| Zebioctets per second (Zio/s) | Yottaoctets per second (Yo/s) |
|---|---|
| 1 Zebioctet per second | 0.00118059162072 Yo/s |
| 2 Zebioctets per second | 0.00236118324143 Yo/s |
| 3 Zebioctets per second | 0.00354177486215 Yo/s |
| 4 Zebioctets per second | 0.00472236648287 Yo/s |
| 5 Zebioctets per second | 0.00590295810359 Yo/s |
| 10 Zebioctets per second | 0.0118059162072 Yo/s |
| 20 Zebioctets per second | 0.0236118324143 Yo/s |
| 25 Zebioctets per second | 0.0295147905179 Yo/s |
| 50 Zebioctets per second | 0.0590295810359 Yo/s |
| 100 Zebioctets per second | 0.118059162072 Yo/s |
| Reference | Zebioctets per second (Zio/s) | Yottaoctets per second (Yo/s) |
|---|---|---|
| A dial-up modem | 5.92923 × 10-18 Zio/s | 7 × 10-21 Yo/s |
| Typical home broadband | 1.05879 × 10-14 Zio/s | 1.25 × 10-17 Yo/s |
| Gigabit Ethernet | 1.05879 × 10-13 Zio/s | 1.25 × 10-16 Yo/s |
| Streaming a 4K film | 2.64698 × 10-15 Zio/s | 3.125 × 10-18 Yo/s |
The zebioctet per second is a unit of data transfer rate equal to 1,024 exbioctets per second, or two to the seventieth power octets per second. Its symbol is Zio/s. It is the binary counterpart of the zettaoctet per second, and the two differ by 18.1 per cent.
A link running at this rate would transfer everything humanity has ever stored several times over in a single second. That is the plainest way to describe how far it lies beyond anything that exists, is planned, or has been seriously proposed. The unit is a name for a quantity, not a description of a thing.
It is worth being precise about why such names are still defined. A measurement system is a set of rules, and the value of a rule is that it applies without exception. The moment a system says that certain prefix-and-unit combinations are legal and others are not, every user must carry a table instead of a rule, and different users will carry different tables. Complete definition is cheaper and safer.
The physical obstacles are not merely large but qualitative. At a zebioctet per second, the energy needed to switch the required number of states, even at the thermodynamic minimum, becomes a substantial power; the practical figure for real electronics is many orders of magnitude above that; and the number of parallel channels required exceeds anything that could be built and cooled. These are not engineering targets.
The 18.1 per cent gap from the decimal unit continues the pattern that runs through the whole binary series. Each step multiplies the discrepancy by 1.024, so a convention that was harmless at the kibioctet has become, by this point, a difference no reader could overlook. Making that visible is the purpose the IEC prefixes serve.
In practice, a converter meets this unit only in a complete table or in a document exploring theoretical limits. Handling it correctly costs nothing and demonstrates that the tool applies its rules uniformly, which is the property that makes its ordinary answers trustworthy.
One zebioctet per second equals 1,024 exbioctets per second, 1,180,591,620,717,411,303,424 octets per second, or about 1.181 zettaoctets per second.
The yottaoctet per second is a unit of data transfer rate equal to a thousand zettaoctets per second, or eight yottabits per second. Its symbol is Yo/s. It is the largest transfer rate the metric system named for thirty years, and it stands at the point where the question stops being one of engineering and becomes one of physics.
The physical limits are real and can be stated. Any communication channel has a capacity set by its bandwidth and its signal-to-noise ratio, a result Claude Shannon proved in 1948. Pushing a rate higher means using more bandwidth, more power, or more parallel channels, and each of those has a cost that grows without limit as the rate does.
Energy sets the sharpest bound. Thermodynamics requires a minimum energy to distinguish one state from another at a given temperature, and although practical systems are many orders of magnitude above that floor, the floor is not zero. At a yottaoctet per second even the theoretical minimum becomes a substantial power, and every real system multiplies it by a large factor.
There is also a limit from the medium itself. A single optical fibre has a capacity ceiling set by non-linear effects in the glass, which grow with the light power carried, so raising the power eventually degrades the signal rather than improving it. Reaching a yottaoctet per second would require something like a hundred billion fibres running at today's records simultaneously, which is a construction problem rather than a communication one.
None of this makes the unit meaningless. It is properly defined, it converts by the same rule as every other, and it appears in discussions of theoretical limits and in complete tables of the prefix system. A measurement system that stopped naming quantities at the point where engineering stops would be less useful, not more.
Since 2022 the metric system has had ronna and quetta above yotta, so this is no longer the top of the ladder. That extension was driven by data quantities rather than by rates, and nothing in transmission has yet given a reason to write a rate above this one.
One yottaoctet per second equals 1,000 zettaoctets per second, 8 yottabits per second, or about 0.8272 yobioctets per second.