Conversion from 2 Yottaoctets per second to Megaoctets per second

Information about the Yottaoctet per second (Yo/s)

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.

Information about the Megaoctet per second (Mo/s)

The megaoctet per second is a unit of data transfer rate equal to one million octets per second, or eight megabits per second. Its symbol is Mo/s. It is the unit in which storage devices and their interfaces are rated, and the one a file manager shows while a copy is running.

Storage speeds fall naturally into this range. A mechanical hard drive sustains 100 to 250 megaoctets per second on sequential reads. A solid-state drive on the older interface reaches about 550, which is the limit of that interface rather than of the drive. A modern drive on the faster interface reaches several thousand, at which point the unit gives way to gigaoctets per second.

Interface speeds tell the same story from the other side. The successive versions of the universal serial bus have offered roughly 1.5, 60, 625 and 2,500 megaoctets per second at their nominal rates, and memory card standards have followed a similar path. A device is always limited by whichever of the two is slower, and matching them is the practical art of building a fast system.

For everyday sizes, one megaoctet per second transfers a photograph in a couple of seconds and a two-gigaoctet film in about half an hour. At 500 megaoctets per second the same film takes four seconds. That contrast explains why the perceived speed of a computer changed so completely when solid-state storage replaced mechanical drives, even though processors improved far less over the same period.

Sequential rates like these are the best case. Reading many small files instead of one large one costs far more, because each file requires locating its data and reading its record. A drive that sustains 500 megaoctets per second in sequence may manage only a few tens when copying a directory of thousands of small files, and that is where the difference between drive technologies is most visible.

The unit also describes the throughput of a busy network connection: a gigabit link delivers 125 megaoctets per second at best, so a fast local network and a fast drive are now comparable, and neither is obviously the limiting factor in a transfer.

One megaoctet per second equals 1,000,000 octets per second, 8 megabits per second, or about 0.9537 mebioctets per second.