Network Architecture
A set of layers and protocols is called the network architecture.
Protocol Hierarchies
• Networks are organized as layers to reduce design complexity.
• Each layer offers services to the higher layers. Between adjacent layers is an interface.
Design Issues for the Layers(functions)
1. Mechanism for connection establishment
2. Rules for data transfer
3. Error control
4. Fast sender swamping a slow receiver
5. Routing in the case of multiple paths
Network Protocols
• Protocol: is a format order of messages sent and received among the net entities and action taken on msgs transmission receipt.
• Protocol process :
1. The format or structure of the message
2. The process by which networking devices share information about pathways with other networks
3. How and when error and system messages are passed between devices
4. The setup and termination of data transfer sessions
Layering In Networked Computing
• OSI Model (open system interconnection)
• TCP/IP Model
Why a layered model?
1. Breaks down communication into smaller, simpler parts.
2. Easier to teach communication process.
3. Allows different hardware and software to work together.
4. Reduces complexity
The OSI model
The Open Systems Interconnection is the model developed by the International Standards Organization.
- helps us understand how data gets from one user’s computer to another.
-It aids to provide an organized structure for hardware and software developers to follow.
Why use a reference model?
– Serves as an outline of rules for how protocols can be used to allow communication between
computers.
– Each layer has its own function and provides support to other layers.
