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Thanks to the late night inspiration of engineer Venk Mutalik, CastMast has discovered how to break its fiber optic cables in its network in 90 seconds.

It enables the company to send repair crews for immediate fiber breakage, and it protects the company against its biggest enemy: construction workers, equipped with backhoes, carrying accidentally buried cables.

It is important at a time of epidemic when broadband connectivity is important for everyone. Fast fixing cables will become even more important as networks hold 10 times more data in the coming years, as Comcast eventually upgrades to 10G, where it can deliver 10 gigabytes of up to 20 million subscriber homes upstream and downstream. Its network.

“We’ve been constantly focused on connectivity, because it’s never been more important,” Elad Nafshi, senior vice president of the Next Generation Access team, said in an interview with VentureBit. “COVID really highlighted the importance of connectivity. And we’re constantly evolving our network. We see our network as the smartest, fastest and most reliable. But you can always do better. “

Mutalik is an engineer on the Next Generation Access Access team, and Comcast has taken the idea and implemented it on its network in a way that keeps the network running smoothly. Mutalik found a way to recreate previous pay generation technology to monitor Internet traffic. Comcast can now easily send light signals through a fiber optic network. The light beam hits their destination and bounces back. Engineers measure how long it takes to do if the network is normal. But if there is a break in the line the light returns more quickly, and uses the time difference to calculate the exact distance of the break and where the time is.

On top of that, they use the same tests to find out if fiber lines are struggling or lose their ability to transfer information. This gives the company an understanding of the data traffic on its networks, but not the actual data that we are sending to each other in messages and such messages, ”Nafshi said.

How the network works

Comcast has shown that it can achieve 4 Gbps full duplex internet speeds.

Above: Comcast has shown that it can achieve 4 Gbps full-duplex internet speeds.

Image Credit: Com Com

Long-distance fiber-optic network devices connecting cities and towns in the United States rely on thousands of high-end devices called “RAADM” (reconfigured-d-drop multiplexers) that ensure trillions of bytes of information reach their intended locations. ROADMs have “optical spectrum analyzer” chips that are essentially ultra-smart prisms, splitting fiber optic laser lights into smaller and smaller beams and reliably pointing them to the right places, all in milliseconds.

Every year or so, manufacturers release a new generation of more powerful and high-resolution optical spectrum analyzer chips, and network tors operators replace previous versions of devices in their network. The same is true for other components such as the optical time domain reflector, the ical optical sonar that uses “ical optical echoes” to indicate fiber imperfections.

Mutalik’s solutions

A lot of cables have been laid in Comcast.

Above: Comcom has been laying a lot of cables.

Image Credit: Com Com

Got the same reciprocal thinking. He knew that previous generation optical spectrum analyzers and other such components were powerful devices designed to handle fiber-optic traffic over thousands of miles. What would happen if Comcast reintroduced these mature to electronic chips to monitor thousands of feet of travel traffic?

“We will increase our fiber wealth 10 times, or something will grow faster depending on the time, because all we have to do is connect through fiber,” Mutalik said. “And so we have a huge amount of fiber assets that go to the coast. There are a quarter of a million nodes that we have attached to the headends and they are all short distances. The question was, ‘Do we know what all those fibers do?’

He added, “We know what the wavelength is on those fibers. How much wavelength is going down? How many wavelengths are coming? And if there was some kind of outage, how do we know that the outage is the opposite of a fiber card that hits a telephone pole and then knocks out the node? ‘

ComComcast’s local fiber-optic networks in cities, towns and neighborhoods cover shorter distances than long-distance networks connecting cities. Mutalik argued that optical components, such as optical spectrum analyzers, designed for pinpoint measurements over thousands of miles, would be more effective in operating an optical network that powers a neighborhood.

Specific problems

Comcom's network

Above: Comcast’s network makes Gigabyte Internet available to 59 million homes.

