Mia Colabrese, Author at Volpe Firm

1 07, 2010

DOCSIS 3.0 Tutorial – The EQAM

Mia Colabrese2021-08-17T15:58:05-04:00July 1st, 2010|

In my article on DOCSIS 3.0 M-CMTS architecture, I talked about the distributed nature of the CMTS with an M-CMTS core (the CPU of the system), a DOCSIS Timing Server, and an edge Quadrature Amplitude Modulator (EQAM). I am going to cover the EQAM in detail in this article because in the past couple of years, EQAM (also spelled eQAM) has rapidly become part of our vocabulary but its operation and value often go unappreciated. Further, in order to fully understand DOCSIS 3.0 operation, downstream channel bonding, and possible issue which may arise, a thorough understanding of the eQAM is critical.

26 06, 2010

DOCSIS 3.0 Tutorial – M-CMTS Architecture

Mia Colabrese2021-11-24T09:41:52-05:00June 26th, 2010|

In this article I am going to further explore the M-CMTS in order to describe two import elements of DOCSIS 3.0 network, the edge-Quadrature Amplitude Modulator or EQAM and the DOCSIS Timing Interface Specification Server or DOCSIS Timing Server. Before I cover these components I will show how they are integrated with the M-CMTS architecture.

25 06, 2010

bradyvolpe.com v2.0

Mia Colabrese2020-11-25T09:02:21-05:00June 25th, 2010|

Changes to bradyvolpe.com! Due to traffic utilization and site limitations I have out-stayed the welcome of the free hosting capabilities of my previous site. Not a bad problem to have. On this new site I have the capabilities to add a great bit more content, interactivity, video/audio content and perhaps some feeds from live demos. With this comes overhead so I will be putting in place some Google Adsense advertisements to hopefully offset these costs. In the mean time I will continue to work on completing my DOCSIS

21 06, 2010

DOCSIS 3.0 Tutorial – CMTS Architecture

Mia Colabrese2021-08-18T10:10:11-04:00June 21st, 2010|

Before we dive into bits, bytes and protocol, first we will discus some hardware. During the evolution of DOCSIS 3.0 there were a number of interesting interim steps along the way, shall we say building blocks, to arrive at a full blown D3.0 CMTSs. This left us with two fundamentally different system architectures in production by CMTS vendors, Integrated and Modular CMTSs. It is important to understand these "architectures" from a purchasing, operational and deployment standpoint as they have different requirements in some cases, some are better than others depending on the system layout.

12 10, 2009

DOCSIS 3.0 Tutorial – Introduction

Mia Colabrese2021-08-17T16:05:13-04:00October 12th, 2009|

This is the first of a new series of Tutorials focused on the Data Over Cable Service Interface Specifications (DOCSIS) version 3.0. I will make the assumption that you are familiar with the DOCSIS 1.x / 2.0 standards or have already reviewed my DOCSIS Basics Tutorial as I will be using many terms without explanation since they were previously covered. The DOCSIS 3.0 specification is an extension of the DOCSIS 1.x and 2.0 specification which dramatically increases the data throughput by adding a technology known as channel bonding to the DOCSIS downstream and upstream, adding increased security, adding support for IPv6, and substantially improving the back-office management support (MIBs, SNMP, IPDR, etc.) for DOCSIS. Each of these topics will covered in much greater detail in this DOCSIS 3.0 tutorial in multiple posts yet to come.

7 10, 2009

DOCSIS Upstream – Part II

Mia Colabrese2021-08-17T13:40:53-04:00October 7th, 2009|

This article will focus more specifically on DOCSIS 3.0 issues that will occur as you are deploying DOCSIS 3.0 or post -deployment.

2 10, 2009

Speeding Upstream – Part I

Mia Colabrese2021-08-18T10:19:55-04:00October 2nd, 2009|

The first part of this article (in CT's March 2009 issue) discussed downstream potential issues, while this one focuses on the potential issues associated with upstream deployments. In particular, this article covers the critical upstream areas that one should be aware of when getting ready to deploy or already deploying DOCSIS 3.0.

2 07, 2009

DOCSIS 3.0 Tips

Mia Colabrese2020-07-02T15:51:55-04:00July 2nd, 2009|

If you have not had a chance to catch the June issue of Communications Magazine, check out the article penned by John Downey, of Cisco Systems, and I on "the critical upstream areas that one should be aware of when getting ready to deploy or already deploying DOCSIS 3.0." The shortened version of this article can be found on CT's website HERE. The full version should be made available on this blog soon.

20 04, 2009

DOCSIS and Cable Modems – How it works :: Tutorial Wrap Up

Mia Colabrese2021-08-17T13:35:17-04:00April 20th, 2009|

If you have followed the "DOCSIS and Cable Modems - How it works" tutorials this far, congratulations! You now have a basic foundation of how DOCSIS networks operate and the ability to pick up the DOCSIS specification and read and comprehend it - this is hard to do for the novice. If you are just finding this blog for the first time, then I recommend that you go to the DOCSIS Tutorial Series and start at the beginning before proceeding.

9 03, 2009

DOCSIS and Cable Modems – How it works :: Quality of Service

Mia Colabrese2021-08-17T13:22:59-04:00March 9th, 2009|

DOCSIS 1.0 enabled data over coax with a "best effort" service using a data request-grant methodology. DOCSIS 1.1 and subsequent specifications added guaranteed Quality of Service (QoS) by providing Unsolicited Grant Synchronization (UGS) which means that a cable modem does not have to send a data request in order to receive a bandwidth grant from the CMTS. The new UGS service is an enabling technology which has allowed cable operators to successfully deploy the highly revenue generating Voice-over-IP (VoIP) services. In the following sections I will illustrate the differences between best-effort (request-grant) and QoS (UGS) services.

About Mia Colabrese