A Brief Exploration of the OSI 7 Layer Model

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This video explains the traditional OSI 7 layer network model and describes how the TCP-IP family of ioT protocols fit into the picture.

Hi, I'm Daniel Holmlund. In this video, we'll show you the traditional OSI 7 Layer Network Model and describe how the TCP/IP family of IoT protocols fit into the picture. 

The internet of things is introducing many new network protocols. Sometimes there are so many that it's difficult to know how and when they can be used. In addition, protocols that are not based on the traditional OSI 7 Layer Model are becoming more common, where they have advantages in IoT situations such as systems that require low power, long distance radio communications, or mesh networking. 

The physical layer, Layer 1, is responsible for the transmission of digital data bits from the physical layer of the sending device to the physical layer of the receiving device. Examples of Layer 1 technologies include ethernet cables, token ring networks, hubs, and repeaters. 

The data link layer, Layer 2, is responsible for transferring data between two adjacent network nodes and providing some error correction. Examples of data link protocols are the frame based Ethernet Protocol and the Point-to-Point Protocol, or PPP. 

The network layer, Layer 3, is responsible for providing the ability to transfer variable length and network packets from a source to a destination. This includes the ability to route between adjacent networks. Examples of protocols in this layer are IPv4 and v6, IPSec, the Internet Control Message Protocol, or ICMP, which enables traceroute and ping, and the Internet Group Management Protocol, which enables multicast groups. 

Layer 4 is the transport layer and it provides services such as the connection-oriented data stream protocol, reliability. flow control, and multiplexing. Most people will better know this layer as the TCP or UDP service layer. 

The next commonly used network layer is the application layer, or Layer 7, which provides an abstraction layer that specifies higher level protocols. Some of these include the classic internet protocols such as HTTP, FTP, MQTT, SMTP, IMAP, LDAP, DNS, SSH, TLS, and more. 

The OSI 7 Layer Model gives us a conceptual framework, which we can use to continue our exploration of how specific protocols fit into the internet of things. Thanks for watching. For more information, check out the links provided and don't forget to like this video and subscribe to the Intel Software YouTube channel.