The Magic Of Networking and It’s Wonderful Story part-1 :
every time I am using a tool like WiFi or internet connection like 4G or LTE , or while I am using my TV remote . I am asking myself how things really works . and the most important thing and really intersting for me is which path the my HTTP requests takes to the server exactly like while asking on google as example .Or How My cellular phone calls really works .
Network :
refers in math to Networks, a graph with attributes studied in network theory . in general . network in the compute sience used to refer to a group of nodes : computers , phones , TVs , that are connected using files or non-files connection .
Human Being Communication :
I started believing that to understand the present we need to understand the past it is really a big travel to go through all the history of human beign communication but this gonna help us to understand networking .
Communication : a process by which information is exchanged between individuals through a common system of symbols, signs, or behavioris . usually between animals of a single species, but it can also happen between two animals of different species . Animals communicate using signals, which can include visual; auditory, or sound-based; chemical, involving pheromones; or tactile, touch-based, cues . In the case of human Beings things are more complicated . Human communication is strikingly different from any other known natural communication system. From an evolutionary perspective, this is particularly striking because, biologically, humans are primates whose communication system has evolved during a long and shared phylogenetic history. One way to investigate the roots of human language is with comparative studies of primate cognition, particularly the basic processes required for language production and perception. A key feature of any language definition is that, during acts of communication, signallers draw their recipients’ attention to what they consider relevant entities, both real or imagined . but now we have one primte rule : “ any kind of communication need a tool that can be understandble by all people that are communicating ” . with time and while people take a bigger space in the world the necessity of tool that we can communicate using it comes .
the act of communicating over distance is called tele-communication :
TeleCommunication :
Using signals : The Fires, Smoke Signals, and Horns :
Some of the most common methods of communicating in prehistoric times included using fires, smoke signals, and even horns to capture the attention of others. Using fires and smoke helped individuals to share their locations and to seek out assistance when they were in trouble or looking to be found. Horns were used to help communicate times and important events that took place within growing communities and tribes. Using smoke signals was also helpful to track when groups were moving from one location to another, since they did not have the luxury of maps or the ability to search a location within minutes with technology like we have today.
Polybius said : “ the power of acting at the right time , contributes very much of the success of entreprises , and the fire signs are the most efficient of all devices , which aid us to this .”
A fire of signal is great when the space of possible message is small . such as ATTACK or NO ATTACK . and as the number of messages possible to send the need to communicate many diffrences born .
from the art of war the greek Built some methods :
1-those who are about to communicate urgent news to each other by fire signals should procur two vessels of exactly the same width and depth and through the middle should pass a rod graduated into equal sections , each clearly marked off the next denoted with the greek letter . each letter would correspond to a signal message in a look-up table which contain the most events that occur in the war .
2-Two people separated by a distance each have 10 torches separated into two groups of five. To begin, the sender raises a torch and waits for the receiver to respond. Then the sender lights a certain number from each group of torches and raises them. The receiver then counts the number of torches lit in the first group. This number defines the row position in an alphabetic grid they share. And the second group of torches signifies the column position in this grid. The intersection of the row and column number defines the letter sent. Realize this method can be thought of as the exchange of two symbols. Each group of five torches is a symbol, which was limited to five differences, from one to five torches. Together these two symbols multiply to give five times five equals 25 differences.
example :
without signals : Pigeon post :
this term is used to refer to the use of homing pigeons to carry messages. Pigeons are effective as messengers due to their natural homing abilities. The pigeons are transported to a destination in cages, where they are attached with messages, then the pigeon naturally flies back to its home where the recipient could read the message. They have been used in many places around the world. Pigeons have also been used to great effect in military situations, and are in this case referred to as war pigeons.
Hydraulic and Maritime Semaphores :
Hydraulic and maritime semaphores were available in the 4th and 15th century. Semaphore tools included the use of containers filled with water, a floating rod, and various codes or symbols. In order to make contact with another using the semaphore, an individual would drain the water from the chosen semaphore to a certain height — leaving a coded message based on the height of the water. Semaphores were most popular in Greek history and are no longer of any use in today’s world .
A signal lamp is a semaphore system using a visual signaling device, often utilizing Morse code. In the 19th century, the Royal Navy began using signal lamps. In 1867, then Captain, later Vice Admiral, Philip Howard Colomb for the first time began using dots and dashes from a signal lamp .
Visual Semaphore Is about sending readable signs .
From Sushruta To The Bilateral Cipher :
in a sixth century BC Indian medical text attributed to Sushruta, an ancient Indian sage, as follows. “Given six different spices how many possible different “tastes can you make?” Well, the process of making a mixture can be broken down into six questions. Do you add A, yes or no? Do you add B? C? D? E? And F? Realize this multiplies into a tree of possible answer sequences. Two, times two, times two, times two, times two, times two equals 64. 64 different sequences of answers are therefore possible. Realize that given N yes or no questions, there are two to the power of N possible answer sequences .
