Introduction This document answers frequently asked questions about Data-over-Cable Service Interface Specifications (DOCSIS) 2.0. Competition among products gives vendor manufacturers incentive to develop cost effective, high quality products. Likewise, competition among standards gives the developer of a standard the incentive to ensure that they are reasonable and provide more benefit than they cost. Cable Television Laboratories, Inc. Motorola's next generation SURFboard SB5100 Cable. Modem incorporates the latest DOCSIS 2.0 Advanced. To 100 times faster than 28.8k analog. Motorola Sb5100 Cable Modem Specs Hours Thanksgiving( ) is a consortium that governs the DOCSIS standard and ensures interoperability, competition, and quality. Cable Labs is dedicated to help cable operators integrate new telecommunications technologies into their business objectives. Parking game download for 5233 46 and 2. It might be inevitable that there will be multiple standards that cover the same business objective. Therefore, with regards to the deployment of DOCSIS 2.0, two specifications have emerged: Advanced Time Division Multiplex Access (ATDMA) and Synchronous Code Division Multiple Access (SCDMA). CableLabs has mandated that, for a cable product to be fully DOCSIS 2.0 compliant, it must support both competing protocols. Motorola Surfboard Sb5100 Cable ModemThere have been several discussions about migration to DOCSIS 2.0 and about which protocol (ATDMA or SCDMA) is the best fit for any one particular business model. Based on recent surveys, some providers are still very unsure about the migration to DOCSIS 2.0. This document addresses some initial concerns of those who are considering DOCSIS 2.0 migration and answers some of the questions that they might have. What is the difference between ATDMA and SCDMA? ATDMA is a direct evolution of DOCSIS 1.x physical layer (PHY), which uses TDMA multiplexing. DOCSIS 1.x upstream PHY uses a frequency division multiple access (FDMA)/TDMA burst multiplexing technique. FDMA accommodates simultaneous operation of multiple radio frequency (RF) channels on different frequencies. Learn about the hardware features and specs of the Motorola SB5102 Internet modem. The Motorola SB5102 modem provides high-speed access to the Internet and other online services. Motorola Inc, 101 Tournament Drive, Horsham, PA 19044, 1-215-323-1000, declares that the SURFboard® SB5101 DOCSIS® 2.0 Cable Modem complies with 47 CFR Parts 2 and 15 of the FCC rules as a Class B digital device. INDUSTRY CANADA (IC) STATEMENT This Class B digital apparatus complies with Canadian ICES-003. So the SB5100 can get the 8 I pay for but at other times it really craps out. SB5100 Spec Sheet >> »broadband.motorola.com/c heet.pdf. My answer is yes an SB5100 is still a viable option, in most cases a cable modem. SpeedGuide.net Broadband Community > Usenet Newsgroups > comp.dcom.modems.cable > Comcast / Motorola sb5100 cable modem dropping. At a glance you seem to be riding on the end of the power level specs. Here are suggested working ranges for solid operation. Sometimes staying off for hours at a time. I called the cable service dept and was. Motorola Sb5100 Cable Modem Specs Hours On 4thTDMA allows multiple cable modems to share the same individual RF channel, because it allocates each cable modem its own time slot in which to transmit. TDMA is carried over in DOCSIS 2.0, with numerous enhancements. SCDMA is a different approach, in which up to 128 symbols are transmitted simultaneously via 128 orthogonal codes. SCDMA multiplexing allows multiple modems to transmit in the same time slot. Both ATDMA and SCDMA provide the same maximum data throughput, although one might perform better than the other under specific operating conditions. Does DOCSIS 2.0 have less rigid upstream performance requirements? The upstream performance requirements in the DOCSIS 2.0 Radio Frequency Interface Specification are not less rigid than the requirements in DOCSIS 1.0 or 1.1. For maximum reliability and data throughput, cable operators still need to ensure that their networks comply with the recommended downstream and upstream radio frequency (RF) parameters in the DOCSIS Radio Frequency Interface Specification. The confusion about this arises from the fact that DOCSIS 2.0 provides for increased upstream throughput—up to a raw data rate of 30.72 Mbps. This is accomplished through the use of higher-order modulation formats, such as 64-QAM. In order for 64-QAM to work in the harsh upstream environment, either the upstream RF performance must be significantly improved, or the data transmission robustness must be improved. Motorola Sb5100 Cable Modem Specs HoursDOCSIS 2.0 includes provisions for improved data transmission robustness from several areas: • DOCSIS 2.0 supports a symbol (T)-spaced adaptive equalizer structure with 24 taps, compared to 8 taps in DOCSIS 1.x. This allows operation in the presence of more severe multipath and microreflections, and should accommodate operation near band edges where group delay is usually a problem. • Some cable modem termination system (CMTS) chipset vendors have developed robustness-enhancing features through improved burst acquisition. Carrier and timing lock, power estimates, equalizer training, and constellation phase lock are all done simultaneously. This allows for shorter preambles and reduces implementation loss. • Forward error correction (FEC) has been improved. DOCSIS 1.x provides for the correction of 10 errored bytes per Reed Solomon block (T=10) with no interleaving, while DOCSIS 2.0 allows correction of 16 bytes per Reed Solomon block (T=16) with programmable interleaving. • While not specifically a requirement of DOCSIS 2.0, many advanced physical layer (PHY) silicon vendors have incorporated some form of ingress cancellation technology into their upstream receiver chips, which further enhances upstream data transmission robustness. Ingress cancellation is a way to digitally remove in-channel ingress, common path distortion, and certain types of impulse noise. Is SCDMA better for impulse noise environments while ATDMA is better for ingress? SCDMA has a Burst Noise Advantage over ATDMA, because of its capability to spread transmissions out over time. Multiple codewords are sent simultaneously, which effectively interleaves codewords from different cable modems. You must accept the Java ME SDK 3.0.5 License Agreement to download this software. Java ME Platform SDK contains an optimized CLDC/MIDP stack. This page contains download instructions for the latest Java ME Software Development Kit. For questions and issues, please visit Java ME SDK Discussion. Download java sdk windows. WTK 2.5.2 has been integrated into Java ME SDK 3.0. While you are welcome to use WTK 2.5.2, we highly recommend the newer feature-rich Java ME SDK 3.0. ORACLE JAVA ME SDK DOWNLOAD. This page contains download instructions for the latest Java ME Software Development Kit. For questions and issues,. However, SCDMA uses longer symbol times than ATDMA, and this reduces the number of errored symbols created for a given forward error correction (FEC) block. This allows those errored symbols to be corrected with the FEC information. Free download buku komputer sd. However, these limitations for SCDMA modems must be considered in the real world: • Must perform periodic ranging for all modems every second. • Only gives throughput benefit when more than 60 percent of upstream traffic is carried in SCDMA mode. • Significant interoperability issues remain in SCDMA mode between different cable modem vendors that have not closely followed the DOCSIS 2.0 specification. Remember, cable networks are not dominated by burst noise in absence of ingress or narrow band interference. These two always occur together, but the narrowband interference can come and go, thus it is not apparent in a given 30 minute measurement time.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |