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DOCSIS Deployment Has Begun

Editor's Note: Cogeco Cable, Inc., an industry leader in the data-over-cable service offering has begun full-scale DOCSIS (Data Over Cable Service Interface Specification) deployment in its southern Ontario (near Toronto) market. To date, over 8,000 DOCSIS modems have been installed. This deployment verifies that DOCSIS is here today and that it works. The following article by Robin Lavoie, from CableLabs' Canadian member company Cogeco Cable, Inc., and by Steve Nevalsky, of Cisco Systems, Inc., expresses their viewpoint on how this broadband-based standard cable modem deployment is progressing.

his industry-leading DOCSIS deployment covers approximately 195,000 homes passed and is currently using five separate Cisco uBR7246 DOCSIS cable modem terminal station (CMTS) routers. The initial installation utilizes MC11 modem cards. These provide one downstream and one upstream DOCSIS channel per card. Until MC16 (one downstream/six upstream channels) modem cards are available (they will be in production at the time of this publication), six fiber nodes are being combined into a single upstream receiver. Although this architecture is not optimal, it does verify that DOCSIS technology works even in the presence of ingress noise due to the combining of many upstreams. Each CMTS has 500 1300 DOCSIS modems connected, with over 800 modems to a single MC11 in one CMTS. DOCSIS-based modems are being installed at the rate of 200 per day. In short, DOCSIS WORKS!

The cable modem used exclusively for this deployment is the Samsung InfoRanger cable modem, a DOCSIS standards-based modem that is currently in the process of DOCSIS certification at CableLabs.

A DOCSIS-based solution was chosen over several proprietary technologies for a number of reasons:

Some proprietary modems lack the desired robustness and noise immunity;
DOCSIS technology provides more flexibility by supporting a larger number of modems per upstream channel;
Cogeco Cable, Inc., has been actively involved in the DOCSIS program (and the original high-speed data group) and had planned this DOCSIS rollout many months ago;
Cogeco Cable, Inc., preferred not to continue to invest in proprietary designs which would only have to be upgraded later; and
DOCSIS technology provides a better long-term investment.

Cogeco Cable decided to be an early adopter of DOCSIS technology because of its goal to be a leader in delivering broadband solutions to its customer base. Cogeco Cable, in cooperation with Cisco Systems, Samsung Corp., and CableLabs, has accepted the responsibility to transition DOCSIS from a paper design to a real product and service. This effort represents the collective result of the past three years of the cable system operators working together with vendors to have products based on a new industry standard. Furthermore, the cable community will benefit from Cogeco Cable playing such an active role in this technology evolution.

Although the deployment has had its challenges, the performance of the system has been above expectations. The upstream and downstream average bandwidths consumed have been well below the maximum channel-throughput rates. Performance numbers measured indicate the uBR7246 can easily support 3,500 modems passing typical web-browsing-type traffic. Also, RF performance has been excellent. DOCSIS service and proprietary channels coexist reliably, allowing time for Cogeco Cable to transition older technology modems to new DOCSIS modems without an interruption in service. Also, the DOCSIS service has been assigned a low upstream frequency (22 MHz) verifying that the product works at the low end of the spectrum, which, studies have shown, is typically susceptible to higher levels of impulse noise.

Although there are many DOCSIS trials being performed by all of the major cable television operators, this deployment has extended beyond a trial into a full-scale commercial deployment. In fact, one uBR7246 has the following quantities of modems connected:

Cable6/0: 430 modems
Cable5/0: 330 modems
Cable4/0: 485 modems
Cable3/0: 236 modems

Total: 1,481

(See Figure 1, Distribution Network Diagram)

Figure 1. Distribution Network Diagram

In order to support the installation and troubleshooting of such a large number of modems, Cogeco Cable, Inc., has utilized a patent-pending tool developed by Cisco Systems, Inc. for identifying modems which are frequently re-ranging or adjusting their power levels too often. This information has allowed Cogeco Cable to identify quickly and efficiently problems which are plant related vs. problems which are due to a faulty modem or wiring within the customers' homes. Cogeco Cable has enhanced this tool by providing a script that automatically generates daily trouble reports.

In addition to the high level of performance demonstrated by the DOCSIS systems, this deployment has validated the quick modem acquisition times. For example, on one uBR7246 a total of 1,146 of the 1,231 modems (93%) were back on line within 10 minutes from an interface reset.

The tremendous success of this first full-scale DOCSIS deployment has demonstrated not only that DOCSIS has accomplished its goal of robust, interoperable cable modems, but that DOCSIS is here today and has gone beyond field trials into full commercial deployments.

