You have to deal with delays and lost packets
An overview of
The data is queued up in the router’s cache for processing (forwarding, etc.) :
- When the incoming speed is temporarily faster than the processing speed, but at least the cache is sufficient – this is the queue delay
- I can’t even fit in the cache, so I have to throw it away
It’s more of a signal than a problem
Four sources of delay
- Processing (proc), what it is, to whom it is sent, calculating and checking; The time is usually very short, less than milliseconds
- Queue delays, depending on congestion
- Time required for transmission, generally refers to calculation: L/RL/RL/R
- The speed of light (D/SD/SD /s) is 2/32/32/3
Care should be taken to distinguish between transmission delay and propagation delay
Think of it as a car passing a toll booth
Words you don’t understand:
Another packet loss
- Queue (also called buffer) The capacity of the previous link in the buffer is limited
- Packets that reach the full queue have no choice but to be dropped
- Lost packets can be retransmitted by the previous node, the source system, or not retransmitted at all
throughput
- The bits/time unit is used to describe the total transmission rate from sender to receiver.
- Instantaneous and average
- A link on an end path that limits the throughput of the end
Under the real network:
