For over 25 years we have worked with cable and broadband industry clients around the world in all phases of technology-based projects. We customize our approach based on our client's needs, and can supply expertise for a complete project, or targeted support for specific areas.
The MATLAB® Simulink simulation represents a DOCSIS cable modem transmitting with four bonded upstreams at 16‐QAM, 2560 kSym/sec (3.2 MHz). The cable modem has been modeled against the DOCSIS 3.0 specification, including:
The Volpe Firm is not only an expert on MATLAB modeling, but is also an expert within the telecommunications industry. This means we understand the problems you and your customers are faced with and can then simulate them in a numerical modeling environment. Intelligent design!
Since SIP is a flexible protocol, it is possible to add more features and keep downward interoperability. SIP also does suffer from NAT or firewall restrictions. SIP can be regarded as the enabler protocol for telephony and voice over IP (VoIP) services. The following features of SIP play a major role in the enablement of IP telephony and VoIP:
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.
With recent news headlines reading “A U.S. House Intelligence Committee is launching an investigation against Chinese telecommunication equipment suppliers Huawei and ZTE to find whether the companies pose a security threat to the country“, it is becoming more imperative that we as an industry take a pro-active approach to securing our DOCSIS networks. How does this tie into Capacity Planning? If you build it - They will come to fill it. Theft of service directly impacts capacity planning.
The Volpe Firm are experts in understanding and improving DOCSIS security
The goal of capacity planning is to identify the amount of resources required to meet service demands now and in the future. It is a proactive discipline with far-reaching impact, supporting:
The benefits are wide spread, and the effects are game-changing. This is critical in keeping paying customers online and therefore satisfied.
A passive optical network (PON) is a point-to-multipoint, fiber to the premises network architecture in which unpowered optical splitters are used to enable a single optical fiber to serve multiple premises. A PON consists of an optical line terminal (OLT) at the service provider's central office and a number of optical network units (ONUs) near end users. Ethernet PON (EPON) is a 1 Gbps version of PON that is highly attractive to cable operators and world-wide carriers.
Features are being added to EPON to make it more easily integrated with existing systems. The Volpe Firm are experts EPON technologies and can help you decide how and when to introduce them into your network
Access to superior broadband troubleshooting isn’t as hard to come by as you might think. Several of our clients within the US and internationally have us audit their systems remotely.
How does it work? You send us the files and we analyze them. Upon completion of our analyses we will send you recommendations and advise you of your next steps to address your DOCSIS plants issues. It’s that easy. Get fast results that save you money and increase customer satisfaction.
We are experts in CMTS and cable modem configuration files. We will provide you with CMTS commands that will enable you to create log files and will give us significant insight into the health of your overall physical DOCSIS plant. With this information we help our clients by providing them with strategic and tactical recommendations on how to improve the health of their plant. We are competitively priced and have the technical knowledge of the big players.
Seldom is there a discussion around video, switched digital video (SDV), video-on-demand (VOD) or DOCSIS 3.0 that does not mention the edgeQAM (eQAM) modulator. In the past couple of years, eQAM has rapidly become part of our vocabulary.
Contemporary troubleshooting of Data over Cable Service Interface Specifications (DOCSIS®) requires a combination of RF and IP disciplines. DOCSIS begins at the RF domain where digital signals are modulated and transported across the Hybrid-Fiber Coaxial (HFC) network between two end points. Theses devices consist of a Cable Modem Termination System (CMTS) and cable modem(s). The transmission of digital data forms an IP network, which relies on many common networking devices, such as Dynamic Host Control Protocol (DHCP), Trivial File Transfer Protocol (TFTP), Time of Day (ToD), and Address Resolution Protocol (ARP). Impairments and communications breakdown can and do happen at both the RF and IP domains.
This paper will discuss troubleshooting Voice-over-Internet Protocol (VoIP) in a DOCSIS® (Data-over-Cable System Interface Specification) network. It will begin with the method by which cable operators provide voice services over a data network. This is will start with DOCSIS and VoIP primers in order to provide a common foundation of terminology and understanding of the subject matter.
