"Peronet" based on pigeons is still the fastest way to transfer large amounts of information

Mail dove with a load of microSD-cards is able to transfer large amounts of data faster and cheaper than almost any other method

Note Trans.: although the original of this article appeared on the IEEE Spectrum website on April 1, all the facts listed in it are quite reliable.

In February, SanDisk announced the release of the world's first microSD flash card with a volume of 1 terabyte. It, like the other cards of this format, is tiny, only 15 x 11 x 1 mm in size, and weighs 250 mg. It can fit an incredible amount of data in a very small physical space, and you can buy it for $ 550. So that you understand, the first 512 GB microSD cards appeared just a year before, in February 2018.
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We are so accustomed to the speed of progress in the field of computing, that these increases in the density of drives are practically neglected, and sometimes they are honored with a press release and a couple of articles on blogs. More interesting (and likely to lead to more serious consequences) is how much faster our ability to generate and store data grows compared to our ability to transfer them over networks that are accessible to most people.

This problem is not new, and for several decades, various types of “hitronety” have been used to physically transport data from one place to another — on foot, by mail, or by more exotic methods. One of the data transfer methods that have been used extensively over the past thousand years is the carrier pigeons, capable of making a journey of hundreds or even thousands of kilometers, returning home, and using navigation techniques, the nature of which has not yet been precisely studied. It turns out that in terms of bandwidth (the amount of data transmitted over a specified distance over a certain time), pigeon-based “peronets” remain more efficient than typical networks.


From the “standard of transmission of IP datagrams by air carriers”

On April 1, 1990, David Weitzman proposed the Internet Engineering Council's Request for Comment (RFC) called " standard for transmitting IP datagrams by air carriers ", now known as IPoAC. RFC 1149 describes an “experimental method of encapsulating IP datagrams in air carriers,” and already has several updates regarding both service quality and transition to IPv6 (published April 1, 1999 and April 1, 2011, respectively).

Sending an RFC on April Fool's Day is a tradition that began in 1978 with RFC 748, in which it was suggested that after sending the IAC command to the telnet server, DONT RANDOMLY-LOSE server stopped randomly losing data. A pretty good idea, isn't it? And this is one of the characteristics of the April 1 RFC, explains Brian Carpenter , who led the CERN Network Working Group from 1985 to 1996, who chaired the IETF from 2005 to 2007 and now lives in New Zealand. “It should be technically feasible (i.e., not violate the laws of physics), and you should read at least the page before you realize that this is a joke,” he says. “And naturally, it must be absurd.”

Carpenter, along with his colleague Bob Hinden, also wrote the April Fools RFC, which described the IPoAC upgrade for IPv6 , in 2011. And even two decades after its appearance, IPoAC is still well known. “Everyone knows about air carriers,” Carpenter told us. “Once Bob and I talked at an IETF meeting about IPv6 distribution, and the idea of ​​adding it to IPoAC came about quite naturally.”

RFC 1149 , which originally defined IPoAC, describes the many benefits of a new standard:

Many different services can be provided through pecking prioritization. Additionally, there is a built-in recognition and destruction of worms. Since IP does not guarantee 100% delivery of packages, you can reconcile with the loss of the carrier. Over time, carriers are independently restored. Broadcast is undefined, and a storm can lead to data loss. It is possible to make persistent delivery attempts, before the carrier drops. Audit traces are generated automatically, they can often be found in cable trays and logs [ Eng. log means both “log” and “journal for records” / approx. trans. ].

The quality improvement update (RFC 2549) adds several important details:

Multicast though supported, but requires the implementation of the device for cloning. Carriers may be lost if they are located on a tree to be cut. Carriers are distributed on the inheritance tree. On average, TTL carriers are 15 years old, so their use in searches along the expanding ring is limited.

Ostriches can be considered as alternative carriers that have much greater capacity to transfer large amounts of information, but provide slower delivery and require bridges between different areas.

Additional discussion of service quality can be found in the Michelin Guide .

An update from Carpenter that describes IPv6 for IPoAC, among other things, mentions potential difficulties with packet routing:

The passage of carriers on the territory of carriers that are similar to them, without establishing agreements on equal information exchange, can lead to an abrupt change of route, cycling of packages and delivery not in order. The passage of carriers through the territory of predators can lead to a significant loss of packages. It is recommended to consider these factors in the routing table compilation algorithm. To those who will implement these routes, in order to guarantee reliable delivery, it is worth considering policy-based routing, bypassing the region with a predominance of local and predatory carriers.

There is evidence that some carriers have a tendency to eat other carriers and further transport the eaten payload. This may be a new method for tunneling IPv4 packets in IPv6 packets, or vice versa.

The IPoAC standard was proposed in 1990, but messages with mailing pigeons were sent much longer: the photo shows a mailing pigeon in Switzerland, between 1914 and 1918

It is logical to expect from the standard, the concept of which was invented back in 1990, that the original format for transmitting data via IPoAC protocol was associated with printing hexadecimal characters on paper. Since then, much has changed, and the amount of data that fit into the specified physical volume and weight has increased incredibly, despite the fact that the payload of an individual pigeon has remained the same. Pigeons are able to carry a payload that constitutes a significant percentage of their body weight - the average carrier pigeon weighs about 500 grams, and at the beginning of the 20th century they could carry 75-gram cameras for reconnaissance on the territory of the enemy.

