| Exaoctets per second (Eo/s) | Kibibits per second (Kibit/s) |
|---|---|
| 1 Exaoctet per second | 7.8125 × 1015 Kibit/s |
| 2 Exaoctets per second | 1.5625 × 1016 Kibit/s |
| 3 Exaoctets per second | 2.34375 × 1016 Kibit/s |
| 4 Exaoctets per second | 3.125 × 1016 Kibit/s |
| 5 Exaoctets per second | 3.90625 × 1016 Kibit/s |
| 10 Exaoctets per second | 7.8125 × 1016 Kibit/s |
| 20 Exaoctets per second | 1.5625 × 1017 Kibit/s |
| 25 Exaoctets per second | 1.953125 × 1017 Kibit/s |
| 50 Exaoctets per second | 3.90625 × 1017 Kibit/s |
| 100 Exaoctets per second | 7.8125 × 1017 Kibit/s |
| Reference | Exaoctets per second (Eo/s) | Kibibits per second (Kibit/s) |
|---|---|---|
| A dial-up modem | 7 × 10-15 Eo/s | 54.6875 Kibit/s |
| Typical home broadband | 1.25 × 10-11 Eo/s | 97656.2 Kibit/s |
| Gigabit Ethernet | 1.25 × 10-10 Eo/s | 976562 Kibit/s |
| Streaming a 4K film | 3.125 × 10-12 Eo/s | 24414.1 Kibit/s |
The exaoctet per second is a unit of data transfer rate equal to a thousand petaoctets per second, or eight exabits per second. Its symbol is Eo/s. Nothing built runs at this rate: it is about eight times the total traffic of the entire internet, counted across every network on the planet at once.
The unit is useful mainly for thought experiments about limits. If every hard drive and flash chip manufactured in a year were read simultaneously at full speed, the combined rate would be in this range. So would the total output of every camera sensor in every phone on Earth if they all recorded at once. These are sums over the whole world's hardware, not rates any system experiences.
There is one situation in which very large data volumes really do move faster than any network, and it puts the unit in perspective. Physically shipping a container of hard drives across an ocean transfers more data per second, averaged over the journey, than any cable. A shipping container holding a few exaoctets crossing the Atlantic in a week works out to several gigaoctets per second, and a truck of drives driven across a city beats almost any local link.
That calculation is not a joke; cloud providers offer it as a service. When a customer needs to move petaoctets into a data centre, the provider ships a lorry full of storage rather than attempting the transfer over a network, because the network would take months. The bandwidth of a vehicle is enormous, though its latency is measured in days.
For the unit itself, an exaoctet per second is 125 petaoctets per second, and it would transfer the world's entire stock of stored data — a few hundred zettaoctets — in about a week of continuous running. No mechanism exists to feed such a link, and none is being designed.
A converter must nevertheless handle the unit, because it appears in aggregate capacity models, in academic papers on the theoretical limits of communication, and in any table that lists the metric prefixes completely. A quantity does not need a use for its name to be well formed.
One exaoctet per second equals 1,000 petaoctets per second, 8 exabits per second, or about 0.8674 exbioctets per second.
The kibibit per second is a unit of data transfer rate equal to 1,024 bits per second. Its symbol is Kibit/s. It is the binary counterpart of the kilobit per second, and it is the least used member of an already unusual family, because transfer rates are one of the few places in computing where the decimal convention has always been unambiguous.
Networking has counted in true thousands from the beginning. A modem rated at 56 kilobits per second meant fifty-six thousand, not fifty-seven thousand three hundred and forty-four. The reason is that a transmission rate is set by a clock, and clocks are specified in decimal frequencies: a link running at ten million symbols per second carries a decimal number of bits, not a power of two.
The binary prefixes exist for quantities, not for rates, because quantities of storage are organised in powers of two while time is not. There is no natural reason for a rate to be a power of two, and consequently no reason for a rate unit to need a binary prefix. Where one appears, it is almost always because a program divided a binary file size by a duration.
That is exactly where the kibibit per second does turn up. A tool that measures a transfer by counting kibioctets and dividing by seconds produces a rate in kibioctets per second, and multiplying by eight gives kibibits per second. The unit is a consequence of the arithmetic rather than a description of the channel.
For scale, a kibibit per second is 128 octets per second, and the difference from a kilobit per second is 2.4 per cent — smaller than the measurement error of almost any real throughput test. At this level the distinction is technically correct and practically invisible, which is a fair description of the whole binary prefix system at its lower end.
The unit is properly defined and a converter must handle it, because the IEC series applies to every unit without exception. Whether anyone writes it is a separate question from whether it means something definite, and it does.
One kibibit per second equals 1,024 bits per second, 128 octets per second, or 1.024 kilobits per second.