lec1

• Conceptual Framework - Provides a structured approach to explain the interaction of networking devices.
• Conceptual Framework - Helps to visualize how networks operate and isolate network problems.
• Conceptual Framework - Explains the connectivity to understand the protocols

  and technology used in computer networks.
• Conceptual Framework - In networking, we have two most common frameworks—OSI and TCP/IP model.
• Physical Layer – responsible for transmission and

  reception of unstructured raw data between a device.
• Physical Layer – Handles data frames received from the Data Link layer into binary data bits of 1s and 0s.
• Data Link Layer -directly

  connected nodes are used to perform node-to-node data transfer where data is packaged into frames.
• Data Link Layer - encompasses two sub-layers of its own. The

  first, media access control (MAC), provides flow control

  and multiplexing for device transmissions over a

  network.
• Network Layer – responsible for receiving frames from the data link layer,and delivering them to their intended destinations among based on the addresses contained inside the frame.
• Network Layer - finds the destination by using logical addresses, such as IP (internet protocol).
• Network layer -At this layer, routers are a crucial component used to quite literally route information where it needs to go between networks.
• Transport Layer – manages the delivery and error checking of data packets.
• Transport Layer - This is where TCP(transmission control protocol) and UDP(user datagram protocol) takes place.
• Session Layer - controls the conversations between different computers.
• Session Layer - A session or connection

  between machines is set up, managed, and terminated at layer 5.
• Session layer - services also include

  authentication and reconnections.
• Presentation Layer - formats or translates data for the application layer based on the syntax or semantics that the application accepts.
• Presentation Layer - also called the syntax layer.
• Presentation Layer - This layer can also handle the encryption and decryption required by the application layer.
• Application Layer - At this layer, both the end user and the application layer interact directly with the

  software application.
• two most common frameworks

  • OSI
  • TCP/IP model.
• OSI Layer

  1. Application Layer
  2. Presentation Layer
  3. Session Layer
  4. Transport Layer
  5. Network Layer
  6. Data Link Layer
  7. Physical Layer
• TCIP / IP Model

  1. Network Interface
  2. Network
  3. Transport
  4. Application
• TCP/IP model - provides a practical approach
• OSI model - more theoretical.
• IP Subnetting - we are making the mask longer than the default for the IP class.
• IP Subnetting - creates sub-networks that allow for the efficient use of the address space.
• Routing - used for taking a packet from one

  device and sending it through the network to another network.
• Router uses routing table to make decisions.
• Routing can be manually or dynamically configured.
• Static Routing - manually enter route information and uses simple routing algorithms and provides more security than dynamic routing.
• Static Routing - does not handle failures in external networks well.