Disclaimer: ChatGPT generated document.
To understand modern network performance, it helps to know a set of core metrics that describe how fast, reliable, and consistent communication is between two endpoints. The most commonly referenced ones are ping, latency, round-trip time (RTT), jitter, packet loss, throughput, and bandwidth. Below you’ll find an in-depth explanation of each, followed by the origin of their names, including the linguistic or historical roots of “ping” and “jitter.”
"Ping" is both:
- A network tool/command, and
- A measurement (colloquially).
Ping is a diagnostic tool that sends ICMP echo request packets to another host and listens for ICMP echo reply packets. It reports:
- Round-trip time (RTT)
- Packet loss
- Basic reachability (is the host up?)
Gamers and network users often refer to the RTT itself as “ping.” E.g., “My ping is 40 ms.”
Ping measures:
- Propagation delay (speed-of-light travel through fiber/copper/wireless)
- Processing delay (routers, NICs)
- Queueing delay (congestion)
- Transmission delay (time to push bits onto wire)
These delays summed together form the RTT, typically tens of milliseconds on consumer networks.
- In real-time applications (gaming, VoIP, remote robotics), latency under 30–60 ms feels “instant.”
- In cloud computing, API calls may be sensitive to even small increases in RTT.
- Satellite Internet often suffers ~600 ms RTT due to orbital distance.
Jitter is the variation in packet arrival times.
Mathematically, it is the statistical variance of latency over a sequence of packets. Example: If packets normally arrive every 20 ms but sometimes take 20, 21, 25, 19, 30 ms, the variation is jitter.
- VoIP and video conferencing use constant-rate streams; jitter causes choppy audio or video.
- Gaming can stutter or produce “rubber-banding.”
- Streaming uses buffers, but too high jitter still causes rebuffer events.
- Jitter buffers (VoIP)
- QoS (Quality of Service)
- Better routing or hardware
- Ping is one number (RTT)
- Jitter is how much ping changes packet to packet
Latency is the time it takes for one piece of data to travel from source to destination.
Latency can be:
- One-way latency: only measurable if clocks are synchronized with high precision
- Round-trip latency (RTT): what ping reports
Latency is caused by:
- Physical distance
- Router/switch processing
- Queueing during congestion
- Serialization delay (transmission)
Latency is a fundamental limit—fiber optic signals travel ~2/3 the speed of light.
RTT = the time from sending a packet to receiving its response.
Ping essentially measures RTT, not true one-way latency.
Packet loss occurs when network packets never reach their destination.
Causes:
- Congestion
- Wireless interference
- Router queue drops (tail drop, RED)
- Software bugs or hardware failures
Even 1–2% loss can severely impair:
- Gaming
- VoIP
- TCP throughput
Throughput is the actual amount of data transferred per second (e.g., Mbps).
This depends on:
- Bandwidth
- Latency
- Congestion window
- Packet loss
- Protocol behavior (e.g., TCP slow start)
Bandwidth is the maximum data rate of a link if it were fully utilized.
Bandwidth is a capacity; throughput is the realized performance.
| Concept | Means | Important for |
|---|---|---|
| Ping/RTT | Total delay (out + back) | Gaming, cloud |
| Latency | Delay (one-way or round-trip) | All networking |
| Jitter | Variation in delay | VoIP, streaming, gaming |
| Packet loss | Dropped packets | TCP, real-time |
| Bandwidth | Maximum capacity | Downloads, streaming |
| Throughput | Actual data transferred | Real-world performance |
Now the fun part.
“Ping” originally referred to a sharp, metallic, echo-like sound. This is the sound of a sonar ping used in submarines:
- A short acoustic pulse is sent,
- It reflects off objects,
- The returning echo indicates range (distance).
This is the direct inspiration for the network tool: Send a signal → wait for an echo → measure the time.
In computing, Mike Muuss wrote the original ping program in 1983 for BSD UNIX.
He named it explicitly after sonar:
“The name comes from the sound that sonar makes.”
There is a retroactively constructed acronym:
- Packet
- Internet
- Network
- Groper
Muuss explicitly said this was not the real origin — it came later as a humorous backronym.
So the true etymology is:
“Jitter” comes from early 20th-century English (possibly Scots-English), meaning:
- to shake
- to tremble nervously
- to move in rapid, irregular motions
It’s related to:
- jitters: nervous trembling
- jitterbug: energetic dance (swing music era)
In engineering, “jitter” was adopted by:
- Analog electronics
- Radio
- Telephony
- Oscilloscopes
…to mean irregular temporal deviation—the same meaning we use in networking today.
So the etymology is:
Comes from Latin:
- latēns → “hidden,” “lying dormant”
In the sense of:
- latent variables
- latent heat
- latent period
In networking, “latency” refers to the hidden time delay before data appears.
Originally from signal processing and radio engineering. The "band" refers to a frequency band, and “width” refers to how wide (in Hz) the band is.
More width → more data capacity.
From older English:
- through (end-to-end passage)
- put (to place/send/dispatch)
Meaning “how much gets through.”
- Ping: RTT measurement + diagnostic tool; named after sonar echo sounds.
- Jitter: Variation in packet timing; name comes from "jittery" (trembling/shaking).
- Latency: Delay; from Latin latēns (“hidden”).
- RTT: Round-trip time, what ping really measures.
- Packet loss: Missing packets.
- Bandwidth: Maximum data capacity of a link.
- Throughput: Actual delivered data rate.
If you'd like, I can also provide:
- Diagrams of packet timing
- Formulas for latency/jitter calculations
- Examples from gaming, VoIP, or cloud networking
- OSI layer mapping of ICMP/ping
- C++ code using raw sockets to implement a ping-like tool
Just tell me!