NAME
pvcarp - Interphase S/ATM 4615 adapter PVC/ARP Interface
SYNOPSIS
/bin/pvcarp -a
/bin/pvcarp -d hostname
/bin/pvcarp -f filename
/bin/pvcarp -s hostname [link:]vci_num [ rate_in_mbits ] [
encapsulation method ]
AVAILABILITY
This command is available from the Interphase S/ATM 4615
software distribution. It is part of the evaluation PVC
driver interface which supports IP over ATM PVCs and uses
RFC1483 IP LLC/SNAP encapsulation.
DESCRIPTION
pvcarp sets, deletes and displays Internet address to VC
mapping for PVC connections for the Interphase S/ATM 4615
adapter. The PVC interface simply uses the system ARP table
to map an IP address to a PVC value. The PVC value is
entered on the command line in either a decimal (e.g. 64) or
hexadecimal (e.g. 0x40) format. Optional link definitions
can be made to differentiate between multiple physical ATM
interfaces. Link numbers range from zero to n with zero
being the default.
Additionally, the command allows the definition/association
of transmission rates with a PVC. Up to four different rates
can be defined in addition to the default best effort rate.
This default rate is viewed as running at a lower priority
and is configured to run at the media rate during driver
initialization and can not be modified. It is serviced if
there is any bandwidth left after servicing the four defin-
able high priority rates (i.e. best effort).
As there are only four high priority rate, the number of
different rates specified in all the active PVCs can not
exceed 4. If a fifth rate is defined with a pvcarp command,
the command will fail with an invalid parameter error. Note
that multiple PVCs that are set to the same rate will use a
single rate queue and frames for that rate will be transmit-
ted in a FIFO fashion. Also, the total rate specified in all
the active PVCs that use high priority rate queues should
not exceed the line rate, otherwise data will not be
transmitted at the specified rates. No system check is done
on this at this time.
A new rate can be defined during a pvcarp IP to VC mapping
if less that four rates are currently in use or all the PVCs
for a given rate are deleted, thus making a rate available.
The resolution of the rate queues is limited and in general,
the lower the rate, the better the resolution of the rate
queue. If the rate queue cannot be set to the specified
rate, it is configured to the highest possible rate below
the specified rate.
The set version of the pvcarp command has a final option to
specify Null IP frame encapsulation rather than LLC/SNAP, to
accommodate system using this frame format. If no option is
specified, IP LLC/SNAP is the default. A "null" option can
be used to specify Null IP encapsulation. The "ipllc"
option can be used to also explicitly request LLC/SNAP and
to add clarity to description files.
The rate and encapsulation options are both optional possi-
tionally sensative options. To accommodate environments
where no rate definitions are used, if only one optional
parameter specified, it is check for first being a rate
definition and if not a rate, checked as an encapsulation
variable.
Use the pvcarp -a command to display the Internet-to-VC map-
ping table to see the defined options of the PVCs.
OPTIONS
-a This version of the command is used to get and display
a PVC definition.
-d This version of the command is used to remove a PVC
definition.
-f This version of the command is used to define or update
a ARP/PVC definition in the driver via a file of defin-
itions, where each line is in the format of the
/bin/pvcarp -s version of the command.
-s This version of the command is used to create an Inter-
net address to VC mapping. The VCI number
[link:]vci_num is given as a decimal (64) or hexade-
cimal (0x40) number. The optional link number is used
to specify the physical ATM link number in a multicard
implementation. It may also be decimal or hexadecimal
in format and if absent assumed to be link zero. The
rate rate_in_mbits is optional and is given as a
decimal or hexadecimal number in Mbits/sec. If no rate
is specified, low priority media (ABR) rate rate queue
is used. The encapsulation method is also optional and
is given an a string, which may be either "null" for
Null IP encapsulation or "ipllc" for IP LLC/SNAP encap-
sulation (the default).
EXAMPLES
To define the remote system grumpy-atm to be associated with
VC 64 on link zero and use the default ABR rate and default
IP LLC/SNAP encapsulation, the command could be:
example% pvcarp -s grumpy-atm 64
The same result would have been obtained with:
example% pvcarp -s grumpy-atm 64 ipllc
To define the remote system sneezy-atm2 to be associated
with VC 128 on the second ATM link and use a 33Mbit rate and
null IP encapsulation, the command could be:
example% pvcarp -s sneezy-atm2 1:0x80 33 null
Note that the second link (normally /dev/ia1) is specified
as 1: and the optional hexadecimal value for 128 was used.
This could also have been in the form:
example% pvcarp -s sneezy-atm2 1:128 33 null
NOTES
Because the pvcarp -s and pvcarp -f versions of the command
manipulate the ARP table and internal kernel PVC tables,
they must be run as root.
SEE ALSO
arp(8C), vctbl(8)
S/ATM 4615 User's Guide