Cisco HyperSwitch A100, Руководство пользователя

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System Software Types
EIAITIA-232
driver
Flash
EPROM
driver
The
operating
system
OS
real-time operating
system
supports
the
following
functions
Task
arbitration
Intertask
communication
support
Task
management create
activate
suspend
resume
delete
Memory
management
Process
interrupt
Process
exception
The
Boot
Program
The
boot
program
activates
when
the
system
is
reset
The
boot
program
loads online software
from
Flash
EPROM
to
DRAM
and
activates it
When
online software
and
the
system debugger
are not
in
Flash
EPROM
the boot
program
loads the load
module from
workstation connected
through
the
Ethernet
interface saves
the load
module
in
Flash
EPROM
and
restarts the
system
Connection
Control
The HyperSwitch
AlOO
performs
resource allocation
and
path
establishment
when
PVC
setup
request
occurs
The number
of
VPI
and
VCI
bits
necessary
for
ATM
connection are configured
per line
total
of
12
bits
is
supported
for
VPI
and
VCI up
to
4096
channels
per
line Because
VPIsIVCIs
are
distributed
to
PVC
and
SVC
when
using
SVC
the
number
of available
PVCs
diminishes
accordingly
The
HyperSwitch
Al00
supports
12
bits
of
VPLIVCI
address
space
The
default
number
of allocated
VPIVCI
bits is
four
for
YPI
and
eight
for
VCI
The
range
of
VCIs
that
can
be
assigned using eight
bits is to
255
255
VCI
values
can be
used for
PVCs
and
SVCs
To
avoid
conflict
in
the assignment of
PVCs
and
SVCs
ensure
the
following
Of
the
255
VCI
values available through
127
are
allocated for
PVCs
and
128
through
255
are
allocated for
SVCs
When
using
ITU-T
the four
least
significant
VCI
bits
through
15
are
reserved
xxxx xxxx
When
using
ATM
Forum
the
five least
significant
VCI
bits
through
31
are reserved
xxxx
xxxx
The most
significant
bit
is
set to
for
PVC
or
for an
SVC
xxxx xxxx
The HyperSwitch
AlOO
can
have both
point-to-point
and
point-to-multipoint
connections
The
following
list
indicates the current
number
of
each
connection
type per
system The
number
of
point-to-point
connections does not
decrease
if
the
maximum
number
of point-to-multipoint
connections
are established
and
vice
versa The
number
of possible
PVCs
and
SVCs
follow
1-8
Cisco HypØrSwitch
A100
User Guide