Lecture Slides
IoT Lecture 4.pdf
Link Layer
Logical Link Control
- Responsible for channel coding and framing
- Framing adds headers and delimiters to network layer datagrams to transmit a meaningful representation to the receiver
- Channel coding uses Forward Error Correction (FEC) to embed redundant data in the headers
- However, there are often limitations to the correction capabilities, which refers to the maximum number of errors that can be detected and corrected in a given block of data.
- channel coding rate is the ratio of useful information bits to the total number of transmitted bits. A higher coding rate means more efficient transmission but less error protection, while a lower coding rate provides better error correction at the cost of efficiency.
Media Access Control
- Responsible for reliable delivery and link access
- how are frames received and transmitted over the physical channel?
- How the channel is shared between multiple endpoints?
- What are the source and destination endpoints?
Physical Layer
- responsible for procesinng the link layer frame by subjecting it to
- transmission
- propagation
- free (wireless) and guided (wireline)
- reception
Line Codes
- Transmission in wireline scenarios uses line codes