ZyXEL Communications Cable Modem, Руководство пользователя

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VLC1324G User’s Guide
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H A P T E R
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VLC Overview
This chapter introduces the VDSL2 line card's general features, default settings and hardware.
1.1 VLC Overview
The VLC VDSL2 Line Card is perfect for ISPs or large building applications seeking to
provide high bandwidth broadband services to subscribers while minimizing costs. One VLC
provides VDSL2 service for 24 subscribers over existing telephone wiring, thus avoiding the
cost and hassle of installing new wiring.
The line from the user carries both the VDSL2 and the voice signals. For each line, the splitter
card separates the high frequency VDSL2 signal from the voice band signal and feeds the
VDSL2 signal to the line card, while the voice band signal is diverted to the central office
switch or PBX (Private Branch Exchange).
Use the Telco-50 connector pin assignments in
Section 2.3 on page 25 along with the
directions and safety warnings in the IES User’s Guide to install the line card and make the
necessary connections.
1.2 VDSL2 Profiles Overview
Here are the VDSL2 maximum transmission rates that the VLC supports at the time of writing.
The actual transfer rates will vary depending on what the subscriber’s device supports, the line
conditions and the connection distance.
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1.3 Key Features
Here is a partial list of the VLC’s features.
Table 1 VDSL2 Profile Maximum Transfer Rates
VDSL2 PROFILE MAXIMUM DOWNSTREAM MAXIMUM UPSTREAM
8a/b/c/d 85 Mbps 18 Mbps
12a/b 85 Mbps 50 Mbps
17a 100 Mbps 50 Mbps
1. These are the highest link rates attained in testing. Actual data transfer rates will vary. These rates are for a
single port. The ports cannot all simultaneously link up at these rates.