Ref: 99980070
Title: Questions and Answers/Broadband
Date: 8/1/86

Copyright 3Com Corporation, 1991.  All rights reserved.

Following are the most commonly asked questions about broadband
networks.

Q:  Do broadband networks require amplifiers regardless of their
size?

A:  Amplifiers are only used in broadband networks as required to
meet the system performance standards set forth in the system
specification.  Through the branching and splitting
characteristics of the network, signals can often be
distributed in an efficient manner in smaller systems without
the need for amplifiers.


Q:  Are the taps used in broadband the same as those used in
baseband networks?

A:  No. Baseband networks use resistive pressure taps.  These are
installed and operated quite differently from the directional
coupler tap used in broadband systems.  A resistive pressure
tap interfaces by coring the cable at the location in which
it is to be installed.  Once this is done, the tap fits
around the outside diameter of the cable used.  All broadband
taps use a standard interface.  They have been designed to
prevent high radiation and water leakage, and to give high
reliability.


Q:  Can customers use their installed frequency translators,
remodulators, or modems on the Bridge Broadband network?

A:  Bridge Broadband products employ a very sophisticated scheme
whereby the channel remodulator performs reliable collision
detection and the intelligent modem locks onto the optimal
operational level.  The Bridge Broadband products will not
operate with other frequency translators, remodulators, or
modems, even if they are configured for the same frequency
channel.  Furthermore, the CR/5 and the RFM/5 are not
compatible with other vendor's products.  The Bridge
Broadband products, however, coexist with other broadband
systems.


Q:  Does a broadband network have to be FCC certified?

A:   A broadband local network falls under the heading of a
Master Antenna Television (MATV) distribution system, which
does not require FCC approval.  In other words, the FCC
regulations concerning the CATV community do not apply to
the broadband network user.  However, if the signal egress
(signal radiation) of the network is interfering with FCC
protected aeronautical frequency bands, the FCC would get
involved to correct the problem.


Q:  Do different network IDs need to be specified when networks
are connected via the IB/1 or IB/2?

A:  No. When networks are connected via the IB/1 or IB/2, they
will be treated as an extended network.  A single network ID
must be used for both segments connected by the IBs.





