Cisco Cisco uBR-MC3Gx60V-RPHY Broadband Processing Engine Data Sheet
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Advanced RF Front End
The Cisco uBR7200 Series MC28U, MC28X, MC16U, and MC16X line cards combine the highest level of integration with enhanced RF
robustness and performance for the Cisco uBR7246VXR. The innovative design uses leading PHY chips from multiple vendors. Advanced
RF features include direct sampling of the upstream channels and automatic ingress noise cancellation.
The Cisco uBR7200 Series MC28U, MC28X, MC16U, and MC16X use technology patented by Cisco to determine carrier-to-noise ratio
(CNR) values for selected upstream channels. This technique, not offered by any other CMTS vendor, is a Cisco differentiator. Cable
operators routinely measure CNR as one means of characterizing the health of their cable networks. Understanding CNR, how it degrades
through a cascade of devices, and how it affects all the signals carried on the network are critical to ensuring reliable network operation..
Cisco’s revolutionary technique offers a higher degree of accuracy and flexibility when calculating this value. Conventional techniques for
estimating CNR of selected upstream channels are based upon Error Vector Magnitude (EVM) calculations. Cisco’s patented technique
achieves precise CNR measurements by scheduling timeslots on selected channels specifically for collecting signal and noise information.
The technique supports measurements on a node-by-node basis to analyze CNR on one or more specific modems of an upstream
channel—not supported using EVM-based calculations. Cisco uBR7200 Series MC28U, MC28X, MC16U, and MC16X meet or exceed
DOCSIS specifications for downstream CNR of 35 dB and 25 dB for upstream operation.
In addition, the Cisco uBR7200 Series MC28U and MC16U feature integrated upconverters. Depending on the specific model, either one
or two downstream (DS) modulators and eight or six upstream (US) burst receivers are offered on a single line card.
Superior MAC
The Cisco uBR7200 Series MC28U, MC28X, MC16U, and MC16X line cards feature dedicated MAC layer hardware for maximum
performance in large-scale deployments. The MAC layer hardware enables scalability to thousands of cable modems, simultaneously
providing hardware acceleration for sophisticated security features, such as DOCSIS 1.1 extensions to baseline privacy interface (BPI+), or
processor-intensive functions, such as concatenation, fragmentation, and payload header suppression (PHS) necessary to deploy advanced
data and voice services.
Flexible Software MAC Domain Configuration or Virtual Interfaces
Cisco BPEs support flexible upstream allocation and usage—known as software MAC domain configuration or virtual interfaces. Cable
operators can associate differing combinations of upstreams to downstreams. Upstreams are no longer fixed by their physical location, but
can be assigned to virtual upstream channels. For instance using a Cisco MC28U or MC28X, a cable operator can associate any
combination of upstreams (up to eight) to each of the two downstreams. Operators can configure one downstream, six upstreams, plus one
downstream and two upstreams, or can configure two independent 1x4 CMTS MAC domains. MAC domains can be configured according
to a particular class of service that groups downstreams and upstreams by application; e.g., commercial service requiring a higher QoS or
flat-rate residential service. Cable operators can configure MAC domains in a more flexible and dynamic manner to meet differing
customer demands and usage. If more capacity is required in one MAC domain, operators can reconfigure the BPE, as opposed to creating
a new MAC domain by installing a new cable line card.