Chapter 2: Network Models Flashcards
What is the First Principle of Protocol Layering Principles?
Bidirectional Comms
Each protocol layer must do opposite tasks, so it can send and receive information.
What is the Second Principle of Protocol Layering Principles?
Identical Objects
The object under each layer, at both sites, must be identical. This allows for logical connections.
What are Logical Connections in a network?
Logical connections allow devices to communicate with each other over long distances. They do so by following network protocols separate from PHYSICAL connections used to communicate network devices.
What is the TCP/IP Protocol Suite?
TCP/IP stands for Transmission Control Protocol / Internet Protocol. It is a hierarchical protocol, where each protocol has specific functionality. Composed of both hardware and software.
What are the five network layers?
- Physical Layer
- Data-Link Layer
- Network Layer
- Transport Layer
- Application Layer
What is the Physical Layer?
Converts data to signals that will be transported over a physical medium.
Logical unit: BITS.
What is the Data-Link Layer?
Transmits data between two devices on the same network.
Network devices are uniquely identified by a Media Access Control (MAC) address, assigned to network adapters.
Logical unit: FRAMES.
What is the Network Layer?
Transmits data to external networks.
Networks are given and identified by Internet Protocol (IP) addresses.
Logical unit: PACKET or DATAGRAM.
What is the Transport Layer?
Ensures that data from a process on one device is sent to the same process on another device. Identifies process via port numbers.
Logical unit: USER DATAGRAM (UDP) or SEGMENT (TCP).
What is the Application Layer?
Ensures end-users can communicate on a network via a protocol.
Logical unit: NAME, a string of characters that uniquely identifies network resources (such as a web address); easily understood by people.
