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Chapter 184 Instant Messaging Software

After the website went live, Matthew, Arthur and Pisson told the news to their friends who were in regular contact, and since they were not very popular at school before, most of their friends met on technical BBS. Pen × fun × Pavilion www. ｂｉｑｕｇｅ。 ｉｎｆｏ

However, Matthew and the others still underestimated everyone's sense of expectation for the official BBS of the SAM Association.

At half past twelve in the evening, Lin Hong suddenly found that the tel client prompted that he could not connect to the server.

"Has it been invaded?" This was Lin Hong's first thought.

The message prompted above mainly means that the service is denied due to a large number of connections.

He tried it a few times and found that it was still the case.

At this time, Arthur knocked on his door again, only to be told that he was the same.

There are two possibilities for this situation, one is that someone hacked it, causing the server to refuse service, and the other is that there are too many people really visiting, and the server is overloaded, and it can't afford so many people to visit.

Arthur hurriedly called Matthew to inquire about the situation on his side, and he said that he could access, but very slowly.

After Lin Hong tried a few more times, he finally logged in again, and the content refresh speed was indeed very slow.

Arthur then asked him to log in to the BBS admin and look at the count, which showed that there were more than 1,000 people online at the same time.

The result is very clear, the website is down because there are too many visitors at one time, and the server only has one line, and it can't afford so many people to refresh and visit at the same time for a while, which prompts an error.

They didn't expect it at all, just because they and their friends had promoted their website before, and as a result, it spread ten, ten and hundred, and everyone rushed in.

The SAM team was surprised and delighted by the situation, and Matthew was already considering whether it was necessary to add more lines.

Fortunately, this wave of traffic came and went quickly, and soon BBS resumed normal access, and at this time, there were already many replies and new posts in the forum.

In particular, the tutorial released by Lin Hong has been praised by many people, and many people have said that in response to Lin Hong's call, they began to crack other calculators in their hands that are not of the Texas Instruments brand.

Over the next few days, the SAM group began a slow pace of expansion.

Many people have submitted their work in the forum and would like to join the SAM Association and become a member of this group.

However, Matthew's control over the members is quite strict, and among the dozens of people who meet the standard, only five people are selected, and then the association meeting is held, and everyone discusses these five people, and after eliminating two more people, the SAM association has 7 members.

Considering that there are relatively few people who understand hardware, two of the three newly added are relatively proficient in hardware. And none of the three were members of the Latin School, and one of them was a student at the Massachusetts Institute of Technology.

Lin Hong's work has been greatly lightened by the addition of others, and he has been working on instant messaging software for the past few days.

Last time, he had already noticed that because of the difference in system platforms, it was a bit difficult for him and several other members to communicate, because his computer operating system was Microsoft's DOS, while the other three were all Apple's, and even the hardware architecture was different, not to mention the operating system and application software.

Now that there are new members joining, and they are not from the same school, it is difficult for them to communicate with each other. There is an urgent need for a live chat software that can be cross-platform, and preferably able to support multiple people chatting at the same time.

Lin Hong has been looking for this information these days, mainly through the school map nine astronomy.

He learned that instant messaging software had actually been around since the sixties, first in multi-user operating systems, such as the CTSS (Compatible Time-Sharing) system and the MultiCs (predecessor to UNIX) operating system.

Originally, instant messaging functions were developed as system services, such as the "print" or "e-mail" processes, where information was usually exchanged between ordinary users and system administrators via SMS or notifications.

Later, it began to be used for communication between computers in a local area network. For example, when Lin Hong was in the school computer room for the first time, Arthur hacked into his computer and used such a LAN communication function that comes with the operating system.

After the rise of the Internet, these protocol communication protocols have been understood by more and more technicians, and some instant messaging software has gradually appeared on major mainstream operating systems. These software protocols can be basically divided into two protocol architectures, one is based on point-to-point, that is, the client and the client communicate directly, and the other requires the client and the server to contact, and then the server for intermediate forwarding.

