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ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Table Of Contents

ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Finding Feature Information

Contents

Prerequisites for ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Restrictions for ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Information About ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Benefits of ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Flexible Pool of Bandwidth

Greater Service Resilience When Links Fail

Scalability

Link Integrity Protocol Control Messages

Variable Bandwidth Class Support

Class A (Single Link)

Class B (All Links)

Class C (Threshold)

Load Balancing with ASR1K Frame Relay-Multilink (MLFR-FRF.16)

How to Enable ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Configuring a Multilink Frame Relay Bundle

Configuring a Multilink Frame Relay Bundle Link

Monitoring and Maintaining ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Examples

Configuration Examples for ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Example: Configuring Multilink Frame Relay

Example: Configuring Variable Bandwidth Class Support

Additional References

Related Documents

Standards

MIBs

RFCs

Technical Assistance

Feature Information for ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Glossary


ASR1K Frame Relay-Multilink (MLFR-FRF.16)


First Published: July 25, 2011
Last Updated: July 25, 2011

The ASR1K Frame Relay-Multilink (MLFR-FRF.16)Multilink-Frame Relay (MLFR-FRF.16) feature is based on the Frame Relay Forum Multilink Frame Relay UNI/NNI Implementation Agreement (FRF.16.1) on the Aggregation Service Routers. This feature provides a cost-effective way to increase bandwidth for particular applications by enabling multiple serial links to be aggregated into a single bundle of bandwidth. Multilink Frame Relay (MFR) is supported on User-Network Interfaces (UNI) in Frame Relay networks.

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest feature information and caveats, see the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the "Feature Information for ASR1K Frame Relay-Multilink (MLFR-FRF.16)" section.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.

Contents

Prerequisites for ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Restrictions for ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Information About ASR1K Frame Relay-Multilink (MLFR-FRF.16)

How to Enable ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Configuration Examples for ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Additional References

Feature Information for ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Glossary

Prerequisites for ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Multilink Frame Relay (MLFR) must be configured on the peer device.

Restrictions for ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Only the 2-octet Frame Relay format is supported.

Only T1 and E1 speed members are supported in a bundle.

All member links of a bundle must be of the same type.

The supported SPA types are as follows:

SPA-2XCT3/DS0

SPA-4XCT3/DS0

SPA-8XCHT1/E1

SPA-1XCHOC12/DS0

SPA-1XCHSTM1/OC3

This feature does not support the following features:

3-or 4-octet headers

Data-link connection identifier (DLCI) address mapping

Discard Eligibility (DE) bit manipulation

E1/T1 fractional links within the bundle

Frame Relay broadcast queue

Frame Relay backward explicit congestion notification (BECN) and forward explicit congestion notification (FECN) counting

Frame Relay PVC interface priority queueing (PIPQ) including DLCI prioritization

Frame Relay switching including NNI and FRF2.1

Frame Relay Traffic Policing (FRTP)

Frame Relay Traffic Shaping (FRTS)

FRF.12 Fragmentation

FRF.16.1 Fragmentation

Generic Traffic Shaping (GTS)

Inverse Address Resolution Protocol (Inverse ARP )

Permanent Virtual Circuit (PVC) configuration over MFR bundle interface

Point-to-multipoint subinterfaces

Switched Virtual Circuits (SVC)

ISDN interfaces and any type of virtual interface cannot be a bundle link.

The Multilink Frame Relay MIB (RFC 3020) is not supported.

FRF.9 hardware compression over MFR is not supported.

Information About ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Benefits of ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Link Integrity Protocol Control Messages

Variable Bandwidth Class Support

Load Balancing with ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Benefits of ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Flexible Pool of Bandwidth

By combining multiple physical interfaces into a bundle, you can design a Frame Relay interface that has more bandwidth than is available from any single physical interface. For example, many new network applications require more bandwidth than is available on a T1 line. One option is to invest in a T3 line; however, T3 lines can be expensive and are not available in some locations. Multilink Frame Relay provides a cost-effective solution to this problem by allowing multiple T1 lines to be aggregated into a single bundle of bandwidth.

Greater Service Resilience When Links Fail

Greater service resilience is provided when multiple physical interfaces are provisioned as a single bundle. When a link fails, the bundle continues to support the Frame Relay service by transmitting across the remaining bundle links.

Scalability

MLFR bundles—The following table shows the maximum number of MLFR bundles supported according to the number of links in a bundle.