In 1605 Francis Bacon clearly explained how this idea could allow one to send all letters of the alphabet using only a single difference. With his bilateral cipher, Bacon wrote famously, “The transposition of two letters by five placings “will be sufficient for 32 differences. “For by this art a way is opened whereby man may “express and signify the intentions of his mind “at any distance of place with objects which are “capable of a two fold difference only.”
This simple idea of using a single difference to communicate the alphabet really took flight in the 17th century due to the invention of the telescope by Lippershey in 1608 and Galileo in 1609. Because quickly the magnification power of the human eye jumped from three to eight to 33 times and beyond. So the observation of a single difference could be made at a much greater distance
Optical Telegraphy:
Telegraphy is used to describe all what we was talking about it before from wiki it means : the long-distance transmission of messages where the sender uses symbolic codes, known to the recipient, rather than a physical exchange of an object bearing the message .
One technology from 1795 perfectly demonstrates the use of a single difference to communicate all things. Lord George Murray’s shutter telegraph was Britain’s reaction to the Bonaparte’s threat to England. It was composed of six rotating shutters which could be oriented as either open or closed. Here each shutter can be thought of as a single difference. With six shutters we have six questions, open or closed? Providing us with two to the power of six, or 64 differences. Enough for all letters, digits, and more. Now realize that each observation of the shutter telegraph can also be thought of as the observation of one of 64 different paths through a decision tree. And with a telescope it was now possible to send letters at an incredible distance between beacons. However, an observation in 1820 lead to a revolutionary technology, which forever changed how far these differences could travel between signalling beacons. This ushered in new ideas which launched us into the information age .
the first thing we can see here is that as the tele communication take a bigger distance the need for an infrastructure to hold the message travling for example the french gouvernment to send a message from paris to lile . they built an infrastructure and a protocol of communication that define the cycle of message sending :
the messsage was able to travel 225 Km in about 10mins :
the main problem in this kind of tele communication tools was in the speed and in the manuel repated tasks to transfer the message from station to an other one . and also the message was clear to all people so if they saw the message multiple times they can know using some kind of algorithms which code book they use to send messages .
The Electrical Telegraph :
An electrical telegraph was a point-to-point text messaging system, used from the 1840s until the late 20th century when it was slowly replaced by other telecommunication systems. At the sending station switches connected a source of current to the telegraph wires. At the receiving station the current activated electromagnets which moved indicators, providing either a visual or audible indication of the text. It was the first electrical telecommunications system and the most widely used of a number of early messaging systems called telegraphs, that were devised to communicate text messages more rapidly than by physical transportation. Prior to the electric telegraph, semaphore systems were used, as the tools we discuess before .
I think that we need to understand the static electricity .
Static Electricity:
Electricity is the set of physical phenomena associated with the presence and motion of matter that has a property of electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by Maxwell’s equations .
Static electricity is an imbalance of electric charges within or on the surface of a material or between materials. The charge remains until it is able to move away by means of an electric current or electrical discharge
all matters are made of atoms . and all atoms contain negativly charged electrons and positivly charged protons and .
In 1774 the idea of the electrical telegraph become real when Alain-René Lesage built the first telegraph using the 26 wires to sent messages .
while each wires represent a letter in the Alphabet . the main problem in this telegraph was in the distance that message can travel . was only able to travel between rooms . in 1775 volta invent the Electrophorus .
An electrophorus or electrophore is a simple manual capacitive electrostatic generator used to produce electrostatic charge via the process of electrostatic induction . with time sientists build more effecient infrastracture to send charger in long distange and more effecient way to generate more powerful discharge .
now we are able to send elecrical charge through wires in a long distance with diffrent frequence . but it still just a signal we need to be able to use those signals .
while using a telegraph . when we press the key for the first time we create a line between us and the reciever . the next time we press we send an electrical enegery this energy attracts a lever lifiting an inked roller on the other end to press against the passing paper strip as long as they key is pressed the elecric circut will be maintained and the roller will press against the paper breaking the cicruit allows the roller to fall away from the paper holding the key down longer periods creates dashes on the paper for shorter periods dots allowing the visual transmission of a morse code signal
The Morse Code :
the morse code was the solution of sending all alphapets in one circuit or line .
Morse code is a method used in telecommunication to encode text characters as standardized sequences of two different signal durations, called dots and dashes, or dits and dahs. Morse code is named after Samuel Morse, one of the inventors of the telegraph
and by automating the task or translation we get this small device that allows us to send messages through wires in a milliseconds .
we gonna contunie our story in the next part .
