DOCSIS 101 Archives

19 07, 2019

T3 & T4 Timeouts Cable Modem Registration – Back to Basics

Mia Colabrese2021-08-15T18:42:34-04:00July 19th, 2019|

Happy Friday Everyone. Today is July 12th and this is episode 49 of Get Your Tech On, our show on All Things DOCSIS. I'm Brady Volpe, Founder of The Volpe Firm and Nimble This. With us is, John Downey, who recently carried a CBR-8 on his back, up Mount Kilimanjaro to ensure broadband service. John is also CMTS Technical Leader at Cisco Systems, welcome John. Todays show: Upstream MER registration explained Cable modem registration T3 and T4 Timeouts In The News: https://www.lightreading.com/cable/ccap-next-gen-nets/comcast-commits-millions-to-harmonics-cableos-platform/d/d-id/752671 Comcast Commits Millions to Harmonic's

24 06, 2019

Low Latency and Virtualization

Mia Colabrese2021-08-15T18:44:51-04:00June 24th, 2019|

Happy Friday Everyone. Today is June 14th and this is episode 48 of Get Your Tech On, our show on All Things DOCSIS. I'm Brady Volpe, Founder of The Volpe Firm and Nimble This. With us is, John Downey. John is also CMTS Technical Leader at Cisco Systems, welcome John. AQM (active que management) Mini slot proactive grant service OFDMA John thank you for your time today. This was a great episode. Our next Episode 49 is scheduled in July 12. We do our best to bring our

10 09, 2018

Optimizing the DOCSIS Upstream

Mia Colabrese2018-09-10T08:37:20-04:00September 10th, 2018|

Data-Over-Cable Service Interface Specifications (DOCSIS) version 3.1 offers a host of exciting possibilities and realities for cable operators. I have covered many of these topics in previous articles but the one thing that cannot be overlooked is the basics. It doesn’t matter how great these new technologies are if you do not pay attention to the foundation. It’s not any different than a house. If your foundation isn’t solid who cares if you have the best theater system in it. It can crumble under foot if the foundation

2 09, 2016

How DOCSIS Revolutionized the Cable Industry

Mia Colabrese2024-11-21T13:32:09-05:00September 2nd, 2016|

How DOCSIS Revolutionized the Cable Industry The cable industry is constantly facing competitive threats from companies like Google and Verizon who up the data speed game with fiber optic cable. They compete by offering higher and higher data speeds at lower and lower prices. But before we get into that, let’s look back at the 20 years of DOCSIS history and how DOCSIS has revolutionized the cable industry. Google Fiber Expansion (Source: Google.com) 20 Years Ago - The Internet Emerges The year was 1996. Broadband Library was celebrating

8 08, 2016

Top Reasons Cable Modems are not Getting Expected Speed and CMTS Monitoring

Mia Colabrese2021-08-16T20:05:30-04:00August 8th, 2016|

Cable Modems not Getting Speed - Top Reasons Cable Modems are not Getting Expected Speed and CMTS Monitoring Episode 22 Hosted by Brady Volpe of the Volpe Firm, Nimble This and Guest John Downey, CMTS Technical Leader at Cisco Systems. Today’s show we will cover cable modems not getting speed and monitoring your CMTS for proper Cable Modem State and Service Flow Operation. At the bottom John has supplied us with his presentation if you would like to listen along with viewing the slides. There were some technically issues

20 04, 2016

RF Measurements in the Cable Plant

Mia Colabrese2021-08-16T20:15:37-04:00April 20th, 2016|

RF Measurements in the Cable Plant - Learn more about RF Episode 20 Hosted by Brady Volpe of the Volpe Firm and Nimble This. Guest John Downey, CMTS Technical Leader at Cisco Systems and special guest, Ron Hranac Technical Leader at Cisco Systems. Today’s show we will cover a number of topics including RF measurements and fundamentals. The discussion starts with basic building blocks of the sine wave and evolves to how QAM (quadrature amplitude modulation) signals are comprised of sine waves with varying amplitude and phase shifts, which means even though we call

10 03, 2013

DOCSIS Reed-Solomon Codewords

Mia Colabrese2013-03-10T20:01:38-04:00March 10th, 2013|

How many bytes can a Reed-Solomon codeword bite? In my previous article on DOCSIS Codeword Errors, reader "Sandy" asked how many Reed-Solomon codewords would be required to transport a 1518 byte length of data? This is a very good question and one that I had never considered until I first faced when designing DOCSIS data-layer models in MATLAB. In the example I used in my previous article I chose a word that was 16 bytes long. I did this because it made it easy to draw an 8x8

1 10, 2012

Cable Modem Registration | A Second Look

Mia Colabrese2021-08-17T10:17:11-04:00October 1st, 2012|

DOCSIS Cable Modems Registration Process Even the most interesting man in the world enjoy's the DOCSIS cable modem registration process, so it is worth a second look. It is one of the most popular topics because it covers a wide range of how DOCSIS works, from physical layer to Internet protocol (IP) layer. It is therefore worthy of an encore article with more depth and an update to include DOCSIS 3.0. During the cable modem registration process it is important to understand that three (3) different levels of

20 08, 2012

DOCSIS Security | Mac Address Cloning

Mia Colabrese2021-08-18T10:07:01-04:00August 20th, 2012|

Theft of Service via Cloning DOCSIS Security - If only cloning your favorite pet was as easy as cloning a MAC address on a cable modem. There are dozens of websites out there giving subscribers or hackers step by step instructions on how to clone a MAC address. Each cable modem, regardless of brand, is uniquely identified by its Cable Modems ID, or MAC address - short for Media Access Control. This address is programmed into a writable memory address of the hardware in the cable modem, and is associated with a

14 08, 2012

DOCSIS Security | Uncapping Cable Modems

Mia Colabrese2012-08-14T10:57:21-04:00August 14th, 2012|

So what is uncapping cable modems? Uncapping cable modems refers to activities performed to alter a DOCSIS cable modems settings. Plain and simple someone is messing with the cable modem's configuration file to get what they want. So what do they want? Greater bandwidth (the need for speed), wanting more than one public IP, or any other configurable options a DOCSIS modem can offer. Maybe they just want to prove they can do it and or feel they are getting the shaft from their cable provider. Really the psychology of people is