REV Flashcards
What are the four layers of the TCP/IP stack?
Application layer
Transport layer
Internet layer
Link Layer
What does TCP/IP
Transmission Control Protocol/Internet Protocol
What is the function of the application layer?
The application layer specifies what protocols need to be used
What is the role of the transport layer?
- Splits up data into packets
- Establishes end-to-end connection
what is the role of the internet layer?
Links the routers
What is the function of the link layer?
Adds the MAC addresses to the packets
What does the Memory Address Register do?
The MAR holds the address of a location that is to be read from or written to
What does the Memory Data Register do?
The MDR Temporarily stores data that has been read or data that needs to be written.
What happens during the fetch phase?
- The address from the PC is copied to the MAR
- Instruction held at that address is copied to the MDR by the data bus
- PC is incremented by 1
- The value of the MDR is copied to the CIR
Explain the Von Neumann Architecture
- Shared memory space for instruction and data
- Can only perform one instruction at a time
- Registers are used for fast access to instructions and data
Explain the Harvard Architecture
- instruction and data stored in separate memory units
- Each has its own bus
- Reading and writing data can be done at the same time as fetching an instruction
- used by RISC processors
What are the similarities and differences between paging and segmentation?
Both are used when RAM space is insufficient
Paging uses equal-sized sections called pages
Segmentation uses variable-sized logical sections called segments
What are the stages of compilation?
Lexical analysis
Syntax analysis
Code generation
Optimisation
What happens during lexical analysis?
- Whitespaces and comments are removed from the code
- remaining code is turned into a series of tokens
- symbol table is created to keep track of the tokens
What happens during syntax analysis
syntax analysis will produce an abstract syntax tree that checks that the code written has valid syntax