Network architecture
Students must be able to outline the OSI model and its seven layers: 1-Physical; 2-Data Link; 3-Network; 4- Transport; 5-Session; 6-Presentation; 7-Application.
The OSI model, or the Open Systems Interconnection model, is a framework used to understand how different networking protocols work together to enable communication between different devices on a network. It is divided into seven layers, each of which represents a different aspect of the communication process:
The Physical layer: This is the lowest layer of the OSI model and is responsible for transmitting raw data over a communication channel. It defines the physical characteristics of the network, such as the type of cables and connectors used.
The Data Link layer: This layer is responsible for creating a link between two devices on the same network. It ensures that the data being transmitted is error-free and provides flow control to prevent the sender from overwhelming the receiver.
The Network layer: This layer is responsible for routing data from one device to another across multiple networks. It determines the most efficient path for the data to take and can also provide error-checking and retransmission of lost data.
The Transport layer: This layer is responsible for establishing end-to-end connections between devices and ensuring that data is delivered reliably from the sender to the receiver. It provides error-checking, flow control, and segmentation of data into manageable chunks for transmission.
The Session layer: This layer is responsible for establishing, maintaining, and terminating connections between devices. It allows two devices to communicate with each other and synchronize their communication.
The Presentation layer: This layer is responsible for formatting and encoding data so that it can be understood by the application layer. It handles tasks such as data compression, encryption, and translation between different data formats.
The Application layer: This is the highest layer of the OSI model and is responsible for providing the interface between the network and the applications that use it. It provides the means for applications to request and exchange information over the network.
Students must be able to explain the role of standards to ensure network hardware interoperability, and discuss the similarities and differences between common network standards including wireless (802.11), Bluetooth (802.15.1) and ethernet (802.3).
Standards play a crucial role in ensuring network hardware interoperability, as they provide a common set of guidelines that all devices must follow in order to work together. Without these standards, it would be difficult for different devices from different manufacturers to communicate with each other.
Wireless (802.11): This is a family of wireless networking standards that specifies how wireless devices can communicate with each other over a wireless network. The 802.11 standards define different frequency bands and data rates that can be used by devices, as well as the protocols and security measures that should be used to ensure reliable communication.
Bluetooth (802.15.1): This is a wireless communication standard that is designed for short-range communications between devices. It is commonly used in personal devices such as phones, tablets, and laptops to connect to other devices such as headphones, keyboards, and speakers.
Ethernet (802.3): This is a networking standard that defines how devices can communicate with each other over a wired network. It specifies the type of cables and connectors that should be used, as well as the protocols and data rates that can be used for communication.
One key difference between these standards is the range of communication that they support. Wireless standards such as 802.11 and Bluetooth are designed for short-range communication, while Ethernet is primarily used for longer-range communication over wired networks. Another difference is the type of communication channel that is used: wireless standards use radio waves, while Ethernet uses physical cables. Finally, the types of devices that are typically used with these standards can vary: Ethernet is often used in larger networks with servers and workstations, while wireless standards are more commonly used in personal devices such as phones and laptops.