Table 1 Maximum MLFR Bundles

Links per Bundle
Number of MLFR Bundles

1

992

2

496

3

330

4

248


Frame Relay DLCI—You can configure as many Frame Relay DLCIs on MLFR subinterfaces as MLFR bundles. The maximum number of Frame Relay DLCI that you can configure on MLFR subinterfaces and in one MLFR bundle is 1024.

MLFR subinterface—Because only point-to-point interfaces are supported, the number of DLCIs supported is equal to the number of subinterfaces. Therefore, the maximum number of MLFR subinterfaces and the maximum number of MLFR interfaces supported in one bundle is 1024.

Physical Links—The maximum number of physical links in a bundle is 10.

Link Integrity Protocol Control Messages

For link management, each end of a bundle link follows the MFR Link Integrity Protocol and exchanges link-control messages with its peer (the other end of the bundle link). For a bundle link to be brought up, each end of the link must complete an exchange of ADD_LINK and ADD_LINK_ACK messages. To maintain the link, both ends periodically initiate the exchange of HELLO and HELLO_ACK messages. This exchange of hello messages and acknowledgments serves as a keepalive mechanism for the link. If a router is sending hello messages but not receiving acknowledgments, it will resend the hello message up to a configured maximum number of times. If the router exhausts the maximum number of retries, the bundle link line protocol is considered down (nonoperational).

The bundle link interface's line protocol status is considered up (operational) when the peer device acknowledges that it will use the same link for the bundle. The line protocol remains up when the peer device acknowledges the hello messages from the local router.

The bundle interface's line protocol status is considered up when the Frame Relay data link layer at the local router and peer device is synchronized using the Local Management Interface (LMI), when the LMI is enabled. The bundle line protocol remains up as long as the LMI keepalives are successful.

Variable Bandwidth Class Support

Multilink-Frame Relay (MLFR-FRF.16) variable bandwidth class support allows you to specify the criterion used to activate or deactivate a Frame Relay bundle.

Class A (Single Link)

The Frame Relay bundle is provisioned when one or more bundle links indicate by issuing a BL_ACTIVATE message that operational bandwidth is available. When this occurs, the bundle emulates a physical link by issuing a PH_ACTIVATE message to the data link layer.

When the operational bandwidth of a bundle link fails to meet operational requirements (for instance, if it is in rollback mode), the bundle link issues a BL_DEACTIVATE message. When all bundle links are down in a class A bundle, a PH_DEACTIVATE message is sent to the data link layer, indicating that the Frame Relay bundle cannot accept frames.


Note The activate and deactivate messages are implementation-oriented messages only. They are not visible in the output of the debug commands.


Class B (All Links)

The Frame Relay bundle is provisioned when all bundle links indicate by issuing a BL_ACTIVATE message that operational bandwidth is available. When this occurs, the bundle emulates a physical link by issuing a PH_ACTIVATE message to the data link layer.

When the operational bandwidth of a bundle link fails to meet operational requirements (for instance, if it is in loopback mode), the bundle link issues a BL_DEACTIVATE message. When any bundle link is down in a class B bundle, a PH_DEACTIVATE message is sent to the data link layer, indicating that the Frame Relay bundle cannot accept frames.

Class C (Threshold)

The Frame Relay bundle is provisioned when the minimum number of links in the configured bundle issue a BL_ACTIVATE message. When this occurs, the bundle emulates a physical link by issuing a PH_ACTIVATE message to the data link layer.

When the number of bundle links that are issuing a BL_ACTIVATE message falls below the configured threshold value, a PH_DEACTIVATE message is sent to the data link layer, indicating that the Frame Relay bundle cannot accept frames.

Load Balancing with ASR1K Frame Relay-Multilink (MLFR-FRF.16)

MFR provides load balancing across the bundle links within a bundle. If a bundle link chosen for transmission happens to be busy transmitting a long packet, the load-balancing mechanism can try another link, thus solving the problems seen when delay-sensitive packets have to wait.

How to Enable ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Configuring a Multilink Frame Relay Bundle

Configuring a Multilink Frame Relay Bundle Link

Monitoring and Maintaining ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Configuring a Multilink Frame Relay Bundle

Perform this task to configure the bundle for multilink Frame Relay.

SUMMARY STEPS

1. enable

2. configure terminal

3. interface MFRinterface-number

4. frame-relay multilink bandwidth-class [a | b | c [threshold]]

5. frame-relay intf-type [dce | dte]

6. frame-relay multilink bid name

7. exit

8. interface MFRinterface-number.subinterface-number point-to-point

9. ip address ip-address mask

10. frame-relay interface-dlci dlci

11. end

12. show frame-relay multilink

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

Enter your password if prompted.

