Networking Reviews

TCP/IP Model vs OSI Model

We have talked in other posts about the OSI model, which is the de-facto standard model for describing and implementing IP communication networks. You might be thinking that the OSI model was the original standard created when the first computer networks started to appear, but this is wrong. The TCP/IP model is older than the OSI, despite that the OSI is the most well known model today.

[Read more…]

Filed Under: OSI Layers Tagged With: osi model, tcp model, tcpip model

OSI Layer 7: Application Layer

The Application Layer is the one which interacts with the user. A Software application that implements a communicating component, uses the OSI Application Layer to establish the application’s communication. For example a word processor that does not have communications capabilities, would not be concerned with the OSI Application Layer. On the other hand, an application with communication capabilities (e.g a Web Browser), has to implement the OSI Application Layer standards.
[Read more…]

Filed Under: OSI Layers

OSI Layer 6: Presentation Layer

The main function of this layer is to define data formats, coding, and conversion functions that are applied to application layer data. These functions ensure that information sent from the application layer of one system would be readable by the application layer of another system. Encryption and compression of Data are also defined as Presentation layer functions. [Read more…]

Filed Under: OSI Layers

OSI Layer 5: Session Layer

The Session Layer starts, controls, and manages communication conversations (sessions). Communication sessions consist of service requests and service responses that occur between applications located in different network devices. These requests and responses are coordinated by protocols implemented at the session layer. The session layer creates ways to imply which flows are part of the same session and which flows must complete before any are considered complete. [Read more…]

Filed Under: OSI Layers

OSI Layer 4: Transport Layer

The Transport Layer (e.g TCP) provides reliable delivery of Data by using error checking, acknowledgments, flow control, and sequence checking. Multiplexing of incoming data for different flows to applications on the same host (for example, TCP ports) is also performed. Flow control in this layer ensures that the transmitting device does not send more data than the receiving device can process.

Examples of Layer 4 Specifications and Protocols
• TCP
• UDP
• SPX
• Port Numbers (e.g 80 for HTTP)

Filed Under: OSI Layers

OSI Layer 3: Network Layer

This Layer defines logical addressing (e.g IP address) in order to identify each endpoint in a network and provide end-to-end delivery of packets. Think of the Network Layer as the postal service in a country. When you want to send a letter to a friend, you just need to know the destination postal address (e.g destination IP address) and you send the letter. The postal service (e.g the Network Layer) will determine the path to the destination (e.g IP Path Determination) and take care of the delivery (e.g using IP Routing). The two endpoints do not need to know the exact path taken for the delivery of the letter.

This Layer also encapsulates data into Packets, and defines how to fragment a packet into smaller pieces to accommodate media with smaller Maximum Transmission Units. An IP Router works in this Layer, since it can use the IP address information to route packets.

Examples of Layer 3 Specifications and Protocols
• IP
• IPX
• AppleTalk

Filed Under: OSI Layers

OSI Layer 2: Data Link Layer

The Data Link Layer provides error detection and error recovery of the data flowing across the physical network link. The Specifications in this OSI Layer define network and protocol characteristics such as Physical addressing, network topology, error notification, flow control etc. The physical addressing defined in this layer determines how devices are addressed on the data link layer. An example of physical addressing is the MAC address which is hard-coded in all Ethernet Network Interface Cards (NIC). Each Ethernet NIC that exist in the world has a unique MAC address. The Data Link Layer also combines bits into Frames. Each Frame has a Layer 2 Header which includes the Source and Destination MAC addresses among other fields.

Examples of Layer 2 Specifications and Protocols
• IEEE 802.3 Ethernet
• HDLC
• Frame Relay
• ATM
• PPP

Filed Under: OSI Layers

OSI Layer 1: Physical Layer

The Physical Layer defines the Electrical, Mechanical, and functional specifications of the physical link used to connect the communication device on the network. This layer defines characteristics like voltage levels, data rates, maximum transmission distances, connectors etc.

The specifications in this Layer can be categorized as LAN or WAN: [Read more…]

Filed Under: OSI Layers

Recent Posts

  • VoIP Tutorial
  • In Review – Sylvania Netbook
  • Choosing the Right 7 Inch Tablet PC For You
  • Wireless Access Point Reviews – How and Why Standards Matter
  • Types Of Wireless Speaker Adapters

Categories

  • Cisco Certifications
  • Cisco Firewall
  • Computer Virus Education
  • General Technology
  • Home Computer Security
  • Home Network Setup
  • Home Security IP Cameras
  • Information Security
  • IP Network Tutorials
  • IP Telephony and VoIP
  • Network Security
  • Networking Acronyms
  • OSI Layers
  • Software Tools
  • Technology News
  • Troubleshooting
  • Usefull Network Info
  • Wii Game Console
  • Windows
  • Wireless Networks
  • XBOX and PS3 Networking
  • XBOX PS3 and Wii News

Copyright © 2023 · Contact · About · Privacy Policy

We use cookies on our website to give you the most relevant experience by remembering your preferences and repeat visits. By clicking “Accept All”, you consent to the use of ALL the cookies. However, you may visit "Cookie Settings" to provide a controlled consent.
Cookie SettingsAccept All
Manage consent

Privacy Overview

This website uses cookies to improve your experience while you navigate through the website. Out of these, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent. You also have the option to opt-out of these cookies. But opting out of some of these cookies may affect your browsing experience.
Necessary
Always Enabled
Necessary cookies are absolutely essential for the website to function properly. These cookies ensure basic functionalities and security features of the website, anonymously.
CookieDurationDescription
cookielawinfo-checkbox-analytics11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Analytics".
cookielawinfo-checkbox-functional11 monthsThe cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Functional".
cookielawinfo-checkbox-necessary11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookies is used to store the user consent for the cookies in the category "Necessary".
cookielawinfo-checkbox-others11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Other.
cookielawinfo-checkbox-performance11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Performance".
viewed_cookie_policy11 monthsThe cookie is set by the GDPR Cookie Consent plugin and is used to store whether or not user has consented to the use of cookies. It does not store any personal data.
Functional
Functional cookies help to perform certain functionalities like sharing the content of the website on social media platforms, collect feedbacks, and other third-party features.
Performance
Performance cookies are used to understand and analyze the key performance indexes of the website which helps in delivering a better user experience for the visitors.
Analytics
Analytical cookies are used to understand how visitors interact with the website. These cookies help provide information on metrics the number of visitors, bounce rate, traffic source, etc.
Advertisement
Advertisement cookies are used to provide visitors with relevant ads and marketing campaigns. These cookies track visitors across websites and collect information to provide customized ads.
Others
Other uncategorized cookies are those that are being analyzed and have not been classified into a category as yet.
SAVE & ACCEPT