We talked to Drew Lesofsky , a lover of pigeon racing from Maryland, and he confirmed that pigeons can easily carry up to 75 grams (and perhaps a little more) "during the day at any distance." At the same time, they can fly a considerable distance - one fearless bird keeps the world record for the pigeon, who managed to fly from Arras in France to her home in Ho Chi Minh City in Vietnam, having traveled 11,500 km in 24 days. Most carrier pigeons, of course, are not capable of flying so far. The typical length of a long track at races, according to Lesofsky, is about 1000 km, and the birds overcome it at an average speed of about 70 km / h. At shorter distances, sprinters can reach speeds of up to 177 km / h.

Putting it all together, we can calculate that if we load a carrier pigeon to its maximum load capacity of 75 grams with 1 TB microSD cards, each weighing 250 mg, then the pigeon will be able to carry 300 TB of data. Having traveled from San Francisco to New York (4130 km) at maximum sprint speed, it would have reached a data transfer rate of 12 TB / hour, or 28 Gbit / s, which is several orders of magnitude higher than most Internet connections. In the USA, for example, the fastest average download speed is observed in Kansas City, where data is transmitted via Google Fiber at 127 Mbps. At such a speed, it would take 240 days to load 300 TB - and in that time our pigeon would be able to fly around the globe 25 times.



Suppose this example does not look very realistic, because it describes some kind of overbong, so let's slow down. Take a more average flight speed of 70 km / h, and load the bird on half the maximum load in terabyte memory cards - by 37.5 grams. Still, even if we compare this method with a very fast gigabit connection, the pigeon wins. A pigeon will be able to go around more than half of the globe in the time it takes our file transfer to end, which means that it will be faster to send data to a pigeon literally anywhere in the world than to use the Internet to transfer them.

Naturally, this is a net bandwidth comparison. We do not take into account the time and effort to copy data onto microSD cards, load them onto a pigeon, and read data on the arrival of the bird at the destination. Delays are obviously high, so something other than one-way transmission will be impractical. The biggest limitation is that the carrier pigeon flies only in one direction and to one destination, so you cannot choose the target for sending data, and you also have to transport pigeons to where you are going to send them, which also limits their practical benefits. .

However, the fact remains that even with realistic estimates of the payload and speed of the pigeon, as well as the Internet connection, it is not easy to surpass the net carrying capacity of the pigeon.

Given all this, it is worth mentioning that the pigeons checked the data transfer in the real world, and they coped well with it. A group of users of Bergen Linux from Norway in 2001 successfully implemented IPoAC , sending one ping with each dove to a distance of 5 km:

Ping was sent at about 12:15. We decided to do an interval of 7.5 minutes between the packets, which ideally should have caused a couple of packets to remain unanswered. However, it didn’t go quite well. Our neighbor flew over the site a flock of pigeons. And our pigeons did not want to fly straight home, they first wanted to fly with other pigeons. And who can blame them for this, given that the sun came out for the first time after a couple of cloudy days?

However, their instincts won, and we saw how, having frolicked for about an hour, a couple of pigeons broke away from the flock and headed in the right direction. We rejoiced. And these were in fact our pigeons, because soon after that we received a report from another point that the pigeon had landed on the roof.

Finally, the first pigeon arrived. The data packet was carefully removed from its paw, unpacked and scanned. After manually checking the OCR and correcting a couple of errors, the packet was accepted as valid, and our glee continued.

For really large amounts of data (such that the required number of pigeons will become difficult to maintain), still have to use physical methods of movement. Amazon offers the Snowmobile service - a 45-foot shipping container on a truck. One Snowmobile can carry up to 100 PB (100 000 TB) of data. It will not move as fast as an equivalent flock of several hundred pigeons, but it will be easier to work with it.

Most of the people, it seems, are satisfied with the extremely slow download, and they are not very interested in investing in their own pigeons. This really requires a lot of work, says Drew Lesofsky, and the pigeons themselves usually behave, not like data packets:

GPS technology is increasingly helping pigeon racing fans, and we get a better idea of ​​how our pigeons fly, and why some fly faster than others. The shortest line between two points will be a straight line, but pigeons rarely fly in a straight line. They often draw zigzags, flying roughly in the right direction, and then adjusting the course, approaching the destination point. Some of them are physically stronger and fly faster, but a pigeon that is better oriented, has no health problems and is physically trained can outrun a fast-flying pigeon with a bad compass.

Lesofsky trusts pigeons enough as carriers of data: “I would surely send information with my pigeons,” he says, while taking care of error correction. “I would release at least three at once to ensure that even if one of them has a bad compass, the other two will have better, and as a result, the speed of all three will be higher.”

Problems with the implementation of IPoAC and the increase in reliability of fairly fast (and often wireless) networks means that most of the services that relied on pigeons (there were many) over the past few decades have switched to more traditional data transfer methods.

And because of all the preliminary preparations required for the pigeons to set up the data transmission system, alternatives comparable to it (like drones with a fixed wing) can become more viable. However, pigeons still have some advantages: they scale well, work for seeds, are more reliable, they have a very complex system for avoiding obstacles both at the software level and at the hardware level, and they are able to recharge themselves.

How does all this affect the future of the IPoAC standard? There is a standard, it is available to everyone, albeit a bit absurd. We asked Brian Carpenter if he was preparing another update for the standard, and he told him that he was thinking about whether pigeons could not tolerate qubits. But even if IPoAC is a bit complicated (and a little wacky) for your personal data transfer needs, all kinds of non-standard communication networks will remain necessary in the foreseeable future, and our ability to generate huge amounts of data continues to grow faster than our transfer capabilities.

Thanks to the user AyrA_ch for the tip-off on the information with his post on Reddit , and for the convenient IPoAC calculator , which helps to calculate how much the pigeons are ahead of other data transfer methods.