This paper will investigate the building block of VoIP – the DOCSIS network. In order to obtain the revenue generating opportunities of VoIP, it is essential to understand and troubleshoot a DOCSIS, (Data-Over-Cable Service Interface Specification) network. If all of the elements of the DOCSIS network are working properly, from RF to IP, then VoIP should be elementary, however if there are any RF impairments, DOCSIS protocol impairments, or IP data routing anomalies, then VoIP deployments can be disastrous. Understanding and identifying these impairments will require new technologies and understanding new concepts.
This paper will discuss the most common impairments in a DOCSIS® (Data-over-Cable Service Interface Specification) network and how to identify them. It will begin with the method by which cable operators provide data and voice services over a data network. This will start with DOCSIS and VoIP primers in order to provide a common foundation of terminology and understanding of the subject matter.
Data-Over-Cable System Interface Specification (DOCSIS) is the vehicle for cable operators to obtain immediate revenue-generating opportunities such as broadband data, voice-over IP, IP video-on-demand, and countless emerging IP-based technologies. These growth channels rely on cable operators obtaining and retaining subscribers. Subscriber satisfaction with new services is a direct function of DOCSIS network reliability. Improving DOCSIS network reliability requires new skills and new test equipment, in addition to the skills and test equipment the industry possesses today.
This article provides a working knowledge of DOCSIS networks, the types of impairments that exist in DOCSIS networks, and strategies employed in identifying the impairments in the physical plant.
Data-over-cable System Interface Specification (DOCSIS) is the vehicle for cable operators to obtain immediate revenue generating opportunities such as Broadband Data, Voice over IP, IP Video-on-Demand, and countless emerging IP-based technologies. These growth channels rely on cable operators obtaining and retaining subscribers. Subscriber satisfaction with new services is a direct function of DOCSIS network reliability. Improving DOCSIS network reliability requires new skills and new test equipment, in addition to the skills and test equipment we possess as an industry today.
Once a foundation has been provided, the paper will focus on three (3) high level VoIP impairments, Packet Loss, Delay (also referred to as “Latency” interchangeably), and Jitter. These three components are responsible for nearly all VoIP call degradation, but the underlying manifestation of the components may be the result of a complex number of factors in the distribution network. While some of the impairments can be corrected in the transport mechanisms supporting the VoIP call, some cannot. This leads to the need for advanced techniques of minimizing the effects of packet loss, delay, and jitter. If the impairments cannot be minimized below a certain threshold, the user (hereon referred to as the “caller”) will experience poor voice call quality, analogous to many Public Switched Telephone Network (PSTN) related impairments, such as echo, noisy background, distorted voices, and talker delay. Minimizing these perceived impairments is what will ultimately win or lose the battle for voice services by cable providers.
Contemporary troubleshooting of Data over Cable Service Interface Specifications (DOCSIS®) requires a combination of RF and IP disciplines. DOCSIS begins at the RF domain where digital signals are modulated and transported across the Hybrid-Fiber Coaxial (HFC) network between two end points. Theses devices consist of a Cable Modem Termination System (CMTS) and cable modem(s). The transmission of digital data forms an IP network, which relies on many common networking devices, such as Dynamic Host Control Protocol (DHCP), Trivial File Transfer Protocol (TFTP), and Time of Day (ToD). Impairments and communications breakdown can and do happen at both the RF and IP domains.
All cable modems are pretty simple devices, which mean they are pretty easy to troubleshoot once you understand how they should work. So your subscriber buys a cable modem at their favorite electronics store, (hopefully) registers it with their local cable system, connects the RF coax and plugs in the power. The following steps are what the cable modem should do:
In this article, we are going to closely examine the cable modem registration process, break it down into its fundamental parts, and understand how it should work. We will then look at the registration process as seen from the RF plant using a DOCSIS Protocol Analyzer (DPA). Finally, we will discuss some common non-RF DOCSIS and IP problems that can be readily identified with a DPA