Performance Indices⚓︎
Speed⚓︎
Networking speed
?
The data (bit: 0
or 1
) transmission speed.
e.g. bps
or bit/sec
-- bits per second
Mbps
: 1,000,000 bit/s, is how many millions of bits a network can theoretically transfer each second.mbps
: 0.001 bit/s.kbps
: 1,000 bit/s.Gbps
: 1,000,000,000 bit/s.
Bandwidth⚓︎
Networking bandwidth
?
Maximum amount of data your connection can handle at a moment (normally a second).
e.g. Ethernet bandwidth: 10 Mbit/s
→ the maximum amount of data can be transferred in a second is 10 Mbit.
Throughput⚓︎
Networking throughput
?
The amount of data passing through a network (or channel, or interface) in a unit time.
e.g. We can understand it as real-time "traffic" on a "bandwidth lane". But the number of "cars" cannot be more than the number the "bandwidth lane" allows.
Delay⚓︎
Networking delay
?
The time (s
) required to travel from one end of a network to another end.
There are 4 types of delays, corresponding to the concepts shown in the picture above:
Transmission delay
The transmission delay
measures the speed of data.
It's the time from when the first bit of a file reaches a link to when the last bit reaches the link.
\(L\) is the file size (bits). \(R\) is the transmission speed (bits/sec).
Propagation delay
The propagation delay
measures the speed of the medium.
It's the amount of time a bit on the link needs to travel from the source to the destination, where the speed is dependent on the medium of communication.
\(D\) is the distance (meter). \(S\) is the propagation speed (meter/sec).
Queuing delay
The queuing delay
measures the buffering rate.
If a packet arrives at its destination and the destination is busy, it will not handle that packet immediately. Instead, the packet has to wait in the input/output queues
.
This delay depends on the following factors:
- The number of packets arriving in a short time interval.
- The transmission capacity.
- The size of the queue.
Processing Delay
The processing delay
measures the speed of the processor (router or host machine).
It is the time taken by a processor to process the data packet.
Round-Trip Time⚓︎
Networking Round-Trip time
?
The duration in milliseconds (ms), taken by the network to go from a start-point sending a request to the start-point getting the response that the end-point has received the data.
Bandwidth-Delay Product⚓︎
Networking bandwidth-delay product
?
References⚓︎
What are the different kinds of computing network delays?
Created: December 10, 2022 21:52:45