DOCSIS Deployment Has Begun
Editor's Note: Cogeco Cable, Inc., an industry leader in the data-over-cable service offering has begun full-scale DOCSIS (Data Over Cable Service Interface Specification) deployment in its southern Ontario (near Toronto) market. To date, over 8,000 DOCSIS modems have been installed. This deployment verifies that DOCSIS is here today and that it works. The following article by Robin Lavoie, from CableLabs' Canadian member company Cogeco Cable, Inc., and by Steve Nevalsky, of Cisco Systems, Inc., expresses their viewpoint on how this broadband-based standard cable modem deployment is progressing.
his industry-leading DOCSIS deployment covers approximately 195,000 homes passed and is currently using five separate Cisco uBR7246 DOCSIS cable modem terminal station (CMTS) routers. The initial installation utilizes MC11 modem cards. These provide one downstream and one upstream DOCSIS channel per card. Until MC16 (one downstream/six upstream channels) modem cards are available (they will be in production at the time of this publication), six fiber nodes are being combined into a single upstream receiver. Although this architecture is not optimal, it does verify that DOCSIS technology works even in the presence of ingress noise due to the combining of many upstreams. Each CMTS has 500 1300 DOCSIS modems connected, with over 800 modems to a single MC11 in one CMTS. DOCSIS-based modems are being installed at the rate of 200 per day. In short, DOCSIS WORKS! The cable modem used exclusively for this deployment is the Samsung InfoRanger cable modem, a DOCSIS standards-based modem that is currently in the process of DOCSIS certification at CableLabs. A DOCSIS-based solution was chosen over several proprietary technologies for a number of reasons: Some proprietary modems lack the desired robustness and noise immunity; DOCSIS technology provides more flexibility by supporting a larger number of modems per upstream channel; Cogeco Cable, Inc., has been actively involved in the DOCSIS program (and the original high-speed data group) and had planned this DOCSIS rollout many months ago; Cogeco Cable, Inc., preferred not to continue to invest in proprietary designs which would only have to be upgraded later; and DOCSIS technology provides a better long-term investment. Cogeco Cable decided to be an early adopter of DOCSIS technology because of its goal to be a leader in delivering broadband solutions to its customer base. Cogeco Cable, in cooperation with Cisco Systems, Samsung Corp., and CableLabs, has accepted the responsibility to transition DOCSIS from a paper design to a real product and service. This effort represents the collective result of the past three years of the cable system operators working together with vendors to have products based on a new industry standard. Furthermore, the cable community will benefit from Cogeco Cable playing such an active role in this technology evolution. Although the deployment has had its challenges, the performance of the system has been above expectations. The upstream and downstream average bandwidths consumed have been well below the maximum channel-throughput rates. Performance numbers measured indicate the uBR7246 can easily support 3,500 modems passing typical web-browsing-type traffic. Also, RF performance has been excellent. DOCSIS service and proprietary channels coexist reliably, allowing time for Cogeco Cable to transition older technology modems to new DOCSIS modems without an interruption in service. Also, the DOCSIS service has been assigned a low upstream frequency (22 MHz) verifying that the product works at the low end of the spectrum, which, studies have shown, is typically susceptible to higher levels of impulse noise. Although there are many DOCSIS trials being performed by all of the major cable television operators, this deployment has extended beyond a trial into a full-scale commercial deployment. In fact, one uBR7246 has the following quantities of modems connected: Cable6/0: 430 modems Cable5/0: 330 modems Cable4/0: 485 modems Cable3/0: 236 modems Total: 1,481 (See Figure 1, Distribution Network Diagram)

Figure 1. Distribution Network Diagram
In order to support the installation and troubleshooting of such a large number of modems, Cogeco Cable, Inc., has utilized a patent-pending tool developed by Cisco Systems, Inc. for identifying modems which are frequently re-ranging or adjusting their power levels too often. This information has allowed Cogeco Cable to identify quickly and efficiently problems which are plant related vs. problems which are due to a faulty modem or wiring within the customers' homes. Cogeco Cable has enhanced this tool by providing a script that automatically generates daily trouble reports. In addition to the high level of performance demonstrated by the DOCSIS systems, this deployment has validated the quick modem acquisition times. For example, on one uBR7246 a total of 1,146 of the 1,231 modems (93%) were back on line within 10 minutes from an interface reset. The tremendous success of this first full-scale DOCSIS deployment has demonstrated not only that DOCSIS has accomplished its goal of robust, interoperable cable modems, but that DOCSIS is here today and has gone beyond field trials into full commercial deployments.