Formats; Checks; And Timing - Cisco 7513 Hardware Installation And Maintenance Manual

NRZ
and NRZI

Formats

All data
inverted
signals maintain
during
signal
and
the absence
than
determining
All interface
connections
Maintaining

Checks

Redundancy
Cyclic
All data
support
detect
predetermined
the
frame
divisible
predetermined
assumes
The
designators
FCS
the
Thirty-two
32-bit
retransmits
less
Sixteen-bit
used
extensively
point-to-point transmission
LANs
Router
the
Modes

and Timing

Signal
Data communications
of the clock
connected
You
normally
router
configuration
DTE mode
In
remote
modem
as
DCE
device
cables
remote
communications
interfaces
NRZI
formats Both
formats
constant
levels
voltage
and decoded
bit interval
are
but the presence
levels
interprets
of data
no
transition
as
NRZ
absolute values
NRZI
also
types support
IBM
in environments
the Router
for configuration
communications
interfaces
CRC
CRC
32-bit
is an error-checking
The
transmitted data
errors in
number
calculate
to
FCS
the sender the
appends
number
the predetermined
by
number
the sender
that
transmission
that
occurred
error
16 and
32 indicate
CRC
Sixteen-bit which
transmits
CRC
bit which
transmits
CRC
transmits streams
longer
Both and
the sender
CRC
most
the
is
widely
with wide-area networks
standards
the section
See
Configuring
for configuration
instructions
ports operate
uses and
the port
signal that
DCE mode
In the port supplies
DCE
when
use
connecting
DCE
To
set
up port interface
as
command
the
to set internal
which most
the commonly
is
You
or external device
normally
CSUIDSU DTE
Most
or
To
provides set up
port
When
the port recognizes the
DCE
device
both
nonreturn zero
support to
two
use different
voltage
with
no
transitions
signal
and
using absolute values
of data
the beginning of
at
NRZI
uses
differential
encoding
the factory default on
all
which
format is commonly
See
the section
Configuring
instructions
use 16-bit
redundancy
cyclic
that
uses
technique
frame
sender of data
divides
remainder
or frame check
value the
so
to that
message
The
receiver divides the
FCS
used calculate the
to
and
sends
to
request
number check
the of
digits
per
streams of
8-bit
characters
streams of
16-bit characters
better
at faster
rates
it provides
must
the receiver use the same
method
used the United
throughout
WANs
IEEE-802
specifies
it an option often used
specify as
It is
Check
32-Bit
Redundancy
Cyclic
DCE DTE mode
in either
or
mode
remote
the of the
own clock
its
signal
DTE
the router device
to
DCE
you must
use
adapter
clock
speed
used mode
the port uses
DTE
when
use
connecting
interfaces an external
require
DTE
you need
interface
as
DTE
cable
automatically
it
Network
Preparing
NRZ
and
nonreturn
to zero
NRZ
for transmission
levels
no
return
to
zero voltage
level
NRZI
uses the same
constant
bit interval transition
as signal
decode
rather
to
signals
common
interface most
types is
used EIA/TIA-232
with
NRZI Format
the chapter
in
CRC
check
default but also
by
numeric
calculated value
frame message
the the
bits in
FCS
Before sends
it
sequence
frame
the contents
are exactly
frame
contents the
same
by
the not the receiver
If result
is
frame
the sender resend the
to
frame
used calculate
that
are to
FCS
16-bit
generates
FCS
32-bit Because
generates
ongoing detection
error
setting
and Europe and
States
CRC
and some
32-bit
SMDS
on
networks
the chapter
in
Maintaining
mode
the the source
depends on
which
device the port
to is
PC
such
host or another
as
and
cable use the clockrate
clock
by
signal supplied
DCE
the router device
to
which remote
clock the
signal
DTE
connect
only adapter
from
uses the clock the
signal
for Installation
Preparing
Connections
to
by
with
it is
and
such
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