante's Inferno but it's the 7 layers of the OSI model

#it #networking #computer networking #cisco #ccna #osi model

somehow I never posted this but have this incredible image I made a few years ago

#tech #osi model #because that's a hashtag that gets use

Every friend group needs a Router. Someone who can go Layer 3 and talk to other groups. A diplomat. An envoy. A bard.

#computer networking #osi model #shitposting #This still counts as studying

The Data Link Layer is the second layer of the Open Systems Interconnection (OSI) model, which serves as a conceptual framework that standar

The Data Link Layer is the second layer of the Open Systems Interconnection (OSI) model, which serves as a conceptual framework that standardizes communication system functions. This layer focuses on the reliable transfer of data between adjacent network nodes over a physical link.

#data link layer #network security #osi model #security #cybersecurity #learntorise #infosectrain

Explore the Seven Layers of Connectivity in the OSI Model

Unlock the mysteries of the OSI Model! Beginner-friendly guide to understand the layers and functions. Dive into networking fundamentals effortlessly.

Unraveling the OSI model: A symphony of 7 layers that harmonize digital communication. Discover the grand performance. 🎵 #OSIModel

#osi model #network communication #osi model in practice #layered model #data link #network layer #osi layers #internet protocol #data transmission #transport layer #session layer #presentation layer #application layer

OSI Model

OSI Model stands for the Open System Interconnection Model. This model is the model that was published by the ISO "International organization for Standardization" in the 1984. This Model is published just for communication purposes of the different vendors. There were the different devices that manufacturing were different and their pattern of the commination mismatch to each other. So OSI model published for the communication of the different vendors because it is open source so that is the reason this model called the

Open System Interconnection Model.

This Model is known as the theoretical model. This model is classify into the seven layers just for the easy understanding of the networking how the data propagate from sender to the receiver. So following are the seven layers of Open System Interconnection Model:

Fig: OSI Model

Application Layer

Presentation Layer

Session Layer

Transport Layer

Network Layer

Data Link Layer

Physical layer

Application Layer

Application layer is the 7th layer of the OSI Model and if we start the top to bottom then then it will make the 1st layer. So the mainly sequence that mostly common is bottom to top. Application layer is the layer that provide the user interface for user to interact. There are many applications in the computer field and if we see applications are divided into the two types: 1)Computer Application 2)Network Application. We need the network application for the communication and communication is necessary for the resources sharing. There are the multiple protocols that operate on this layer that are the following:

Http that use the port number 80.

Https that use the port number 443.

FTP that use the port number 20-21.

SSH that use the port number 22.

Telnet that use the port number 23.

SMTP that use the port number 25.

TFTP that use the port number 69.

Presentation Layer

Presentation layer is the layer that is the 6th layer of the OSI model and this layer concerns with the presentation of the data. presentation layer is the layer at which encoding of the data and decoding of the data occur and that layers also concerns with the encryption and decryption of the data. Compression and decompression of the data also a part of the presentation layer .

Session Layer

Session layer is the 5th layer of the OSI model and that layer is play an important role for the checking the availability of the destination. That layer is very important layer which is use to establish the session, maintain the session, and the terminating of session. The other main role of this layer is data synchronization of the session streams that are the multiple. This layer work as the dialog controller. This layer is the layer that can directly communicate with presentation layer and the transport layer.

Transport Layer

Transport layer is the layer that is known as the 4th layer of the Open Systems Interconnection Model. This is the layer that concern with the identifying of the service. The main functionality of this layer is Multiplexing and Demultiplexing. The process of segmentation of data also concerns with that layer. Sequencing and reassembling of the data happen on that layer. Flow Control and error correction are also occurring on that layer. TCP transmission control protocol and UDP user datagram protocol work on this layer.

TCP {Reliable, Connection Oriented, Slower than UDP}

UDP{Unreliable, Connectionless, Faster}

Network Layer

Network layer is the 3rd layer of the OSI model and that layer is most common and important layer of the OSI model. That layer is the layer on which our most important and effective device router works. Network layer is the layer that concern with the following :

Logical Addressing

Path Determination

Routing Protocols{RIP, RIPv2, OSPF, BGP, EIGRP}

Routed Protocols {IP, IPX, AppleTalk}

Datalink link Layer

Datalink link layer is the 2nd layer of the OSI model and here switch that is the networking device operate on this layer. Data link layer is the layer that concerns with the local delivery of the frames in between the devices. Here we see the most important protocols that are the following :

HDLC

HDLC stands for the Higher Level Datalink Control Protocol.

Cisco Proprietary.

No support Authentication, compression, and error correction.

PPP

PPP stands for the point to point protocol.

Standard Protocol.

Support Authentication, compression, and error correction.

Physical layer

This layer is the first layer of the OSI model. Physical layer is the layer that concern with the bits transfer of the from one medium to other medium. Hybrid Universal Broadcast device is the device that work on that layer. This layer concerning with how the bit converted into the signals.

#OSI Model #Physical layer #Datalink link Layer #Network Layer #Transport Layer #Session Layer #Presentation Layer #Application Layer

OSI-Based Cybersecurity Solutions Cyberattacks often target specific layers of your network stack. Understanding the OSI model helps identify vulnerabilities and apply proper controls. CQLsys Technologies helps organizations build layered cybersecurity strategies to strengthen protection across every network layer.