Mutalik’s team got together and built a prototype of a system called XMF. By installing these optical spectrum analyzers in the local fiber network and developing software to leverage the capabilities of the devices in a new way, the team was able to achieve unprecedented visibility in the operation of every millimeter of those networks.

“The insight was that if you go back and look at the back edge of the technol edge g, you see that we have three optimally faster and more excellent resolution optical spectrum analyzers. But older pay generation chips are available and it is perfectly fine for us to take what was in the signal path and move it to the monitoring path, ”Mutalik said. “And they don’t go through the signaling. We’ve created these new test points on our network where light can automatically, broadly, observe, because the signals don’t affect the path.”

Mutalik added, “And then we have optical spectrum analyzers and the time domain reflector sends a pulse of light and then we wait for the echo. And then based on the signal process of the echo, we can determine how long the light travels before being reflected and returned. “

XMF takes advantage of previous pay generation technology for new purposes, making it significantly more visible to technical teams, making it more cost effective to install ultra-precision fiber diagnostic tools at multiple points in the local fiber network.

The XMF platform constantly monitors thousands of local broadband optical links every minute on the Macast network, measuring both the optical spectrum and testing the length and quality of fiber links. Practically, this means that with XMF installed, network engineers can now pinpoint the location at which the local fiber network is experiencing a problem and can share specific geography with local technologies.

Comcast can now find the exact moment when the fiber is cut. Then it can be compatible with things that happen, such as construction or bad weather or something else. It is important to know whether it is a fiber cut or a power outage or a defect.

“Diagnosis is very difficult because they require different actions from technical people,” Mutalik said. “If it’s a fiber cut, you have to go to an optical technician. If there is a defect in the node, you have radio frequency (RF) technology. Sometimes you need hours to triangle and find out what happened. “

And the result is downtime for subscribers.

When installed, XMF reduces the time taken to detect the technology and separates the fiber cut from two hours to two minutes. It helps the company get customers back online quickly. It is also used to detect and improve degraded fiber performance before instructing customers. They use machine learning to see how links degrade over time and how maintenance can keep the network going.

Nafshi said, “This is a wonderful example of Commast innovation, and when you take a step back, the visibility of what’s going on in the network never mattered. How do we get the same level of visibility from a network? And that’s really the challenge that led Venk to look at the thousands of miles of fiber representing our access network. “

Rolling it

Comcast Technician

Above: Comcast Technician

Image Credit: Com Com

The XMF team is now rolling out a handheld version of the XMF platform that technicians can use to identify fiber link issues in the specialist field in seconds and also diagnose and correct those issues on the spot. And as the team works to improve the handheld platform, they’re starting to scale the rack-mounted original version more broadly on a broader MacArthur network.

This is an important step towards 10G as the industry accelerates momentum and capacity, but it will also be important to continue to increase credibility, ”Nafshi said. Technologies such as XMF and Comcast Max Octave have helped ensure that as the network reaches new heights of speed and capacity, it will also be more secure and reliable for its dependent customers.

“The investment we are making in Technolog in G and the progress towards 10G, we are not just adding more momentum,” he said. “We have also hit key milestones in the last 12 months. Last year, at the height of the epidemic, we announced that 1.25 gigabits per second symmetrical services, a trial on our distributed access network. In April, we announced the first lab trial of the DOCSIS 4.0 FDX, where we can add 4 gigabytes of symmetrical services per second. So a ton of network innovation goes into future-proofing our network. “

In the meantime, Comcast must take care of the network. Nafshi said earlier this week that a truck in Houston hit a telephone pole, and it pulled out 75 knots of fiber from one pole. The system kicked and fixed the cut location at a distance of about five kilometers from the hub site. A team was immediately dispatched and they restored the service and cut out the length of the outage.

The company seeks to communicate with construction teams using backhoses to reduce the risk of fiber cuts. But the stuff happens. In London, a crew filled a hole and hit a fiberglass spine and took down part of London’s Internet of Access for three days. I don’t know about you. But if my internet was down for three days, I would go to a hotel.


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