To define the mapping between a destination protocol address and the
data-link connection identifier (DLCI) or Frame Relay permanent virtual circuit
(PVC) bundle that connects to the destination address, use the
frame-relay map command in interface configuration mode. To
delete the map entry, use the
no form of this command.
frame-relay map protocol protocol-address {dlci | vc-bundle vc-bundle-name} [broadcast] [ietf | cisco] [payload-compression {packet-by-packet | frf9 stac [one-way-negotiation] [ratio level] [skip-zero-sync] [software | hardware-options] | data-stream stac [one-way-negotiation] [ratio level] [software | hardware-options]}]
no frame-relay map protocol protocol-address
Syntax Description
protocol
|
One of the following values:
appletalk ,
decnet ,
dlsw ,
ip ,
ipx ,
llc2 , and
rsrb .
|
protocol-address
|
Destination protocol address.
|
dlci
|
DLCI number used to connect to the specified protocol
address on the interface. Acceptable numbers are integers from 16 through 1007,
inclusive.
|
vc-bundle
vc-bundle-name
|
A specific Frame Relay PVC bundle configured on the
interface.
|
broadcast
|
(Optional) Forwards broadcasts to this address when
multicast is not enabled (see the
frame-relay multicast-dlci command for more
information about multicasts). This keyword also simplifies the configuration
of Open Shortest Path First (OSPF) (see the “Usage Guidelines” section for more
detail).
|
ietf
|
(Optional) Internet Engineering Task Force (IETF) form of
Frame Relay encapsulation, based on RFC 1490 and RFC 2427. Used when the router
or access server is connected to another vendor’s equipment across a Frame
Relay network.
|
cisco
|
(Optional) Cisco-proprietary encapsulation method
consisting of a four-byte header, with two bytes to identify the DLCI and two
bytes to identify the packet type.
|
payload-compression
|
(Optional) Enables payload compression.
|
packet-by-packet
|
(Optional) Packet-by-packet payload compression using the
Stacker method.
|
frf9
stac
|
(Optional) Enables FRF.9 compression using the Stacker
method.
-
If the router
contains a CSA1, compression is
performed in the CSA hardware ( hardware compression).
-
If the CSA is
not available, compression is performed in the software installed on the
VIP22 (
distributed compression).
-
If the VIP2 is
not available, compression is performed in the main processor of the router (
software compression).
|
one-way-negotiation
|
(Optional) Enables one-way negotiation. Use this keyword if
your router will be negotiating compression with another device that is running
Cisco IOS Release 12.1(9) or earlier releases. Later Cisco IOS releases use a
two-way handshake by default to negotiate compression.
|
ratio
level
|
(Optional) Sets throughput versus compression ratio. This
option is available only with hardware compression. Possible values for the
level argument are as follows:
high
--high compression versus low
throughput
medium
--medium compression versus
medium throughput
low
--low compression versus high
throughput (default)
|
software
|
(Optional) Specifies that compression is implemented in the
Cisco IOS software installed in the main processor of the router.
|
hardware-options
|
(Optional) Choose one of the following hardware options:
caim
element-number
--Enables the
CAIM3 to perform
compression.
distributed
--Specifies that
compression is implemented in the software that is installed in a VIP2. If the
VIP2 is not available, compression is performed in the main processor of the
router (software compression). This option applies only to the Cisco 7500
series routers. This option is not supported with data-stream compression.
csa
csa_number
-- Specifies the CSA to
use for a particular interface. This option applies only to Cisco 7200 series
routers.
|
skip-zero-sync
|
(Optional) Causes compression frames to be numbered
starting from 1 rather than 0. Use this keyword if your router will be
interoperating with a device conforming to IBM partner conventions.
|
data-stream
stac
|
(Optional) Enables data-stream compression using the
Stacker method.
-
If the router
contains a CSA, compression is performed in the CSA hardware ( hardware
compression).
-
If the CSA is
not available, compression is performed in the main processor of the router
(software compression).
|
Command Default
No mapping is defined.
Command Modes
Interface configuration
Command History
Release
|
Modification
|
10.0
|
This command was introduced.
|
11.3
|
The
payload-compress frf9 stac keyword was added.
|
12.1(5)T
|
The
payload-compress data-stream stac keyword was added.
|
12.2(4)T
|
The
skip-zero-sync keyword was added.
|
12.2(13)T
|
The
vc-bundle vc-bundle-name keyword and argument
pair was added.
