What exactly is the Internet?
It is technology, the underlying logic of the information age.
But in Lin Lixin's view, the most important point is that it connects people together.
What was that saying again?
In the past, travel was slow, and letters took a long time to arrive.
Honestly, for Lin Lixin, a modern person, what bothered him most about coming to the 1980s and 90s was not the limited hardware capabilities.
Different hardware environments often give rise to many interesting works.
Take Metal Gear Solid as an example.
If it weren't for the MSX's extremely limited capabilities, Kojima originally intended it to be a real-time combat game with a fast-paced, action-packed gameplay style.
Limited by hardware capabilities, this led to the creation of Metal Gear Solid, a game that became an instant hit thanks to its stealth gameplay.
Hardware limitations have two sides to a game.
Simply focusing on hardware capabilities and game scale often breeds complacency among developers, making them unwilling to consider solutions and only concerned with piling on features. What truly distressed Lin Lixin was that the internet had regressed to a primitive state in one fell swoop.
The distance between people suddenly seemed to stretch out to a great, great distance.
The only media for obtaining information were magazines, television, and radio.
Stories passed down by word of mouth sometimes take years to reach the other side of the world.
This was also his original intention in establishing the Nexus company.
Just like its name suggests, Lin Lixin wants to reconnect humanity.
Email is the first step.
As it turns out, free email is an absolute huge temptation for people in this era.
With its ubiquitous slogan, "[get your free email at novamail]", novamail's expansion speed far exceeded everyone's expectations.
Even Lin Lixin himself was somewhat caught off guard.
These days, Nexus has been expanding its capacity almost non-stop.
The initial estimate of "several hundred million dollars in expenditure" now seems far too conservative. Given the current situation, several hundred million dollars is unlikely.
He needs to accelerate the development of the Internet as soon as possible.
micronova.
As Gamenova's largest research institute and semiconductor business, this place has been the birthplace of many key technologies.
Lin Lixin's trip here is intended to further expand his investment in this sea of patents.
There is a crucial technology that we should have discovered eight hundred years ago.
Now that Nexus is gaining even more popularity thanks to its free email service, it seems like it's time to give it a shot.
Inside the office.
Vivian huffed and puffed as she tossed a large bundle of cables in front of Lin Lixin.
"Phew—thank goodness I've practiced."
She wiped the sweat from her brow, gestured towards Lin Lixin with her chin, and said, "Here you go, what you wanted."
This is a huge bundle... of telephone wire.
Vivian picked up a piece of thread and looked at the exposed end of the thread on her head.
"Are you planning to develop dedicated network cables? If so, Nexus's current budget will have to be increased significantly."
As Nexus has developed, it has gradually expanded its network to almost the entire country through pilot programs in various regions.
Only overseas territories like Alaska and Hawaii simply don't have the conditions to be established there.
But here's the problem.
This level of efficiency is not solely due to Nexus's efforts.
Telephone companies and state government departments have also invested significant human and material resources.
By this point in time, the interconnections between various commercial ISPs have long since merged with Nexus.
The once aloof and exclusive academic and research networks on ARPANET have all surrendered and joined the network protocol.
It seems that Lin Lixin's goal of achieving nationwide internet access has been largely achieved. However, a very awkward problem remains.
slow!
Although Nexus's network is the best among several manufacturers, it still cannot change its inherently slow nature.
Ultimately, it's just a dedicated line taken off the telephone network.
Vivian naturally assumed that Lin Lixin was planning to develop specialized network cables after hearing that he intended to acquire a batch of telephone lines for scientific research.
But even if it were to be successfully implemented, the installation costs would be astronomical.
It could even cost more than maintaining email systems and semiconductors now.
Infrastructure construction is incredibly expensive.
"New cables? We haven't even figured out how to use telephone lines yet, why would we need new cables?"
"Ha?"
Vivian looked at the twisted copper wires inside the bundle of thin thread, somewhat puzzled.
The two wires, one red and one green, were twisted into a spiral shape inside the cable. This wasn't an unnecessary addition by the telephone company; rather, it was a solution developed by engineers over many years.
In the past, telephone companies have tried to run the wires straight through the cable.
However, it was later discovered that if this was done, the two parallel lines would be very susceptible to external electromagnetic noise interference.
By twisting them together to form a twisted pair, these noises can be directly canceled out, greatly improving signal quality.
However, current twisted-pair copper wires can only handle signals up to 3400Hz.
In the telephone era, this was more than enough.
However, when faced with the information-packed monster that is the Internet, 3400Hz is practically a water gun, not even a proper water pipe.
This is also the most serious problem currently facing all network providers.
In Vivian's view, there is actually a very simple solution to this problem, but no one wants to do it.
That means upgrading the cable and adding more strands.
If a single twisted-pair cable only has this much capacity, what about two? Four? Or even more?
With increased concurrency comes higher traffic. However, the exorbitant maintenance costs hidden behind this are enough to deter any company.
