Multimedia Cable Network System Research Articles

The effects of standardization process on competition: An event study of the standardization process in the US cable modem market

This paper assesses the effect of standardization on competition in the US cable modem market. The standardization process in this market has involved two competing standardization groups, a commercial consortium (Multimedia Cable Network System Partners Ltd) and an official organization (the Institute of Electrical and Electronics Engineers working group IEEE 802.14). In such circumstances, standardization related activities might affect competition both within a standardization group and between standards. The paper distinguishes between these effects based on firms’ membership in standardization groups, and uses event study methodology to assess the effects of standardization activities on competition as perceived by investors. The results imply that not all consortium-led standardization activities were perceived to increase inter-firm competition.

An adaptive fast expansion, loading statistics with dynamic swapping algorithm to support real time services over CATV networks

As the community antenna television (CATV) networks becomes ubiquitous, instead of constructing an entirely new broadband network infrastructure, it has emerged as one of the rapid and economic technologies to interconnecting heterogeneous network to provide broadband access to subscribers. How to support ubiquitous real-time multimedia applications, especially in a heavy traffic environment, becomes a critical issue in modern CATV networks. In this paper, we propose a time guaranteed and efficient upstream minislots allocation algorithm for supporting quality-of-service (QoS) traffic over data over cable service interface specification (DOCSIS) CATV networks to fulfill the needs of realtime interactive services, such as video telephony, video on demand (VOD), distance learning, and so on. The proposed adaptive fast expansion algorithm and the loading statistics with dynamic swapping algorithm have been shown to perform better than that of the multimedia cable network system (MCNS) DOCSIS.

A novel mechanism for providing service differentiation over CATV network

With the emersion of new types of applications on the Internet, the need of broadband access is unavoidable. It also makes the differentiation of services provided by the network necessary. One of the most competitive broadband access solutions is Cable TV network since it is a network now in widespread use with enough bandwidth. Among the protocols of digital data-over-cable, Multimedia Cable Network System (MCNS) Data-Over-Cable Service Interface Specifications (DOCSIS) is the most popular standard nowadays. Based on this standard, we proposed a novel mechanism that can provide service differentiation over cable network. We explain the detail operation and interaction of each part of the system in this paper. Simulation is used to find out the performance on two subjects. First, MAC protocol configurations and parameters are discussed. Second, we compare various scheduling methods for providing service differentiation in the headend. From the results, the proposed mechanism is applicable and the characteristics of key parameters are found.

Performance evaluation of candidate MAC protocols for LMCS/LMDS networks

Broadband wireless access (BWA) offers attractive features such as ease and speed of deployment, fast realization of revenues, and low infrastructure cost. This paper focuses on medium access control (MAC) alternatives that can find application in an LMDS/LMCS network capable of supporting multimedia traffic. Multifrequency demand assignment TDMA-based schemes appear (at the moment) to be a suitable choice in this context. The selected protocol should be dynamically capable of providing multirate capabilities and quality-of-service guarantees. An obvious candidate for the aforementioned purpose is the LMDS-specific MAC proposal in the DAVIC 1.2 recommendation. For purposes of comparison, we also examine the evolving IEEE 802.14 MAC convergence protocol and MCNS (multimedia cable network system) DOCSIS (ITU J-112) MAC standard that are intended to support similar applications and services in an HFC (hybrid fiber coax) environment. The three protocols are examined under noiseless and noisy channel conditions. Previous results on LMDS channel characteristics are summarized and used for modeling noisy channel conditions. The candidate protocols are compared in terms of mean access delay, throughput, and collision multiplicity statistics, when contention of users is involved. The effect of dynamic slot allocation on the performance of the candidate protocols is also examined.

Allocation and scheduling algorithms for IEEE 802.14 and MCNS in hybrid fiber coaxial networks

IEEE 802.14 and MCNS (multimedia cable network system) are two standards developed for the hybrid fiber coaxial (HFC) CATV networks. Both standards model an upstream channel as a stream of minislots. But their philosophies on resolving collisions in the shared upstream channel are rather different, where IEEE 802.14 adopts the priority+FIFO first-transmission rule and the n-ary tree retransmission rule, and MCNS adopts the binary exponential backoff algorithm with adjustable window sizes. Both provide reservation access, while IEEE 802.14 and MCNS also support isochronous access and immediate access, respectively. In this paper, we try to prepare a suggestion list for vendors on how to allocate minislots for reservation access and immediate access and how to schedule the reserved bandwidth, which greatly affect the performance of a cable network and are left open by the standards.

Erroneous MPEG packet synchronization in the MCNS/SCTE/ITU-T J.83 Annex B standard

This paper presents a phenomenon with repeating data packets sent according to the MCNS (multimedia cable network system) DOCSIS (data over cable service interface specification)/SCTE (Society of Cable Telecommunication Engineers)/ITU-T 5.83 Annex B standard. When repeating packets are received by a receiver, the receiver may erroneously lock onto the bit stream and produces incorrect MPEG packets. Repeating packets are usually not generated in practical systems. They are, however, easy to generate and preferred in a testing environment during product development. A system vendor may unknowingly encounter this phenomenon and incur delays in product designs in trying to solve this apparent error. This paper presents the mathematical background on the cause of this phenomenon.