The
apollo ,
vines , and
xns arguments were removed because
Apollo Domain, Banyan VINES, and Xerox Network Systems are no longer available
in the Cisco IOS software.
The
one-way-negotiation keyword was
added.
|
12.2(28)SB
|
This command was integrated into Cisco IOS Release
12.2(28)SB.
|
12.2(33)SRA
|
This command was integrated into Cisco IOS Release
12.2(33)SRA.
|
12.2SX
|
This command is supported in the Cisco IOS Release 12.2SX
train. Support in a specific 12.2SX release of this train depends on your
feature set, platform, and platform hardware.
|
Usage Guidelines
Many DLCIs can be known by a router or access server and can send
data to many different places, but they are all multiplexed over one physical
link. The Frame Relay map defines the logical connection between a specific
protocol and address pair and the correct DLCI or PVC bundle.
The optional
ietf and
cisco keywords allow flexibility in the
configuration. If no keywords are specified, the map inherits the attributes
set with the
encapsulation frame-relay command. You can also use the
encapsulation options to specify, for example, that all interfaces use IETF
encapsulation except one, which needs the original Cisco encapsulation method
and can be configured through use of the
cisco keyword with the
frame-relay map command.
Data-stream compression is supported on interfaces and virtual
circuits (VCs) using Cisco proprietary encapsulation. When the
data-stream stac keyword is specified, Cisco encapsulation is
automatically enabled. FRF.9 compression is supported on IETF-encapsulated VCs
and interfaces. When the
frf9 stac keyword is specified, IETF encapsulation is automatically
enabled.
Packet-by-packet compression is Cisco-proprietary and will not
interoperate with routers of other manufacturers.
You can disable payload compression by entering the no frame-relay map payload command and then entering the
frame-relay map command again with one of the other
encapsulation keywords (ietf or
cisco ).
Use the
frame-relay map command to enable or disable payload compression on multipoint
interfaces. Use the
frame-relay payload-compression command to enable or disable payload compression on
point-to-point interfaces.
We recommend that you shut down the interface before changing
encapsulation types. Although shutting down the interface is not required, it
ensures that the interface is reset for the new encapsulation.
The
broadcast keyword provides two functions: it
forwards broadcasts when multicasting is not enabled, and it simplifies the
configuration of OSPF for nonbroadcast networks that will use Frame Relay.
The
broadcast keyword may also be required for
some routing protocols--for example, AppleTalk--that depend on regular routing
table updates, especially when the router at the remote end is waiting for a
routing update packet to arrive before adding the route.
By requiring selection of a designated router, OSPF treats a
nonbroadcast, multiaccess network such as Frame Relay in much the same way as
it treats a broadcast network. When the
frame-relay map command (with the
broadcast keyword) and the
ip ospf network command (with the
broadcast keyword) are configured, there is
no need to configure any neighbors manually. OSPF will run automatically over
the Frame Relay network as a broadcast network. (See the
ip ospf network interface command for more detail.)
Note |
The OSPF broadcast mechanism assumes that IP class D addresses are
never used for regular traffic over Frame Relay.
|
Examples
The following example maps the destination IP address 172.16.123.1 to
DLCI 100:
interface serial 0
frame-relay map ip 172.16.123.1 100 broadcast
OSPF will use DLCI 100 to broadcast updates.
The following example maps the destination IP address 172.16.123.1 to
the Frame Relay PVC bundle named “MAIN-1”:
interface serial 0
frame-relay map ip 172.16.123.1 vc-bundle MAIN-1 broadcast
The following example shows FRF.9 compression configuration using
the frame-relay map command:
interface serial2/0/1
ip address 172.16.1.4 255.255.255.0
no ip route-cache
encapsulation frame-relay ietf
no keepalive
shutdown
frame-relay map ip 172.16.1.1 105 ietf payload-compression frf9 stac
The following example shows data-stream compression configuration
using the
frame-relay map command:
interface serial0/0
frame-relay map ip 10.0.0.1 100 payload-compression data-stream stac