That's a cost starting at several hundred billion dollars.
Even Gamenova can't withstand this kind of burning.
Even those publicly listed cash behemoths won't easily drag themselves into this quagmire.
"What do you mean you haven't figured out how to use telephone lines? Do you have a way to transmit more information at 3400Hz? A new data structure or expression method?"
"Hey, why are you being so cooperative this time? See, you can be a good straight man too."
Seeing her puzzled expression, Lin Lixin nodded in satisfaction.
Seeing the veins bulging on Vivian's forehead, Lin Lixin laughed and, no longer keeping her in suspense, explained:
"That day, while I was working on a project at Nexus, I was bored and tested something. Guess what I found?"
Lin Lixin cut a section of telephone line and connected it to a signal generator and an oscilloscope.
Then he quietly looked at Vivian.
"... What did you discover?" "Hehe..."
Lin Lixin smiled mysteriously and began to try to get the signal generator to output a signal.
First, it's 1000Hz.
The oscilloscope faithfully output the complete signal.
Texas Instruments, a reliable and long-established brand, has been a frequent supplier of equipment to Gamenova.
He then increased the signal to 3000 Hz.
Apart from a very slight, almost imperceptible voltage drop, there are still no problems.
Vivian stared at the oscilloscope results, wondering what Lin Lixin was trying to say.
It's common knowledge that telephone lines can carry 3400Hz.
Because telephone signals are mostly on this frequency band.
"Don't rush..."
Lin Lixin waved his hand and adjusted the signal generator again. This time, the parameters were directly and suddenly increased to 10kHz, more than tripling.
Can...
Vivian stared at the results on the oscilloscope, her eyes widening slightly.
The voltage dropped slightly by about 0.01 volts, but everything else was normal.
The signal was transmitted completely.
"So that's how it is..."
Before she could finish speaking, Lin Lixin adjusted his words again.
This time, the frequency was directly increased to 100kHz, a full tenfold increase.
The voltage dropped again, but the signal was still delivered.
Next is 500 kHz.
Lin Lixin didn't stop until 1MHz.
Despite the severe voltage attenuation, the signal still reached its destination. A simple calculation of the signal-to-noise ratio revealed surprisingly excellent performance across the entire frequency band.
Although the signal-to-noise ratio begins to degrade significantly above 500kHz, it is still usable and not particularly dirty.
At this moment, Vivian's eyes changed completely.
The playful banter between them was completely shattered at this moment.
This was completely different from the feeling she had when Lin Lixin presented those excellent chip architecture designs that shocked her.
Those things just show that Lin has a lot of ingenious ideas in his head.
But what we're seeing now is a completely different story.
He discovered a gold mine.
A gold mine that has always been right in front of everyone, yet has been ignored by everyone.
Vivian picked up a telephone wire with trembling hands, staring at the twisted copper wires inside, her heart pounding wildly.
How could the physical properties of copper wire be limited to only 3400Hz?
This is simply a choice made by telephone companies to save resources. Modulating the human voice frequency to 300Hz~3400Hz makes it easier for the telephone lines to transmit the signal.
However, the carrying capacity of a pair of ordinary copper wires is far more than that.
"Wait, no, you almost fooled me."
Vivian shook her head, then suddenly came to her senses.
"This result is possible because the line is very short; if it were extended to the Eri level, severe noise would render the data completely unusable."
Bell Company discovered this decades ago.
Choosing 3400Hz not only saves resources but also helps to eliminate noise.
"Yes, that's how it is."
Lin Lixin nodded noncommittally.
"So Carmack and I spent a few days working on it and came up with... well... a hardware and software combined solution."
He picked up a piece of draft paper and drew a line segment on it, with one end at 0 Hz and the other at 1 MHz.
Then another segment was cut off at 3.4kHz. With this cut, the waste of telephone line carrying capacity becomes extremely obvious, with 90% of the frequency band completely blank.
Lin Lixin placed the tip of his pen at the end of the line segment, at 1 MHz.
"We don't transmit all the data on the fastest frequency band, but instead..."
As he spoke, he frantically cut the entire blank space into dozens of independent line segments.
"Break them down into dozens or even hundreds of channels, with each frequency band carrying a different number of bits."
"At the same time, I found that the vast majority of users' needs involve downloading far more than uploading. We can capitalize on this by allocating bandwidth in an asymmetrical proportion, dedicating the majority of it to downloading."
"I call this technology -- DMT, Discrete Multitone Modulation Technology."
"Based on Shannon's Shannon's Theorem, we can substitute the formula and do a simple calculation."
"... In DMT and ADSL environments, we can obtain... bandwidth of several Mbps."
A hundredfold increase!
Moreover... there's no need to rebuild any existing infrastructure.
It can be easily replaced using the existing telephone network. Even after switching to a higher frequency, internet access will not interrupt the call at all.
You can connect to the internet and make phone calls simultaneously!