Peer-to-peer communication is relatively simple, just like making a phone call, two people must be online at the same time to make contact, if one party is not very good at the network, or the other party is not online, the communication obviously cannot be carried out. Another point is that peer-to-peer communication can only communicate with one person at a time.

And the architecture of the server and the client, which is similar to BBS, has a dedicated server as a "central hub", and everyone contacts this "central hub", for example, tell him, I want to send a message to so-and-so, please help me forward it. In this way, even if the other party is not online at the time, when the other party is online, the server can send it to him again, which is delayed sending.

In addition, the second architecture has the advantage of being able to have group chats, where one person sends messages to multiple people, making it possible to set up chat rooms.

The communication software called Xaric, which Arthur and Matthew had previously contacted, was built on this architecture.

Lin Hong conducted research specifically on this software and found that the protocol used by this software is the IRC protocol.

Developed in 1988 by the Finnish Yarkou Oikkarin, this protocol is a real-time text messaging protocol over the Internet designed for internal communication between BBSs or group members, allowing peer-to-peer, one-to-many, and even file sharing.

Lin Hong took a look and found that this protocol is public, that is to say, it is free and open to everyone, just like other common TCPIP, UDP, FTP protocols, and can be used at will, whether for commercial use and personal use.

Lin Hong admires it, in the history of the development of science and technology, I don't know how many such people have made contributions, from the very beginning of electronic technology, radio technology, to modern telephone technology, computer technology, it is with the selfless dedication of these technical predecessors, doing the construction of the foundation, can gradually develop to today.

Lin Hong pondered in his heart that after this software was written by himself, it would also be used by everyone for free and contribute his own strength.

Lin Hong went to the school library to look for it before, but he didn't see any information about the IRC protocol, and then he asked Arthur and Matthew, and the two of them didn't know where to find this information.

Later, he had to go to some technical forums to inquire, and finally someone told him the address of a BBS discussion group, Lin Hong logged in to the discussion group, and finally found the email address of the original author, so he tried to send an email to the original author Yaerkou, in which Lin Hong clearly told him that he wanted to write a software based on the IRC protocol and wanted the details of the IRC protocol.

Originally, I had to wait for a while, but I didn't expect to receive a reply from the author in less than half an hour.

Yarkou is very happy that someone has joined the IRC protocol software development, and he will do his best to help others and provide convenience to everyone.

In the email, he sent Lin Hong detailed technical details of the protocol, and also included the latest upgrades, including channel encryption and easier file sharing.

Originally, Lin Hong only wanted to write a communication software for communication within the team, so that only one server side was needed, and the others were connected as a client and a server.

However, after reading the latest IRC protocol in Yarkou, he decided to extend the software functions he had envisioned not only to one server, but several, that is, to integrate both the server and the client side in the software. In other words, each user can use themselves as a relay server to provide services to everyone. In addition, communication between servers can also be carried out.

In fact, this architecture is very similar to amateur radio. In radio communications, there is a special station called "wireless repeater", which can realize the relay and amplification of signals, so as to extend the coverage of radio networks.

In the early days of radio invention, people had not yet discovered the long-distance propagation characteristics of short-wave signals, while medium- and long-wave radio ground-wave communications had limited distances due to earth absorption losses. In the early days, amateur radio amateurs used manual relay to expand the range of communication. The principle is the same as that of relays, and with the enthusiastic help of ham volunteers, hams can send radio signals to the other side of the ocean or even to the other side of the world just by means of long waves

Lin Hong decided to modify the architecture so that each client has the function of "repeater" at the same time, which can greatly enhance the stability of the entire instant messaging system. Because if there is only one server, if that server has a problem for some reason, then communication between other people will not be possible at all.

This is not the case with the redesigned architecture, where if one node is corrupted, the message can still be transmitted to the destination through the other node. Theoretically, there are countless paths for information transmission, as long as the shortest path algorithm is used to find the shortest one.

As for the language of writing this software, Lin Hong finally chose the C language, he took into account the needs of cross-platform at the beginning, and only the C language can meet this requirement among the high-level languages he has been exposed to.

……