DOCSIS Archives

2 05, 2012

Why is QAM Getting Me Down?

Mia Colabrese2021-08-18T09:11:04-04:00May 2nd, 2012|

64-QAM lower than Analog video on the downstream? 64-QAM lower than 16-QAM on the upstream? Why is a 6.4 MHz channel lower than a 3.2 MHz DOCSIS channel? Someone said there is math for all of this, but man QAM is getting me down! These questions come up in every lecture I give on DOCSIS. Why do QAM measurements show up at different levels on a spectrum analyzer than analog measurements. What's more, why do QAM signals of different bandwidth have different levels? Some of the questions have

29 02, 2012

Impact of Impulse Noise on Adaptive Pre-Equalization

Mia Colabrese2021-11-24T09:26:04-05:00February 29th, 2012|

For those of you who have attended my seminars you are familiar with adaptive pre-equalization in cable modems (if not I'll explain it in detail momentarily). Also, if you have done any amount of RF plant troubleshooting you are certainly familiar with Impulse noise (again, I'll cover this too). But if you are like me, I never knew that the two topics were co-related.

27 02, 2012

DOCSIS 3.0 Cable Modem Registration

Mia Colabrese2021-08-17T16:15:14-04:00February 27th, 2012|

This article will discuss the channel bonding process and ultimately the DOCSIS 3.0 cable modem registration process. In order to be able to understand this article, I will make many references to my prior article on Cable Modem Registration which focused on DOCSIS 1.x and 2.0 cable modems.

26 01, 2012

Advanced Troubleshooting in a DOCSIS 3.0 Plant

Mia Colabrese2020-07-02T17:55:04-04:00January 26th, 2012|

If you missed the SCTE Cable-Tec 2011, I am making available my presentation and white paper on Advanced Troubleshooting in a DOCSIS 3.0 Plant. Each speaker had only 20 minutes to cover topics that could easily last hours, so the presentations are understandably brief. Below you will find my presentation in "Slideshare" for online viewing as well as a fully downloadable PowerPoint version. The PowerPoint version also has reader notes attached at the bottom of each slide which you may find useful. In addition, the animations work a little better in the downloadable version.

7 12, 2011

DOCSIS 3.0 Partial Service

Mia Colabrese2021-08-17T10:25:49-04:00December 7th, 2011|

Partial Service is a new term encountered in the DOCSIS 3.0 MULPI specification and realized in field deployments of DOCSIS 3.0 cable modems using upstream bonding. This was a topic that I touched on in this years SCTE Cable-Tec Expo, but will explore in greater detail in this article. Partial service can be considered a feature because the cable modem will stay online even when one or more upstream transmit channels goes offline.

23 11, 2011

Fresh Tech | Intraway Secures DOCSIS

Mia Colabrese2020-07-02T16:34:58-04:00November 23rd, 2011|

I first heard of Intraway's products through a LinkedIn request to talk about DOCSIS security from Intraway's CEO, Leandro Rzezak. This immediately peaked my interest becuase today our DOCSIS networks are inherently insecure and many are unaware of this. What do I mean by insecure? No, not crying and sniffling in a corner. They are open to theft of service, illegal intercept of the data transmitted, illegal wiretapping of phone calls, etc. Even with Baseline Privacy Interface Specification (BPI+) DOCSIS is quite hackable as evidenced on a number of well known hacking sites. The cool factor in the Fraud & Network Usage Control module offered by Intraway is that they have developed effective algorithms which sit on-top of the most used provisioning systems, Cisco's CNR and Incognito's BCC.

22 11, 2011

Fresh Tech | DOCSIS Protocol Analyzer – Can’t stop a good idea!

Mia Colabrese2021-08-18T10:13:29-04:00November 22nd, 2011|

When I first heard rumor that a knew company had a DOCSIS protocol analyzer floating around I had to see it! With full disclosure, many of you know that after 10 years in RF and fiber-optic transport equipment, I spent a few years designing, marketing and selling DOCSIS protocol analyzers. More specifically I focused on making them available to cable operators because I knew they could detect really difficult to isolate problems. Averna know owns the technology from my Sigtek days, so it is nice to see a new competitor in the space. What's more is that its nice to see this competitor at SCTE Cable-Tec Expo who is interested in cable operator's issues.

14 11, 2011

Press Release

Mia Colabrese2011-11-14T07:00:04-05:00November 14th, 2011|

Press Release The Volpe Firm offering solutions, services and products for the broadband telecommunications industry The Volpe Firm gets Seal of Approval from Clients Alpharetta, GA November 14, 2011: The Volpe Firm offers solutions, services and products for the broadband communications industry with a focus in DOCSIS, data, video, and VoIP communications. We provide everything from specialized DOCSIS 3.0 seminars and or tailored DOCSIS training to high level hardware architecture engineering design and system troubleshooting. The Volpe Firm, with 30 years of combined telecommunications experience, specializes in DOCSIS,

11 11, 2011

SCTE Cable Tec Expo – Atlanta 2011

Mia Colabrese2011-11-11T10:30:44-05:00November 11th, 2011|

SCTE Cable Tec Expo - Atlanta [list type="list2"] Advanced Troubleshooting in a DOCSIS 3.0 Plant Mon, November 14 – Thu, November 17 Presentation Workshop is Wednesday, November 16, 8:00am – 9:30am Repeated November 16, 11:00am - 12:00pm [/list]

21 09, 2011

Cable Modems init(r1) init(r2) Why are they stuck?

Mia Colabrese2021-08-20T09:21:27-04:00September 21st, 2011|

Cable Modems init(r1) init(r2), DOCSIS Cable Modems going offline? DOCSIS Cable Modems init(r1) init(r2) are stuck or offline! Many of us have been there before - one or more DOCSIS cable modems init(r1) init(r2) stuck in one of numerous "init()" conditions - how do we interpret these messages and what do we do? A recent reader wrote in and had just this problem. DOCSIS cable modems going offline and getting stuck in "R1" or "R2" condition, or Cable Modems init(r1) init(r2), because these are the status conditions displayed on the DOCSIS CMTS