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The Cisco uBR Broadband cable subsystem consists of up to 4 modem cards which plug in to the Universal chassis. Each modem card is entirely independent from a radio frequency (RF) standpoint, while all modem cards in the chassis share the Router subsystem. This provides maximum cost-effectiveness and flexibility to the cable operator by amortizing the cost of the routing across all the modems in each chassis, while allowing each of four modem cards to serve a dedicated group of subscriber modems. This flexibility further enables the use of different types of subscriber devices if desired.
Cisco will ultimately offer a wide variety of modem cards, depending on the types of subscriber modems that are needed. The modem cards Cisco offers are all fully compliant with the MCNS DOCSIS specification.
MC-11: 1 Downstream and 1 Upstream
The MC-11 Modem Card contains one 64-QAM downstream modulator and one QPSK upstream demodulator on a single card. The MC-11 modem supports both two-way and telephone-return modems simultaneously. The MC-11 offers cable operators the lowest capital cost for an initial entry point into a market, and is therefore ideal for smaller cable systems or nodal areas with low penetration of cable data service.
MC-16: 1 Downstream and 6 Upstream
The MC-16 Modem Card contains one 64-QAM downstream modulator and six QPSK upstream demodulators on a single card. The MC-16 Modem supports both two-way and telephone-return modems simultaneously. The MC-16 provides a very favorable overall cost per subscriber modem, and is well suited for deployment in medium to large cable systems with good penetration of cable data service.
MC-26: 2 Downstream and 6 Upstream
The MC-26 Modem Card contains two 64-QAM downstream modulators and six QPSK upstream demodulators on a single card. The MC-26 supports both two-way and telephone-return modems simultaneously. The MC-26 provides the most cost-effective solution on the market on a per-subscriber basis, and is designed to be the workhorse product for medium to large cable systems as their cable data service grows beyond the initial rollout to full-scale market deployment. The MC-26 also allows separate provisioning of residential and commercial users.
The Cisco uBR7246 Broadband Subsystem:
Contains four modem card slots, which maximizes network capacity per chassis while minimizing both rack space utilization and overall cost of deployment.
Accepts any modem card in any slot, which supports a wide variety of subscriber units, promotes interoperability, and simplifies hardware configuration.
Supports both two-way and telephone-return MCNS modems on the same card, which enables deployment of both two-way telephone return in the same channel and reduces hardware cost.
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Modem Card Physical Configuration |
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|---|---|
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Modem Cards/chassis |
4 |
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Dimensions (H x W x D) |
1.35 x 13.50 x 10.56 in (3.43 x 34.29 x 26.82 cm) |
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Modem Card RF Specifications | |
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Downstream Modulation |
64 QAM/256 QAM |
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Downstream Bit Rate |
27 Mbps (effective)/40 Mbps (effective) |
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Upstream Modulation |
QPSK/16 QAM |
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Upstream Bit Rate |
22.5 Mbps (effective)/5.0 Mbps (effective) |
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Output Frequency |
44 MHz |
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Modem Card Power Requirements | |
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Heat dissipation |
30W |
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AC-input voltage |
120-240 VAC wide input with power factor correction |
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AC-input current rating |
0.25A maximum at 120 VAC 0.125A maximum at 240 VAC |
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AC-input cable |
Three-wire cable, with a three-lead receptacle on the power supply end, and a country-dependent plug on the power source end |
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Frequency |
50/60 Hz |
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Modem Card Software Requirements |
Cisco IOS Release 11.3(3)T, or later, running on the Cisco uBR7246 Universal Broadband Router, installed at the cable headend |
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Operating Temperature |
23 (o) to 113 (o) F (-5 (o) to 45 (o) C) |
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Non-operating Temperature |
-13 (o) to 95 (o) F (-25 (o) to 70 (o)C) |
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Relative Humidity |
5 to 95% noncondensing |
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Noise level |
38 dBa maximum at desktop 43 dBa maximum in an office |
The Cisco uBR7246 Broadband subsystem conforms to the following set of safety and regulatory standards:
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Safety |
Immunity |
|---|---|
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UL 1950 |
IEC 1000-3-2 (harmonics) |
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CSA 22.2-No. 950 |
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EN60950 |
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AUSTEL TS001 |
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AS/NZS 3260 |
For software specification information, access Cisco Connection Online at http://www.cisco.com.
Please see Table 5-92: Cisco uBR7246 Documentation Part Numbers .