Cisco AGS+, Hardware Installation And Maintenance

Page: 35 / 146

Network
Connection
Preparation
Network
Connection Preparation
When
setting
up
your
system you must
consider
number
of
factors
related
to
the cabling required
for
your console
terminal connections
Each
of these cabling considerations
is
described
in
the
following
sections
RS-232 Connection
Prerequisites
variety of similar signaling
schemes
use the
name
RS-232
The
following
scheme
which
is
used
in
all
modular
and fixed-configuration
products
is
sufficient to
control
most
modems
and hardware
flow-control
schemes
This
scheme
provides six signals
per line
two of
them
outputs
Ground
Transmit
Data output
Receive
Data input
Ring Indicate input
Data
Terminal Ready output
Clear
To Send input
The
line
drivers
are supplied with bipolar 12 volt
power
an open output
signal
will
be
near
12
or
12V
The Receive Data
input has
10000
ohm
resistor to
the
12V
supply that helps prevent
open lines
from
ringing
and
causing spurious input to the
communication
server
An
open Receive
Data
line will
be
near
7V
but can vary
from
to
1OV
depending on temperature
and component
variation
Distance
Limitations
The
length of your networks
and
the
distance
between connections
depends on the type of signal
the
signal
speed and
the transmission
media the
type of cable
used
to
transmit the signals For
example
standard coaxial cable has
greater channel capacity
than twisted-pair cabling
The
distance
and
rate limits
in these descriptions
are the
IEEE recommended
maximum
speeds
and
distances
for
signaling
You
can usually get
good
results at speeds
and
distances
far
greater than
these
however the
maximum
distances are not
recommended
For instance
the
recommended
maximum
rate
for V.35
is
megabits per second
Mbps
but
is
commonly
used
at
Mbps without
any
problems
If you
understand
the
electrical
problems
that
might arise
and
can compensate for
them
you
should
get
good results
with
rates
and distances
greater than those
shown here however do
so at
your
own
risk
The
following
distance
limits are provided
as
guidelines
for planning
your
network
connections
before installation
FDDP Connections
The distance limitations for single-mode
and multimode
Fiber Distributed
Data
Interface
FDDI
stations are
listed
in Table
2-3 Both
FDDI
modes
provide 11
decibels
dB
of
optical
power
Table 2-3
FDDI
Maximum Transmission Distances
Transceiver Type
Max
Distance eetween
Stations
Single-mode
Up
to
24 mi 39
kin
Multimode Upto l.2niil.9km
2-8
AGS
Hardware Installation
and Maintenance