User's Manual

www.vyyo.com
System Configuration Introduction – p. 13
There are different configuration requirements for each layer and different
software tools accomplish this task. The configuration of the RF link is typically
unique to each installation with the particular downstream and upstream
frequencies, modulations and bandwidths being the critical parameters that must
be set on the modem and WMTS.
Whereas there is no set standard for implementing an RF link, DOCSIS is a fully
specified protocol as are the upper layers (IP, E1/T1 or PSTN). The following
sections will describe the currently available system components (equipment)
then detail how to configure each of them in turn.
1.2 Equipment Capabilities
There are several different modems available, the simplest being the DOCSIS
modems with IP-only capability. All of the other modems use these as their
foundation.
The WMTS used at the head end is the other major component. There is only
one basic configuration, which is augmented with additional plug-in cards to
accommodate E1/T1 and PSTN capabilities.
NOTE: The term WMTS was originally conceived as
“eVyyoed” CMTS for use in a cable plant, hence the “X”.
This was followed by WMTS in which the “W” indicates a
“wireless” CMTS. For practical purposes these terms are
interchangeable and in some places the software uses
the term “WMTS” when referring to any one of these
systems.
1.3 WMTS
The basic WMTS is a chassis with a power supply and a mid-plane PCI bus that
accommodates plug-in cards at the front and rear. Two redundant power supply
cards are provided at the right end of the front of the chassis.
The minimum required hardware configuration for an IP-only system consists of
one "HOST" card and three "Universal" cards. One Universal card acts as a
"Control and Forward" (C&F) card, one as the "Upstream" digital card and one as
the "Downstream" digital card. These latter two cards are attached to RF cards
in the rear slots.
E1/T1 capability may be added by replacing the Host card with a Master4 card,
and adding one or two E1/T1 interface cards in the rear slots to provide 12 or 24
E1/T1 ports, respectively. An DS3 version of the Master4 card which allows 28
T1 connections is also available. This card has two coax connectors (one for
receive and one for transmit) in place of the E1/T1 interface cards.
The HOST or Master4 card serves as the PCI bus arbiter and provides the
system clock and timing. When the WMTS boots, the Master4 card initializes,
then identifies the C&F card. The C&F card then directs the configuration and
downloading of relevant application software. The C&F card is connected
through a 100 BaseT Full Duplex connection to the switch or router and used to
transport data (including management packets) through the system.