3 o'clock in the morning, midnight sleepy, suddenly heard the two ears buzzing, the body under the tatami mat rustling, thought in the dream, but awake, found and did not see what, still in the night, so confirm this is not in the dream. Then turned on the light, found a cockroach lying on the mat, two mosquitoes have not known the trace. Next to sleep small, I angry grabbed the cockroach ran to the bathroom a good meal ravaged, and then wanted to continue in the dream of those who did not complete the various about, but no longer sleep.
The thought of a moment will take the 528 bus through the abominable Shanghai Road, the heart is very uncomfortable. Every day this road is very congested, traffic lights and more, bus stop site and more, I so-called congestion prediction and the principle of avoiding plugging completely ineffective, this road really is to go which block. I don't know why I gave up the subway, probably because of the crowded bar, bicycles, battery cars, car this self-routing tool is not in the scope, because driving them will take up my time is not much. Anyway, it's not going to sleep, so let's talk about the high-speed network offload stuff.
As early as a few years ago, there was an idea why a train would stop? For the guest? Why do passengers who do not get off the bus pay a time cost for the passengers who get off? Of course, rail carriers will not consider this because they think it is an intrinsic delay, just as an IP packet enters the router's inherent delay in querying a forwarding publication. However, for freight, people may have some different ideas, a freight train opened a cargo station, the cargo door opened, the staff in the vehicle is not stopped in the state of the cargo to unload at the station one by one down, afraid of the goods broke? Cushion a spring mat. For the same example, you might consider dropping and airborne, or bomber bombing, have you ever seen a plane stop and throw something or throw someone? Is the load unloaded in the case of speed retention?
In the low-speed environment of freight and ordinary passenger transportation, the inherent delay cost of stopping is not very high, but it is completely different at high speed or even super high speed. For the passenger, of course, people can not say that like throwing goods in the premise of the train kept the people to drop down, there is a spring mat ..... But I think this is a technical problem, it can be completely solved. First of all, the direct idea is to get off the person himself in front of the station to jump, the result fell dead, and then in order not to fall dead, the following cushion some things, the result is still crippled, finally, considering the following all made completely soft things, the results are safe, but still be frightened .... Isn't that a little bit of a technology solution? People or those who get off the bus, the movement is still jumping down, the difference is the result.
Wouldn't it be better to take the "get-off" person to jump to the "soft air cushion" in front of the station?
You can imagine a confined container space, the person who will get off early into the container, and then the train before the arrival of the container unloading, the train itself does not slow down. As to how the container stopped or stopped, it was entirely its own business, didn't you find this a typical example of complete decoupling? Generally in the film we always see the scene of the fight on the train, usually the first half of the train has a bomb, the protagonist finally killed the villain, or the villain trapped in a bomb compartment, and then turn a handle, the second half of the train and the first half of the part, the first half continues to move at the same pace, After the second half of the friction itself stopped, and then it was a bang, the film is basically over. Is this not a typical example of high-speed unloading? Of course, except for the last bang.
Can be a car each of these drop-off containers on the side of the high-speed train, near the station will have a dedicated next passenger track and pick-up track, and then the train arrives at the first x meters, the container off to the next passenger track, at this time because the inertia of the next passenger container speed is still consistent with the train, but after that, it can The "small compartment" stops completely at the station. For passengers, there is no feeling of discomfort.
For pick-up, the principle is that these containers, in the station's pick-up track to speed up to a high-speed train at the same speed, and then hook on the train, passengers later into the train compartment. This is really stepless speed! Of course, the number of x meters mentioned above, when the pick-up container starts, these are to be carefully calculated. I'm just giving a little theory.
Passengers who do not get off the bus will no longer be disturbed by the passengers. I think it's a high-speed train! Real high-speed rail! If I were to go to Shenzhen from Shanghai, I would spend almost the length of the high-speed rail in Shanghai to Shenzhen divided by the speed of the high-speed rail, and this non-stop design allows the high-speed rail to travel as fully as possible, no longer affected by the station. It will only be subject to weather, as well as the non-resistance factors such as traffic control.
Rail traffic can be so, how about IP networks? The current technology is difficult!
But the optical network offload technology is indeed there, and one of the simplest examples will be understood. The multiplexing of optical networks is a wavelength-division multiplexing, which is the multiplexing of wavelengths, so unloading is a wavelength, separating a particular wavelength from a superimposed wave is entirely a physical process, and this does not require a delay at all! Optical separators, optical switches and so on the use of such a principle.
However, for IP networks, this electronic digital network is difficult to do. Even technologies such as Cisco's CEF do not affect forwarding traffic during the process of distinguishing between local and forward traffic, and routers or switches need to do a packet-by-packet detection to match a stream or a different strategy. What the high-end routers can do is make the detection process as fast as possible.
What's this whining about? IP network isn't that what it's supposed to be? As I said before, the high-speed environment in the separation of one, in the physical layer is the easiest to do, why to do in the IP layer, the IP layer brought complexity, but also brought a controllable. In the core transmission network, the fiber is not the IP message, it is more like the IP packet after the modulation of the physical layer of the stream. All kinds of XDM are essentially used in this separation overlay technology, in the chip inside, on the motherboard, in the access network, in the transmission network, you will find a lot of multiplexer, multiplexer, separators and other things, these things do things with the rail traffic stop unloading almost.
5:40, at this point in time, how many people are dreaming ....
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High-speed unloading of IP network, optical network and rail transit