Step 2 

configure terminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3 

interface MFRinterface-number

Example:

Router(config)# interface MFR1

Configures a multilink Frame Relay bundle interface and enters interface configuration mode.

Step 4 

frame-relay multilink bandwidth-class [a | b | c [threshold]]

Example:

Router(config-if)# frame-relay multilink bandwidth-class a

(Optional) Specifies the bandwidth class criterion used to activate or deactivate a Frame Relay bundle.

Class A (single link)—The bundle will activate when any bundle link is up and will deactivate when all bundle links are down (default).

Class B (all links)—The bundle will activate when all bundle links are up and will deactivate when any bundle link is down.

Class C (threshold)—The bundle will activate when the minimum configured number of bundle links is up (the threshold) and will deactivate when the minimum number of configured bundle links fails to meet the threshold.

Note If no bandwidth class criterion is specified by using the frame-relay multilink bandwidth-class command, the Frame Relay bundle will default to class A (single link).

Step 5 

frame-relay intf-type [dce | dte]

Example:

Router(config-if)# frame-relay intf-type dce

Configures a device to function as the data communication equipment (DCE).

dce—(Optional) Router or access server functions as a switch connected to a router.

dte—(Optional) Router or access server is connected to a Frame Relay network.

Note Only one end of a link should be configured as the DCE. The other end will function as the data terminal equipment (DTE), which is the default setting.

Step 6 

frame-relay multilink bid name

Example:

Router(config-if)# frame-relay multilink bid router1

(Optional) Assigns a bundle identification name to a multilink Frame Relay bundle.

The bundle identification (BID) will not go into effect until the interface has gone from the "down" state to the "up" state. One way to bring the interface down and back up again is by using the shutdown and no shutdown commands in interface configuration mode (assuming the physical state of the link is always up).

Step 7 

exit

Example:

Router(config-if)# exit

Exits interface configuration mode and returns to global configuration mode.

Step 8 

interface MFRinterface-number.subinterface-number point-to-point

Example:

Router(config-if)# interface MFR1.1 point-to-point

Configures a point-to-point multilink Frame Relay subinterface and enters subinterface configuration mode.

Step 9 

ip address ip-address mask

Example:

Router(config-subif)# ip address 10.0.1.1 255.255.255.0

Configures the IP address for the subinterface.

Step 10 

frame-relay interface-dlci dlci

Example:

Router(config-subif)# frame-relay interface-dlci 100

Assigns a data-link connection identifier (DLCI) to a Frame Relay subinterface and enters Frame Relay DLCI configuration mode.

The DLCI range is from 16 to 1007.

Step 11 

end

Example:

Router(config-fr-dlci)# end

Exits Frame Relay DLCI configuration mode and returns to privileged EXEC mode.

Step 12 

show frame-relay multilink

Example:

Router# show frame-relay multilink

(Optional) Displays the current Frame Relay multilink configuration.

Configuring a Multilink Frame Relay Bundle Link


Tip To minimize latency that results from the arrival order of packets, Cisco recommends bundling physical links of the same line speed in one bundle.


Perform this task to configure a bundle link interface for multilink Frame Relay.

SUMMARY STEPS

1. enable

2. configure terminal

3. interface Serial number

4. encapsulation frame-relay MFRnumber [name]

5. frame-relay multilink lid name

6. frame-relay multilink hello seconds

7. frame-relay multilink ack seconds

8. frame-relay multilink retry number

9. end

10. show frame-relay multilink

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

Enter your password if prompted.

Step 2 

configure terminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3 

interface Serial number

Example:

Router(config)# interface Serial 5/0

Selects a physical interface and enters interface configuration mode.

Step 4 

encapsulation frame-relay MFRnumber [name]

Example:

Router(config-if)# encapsulation frame-relay MFR1

Creates a multilink Frame Relay bundle link and associates the link with a bundle.

Step 5 

frame-relay multilink lid name

Example:

Router(config-if)# frame-relay multilink lid first-link

(Optional) Assigns a bundle link identification name with a multilink Frame Relay bundle link.

The bundle link identification (LID) will not come into effect until the interface has gone from the "down" state to the "up" state. One way to bring the interface down and back up again is by using the shutdown and no shutdown commands in interface configuration mode.

Step 6 

frame-relay multilink hello seconds

Example:

Router(config-if)# frame-relay multilink hello 9

(Optional) Configures the interval at which a bundle link will send out hello messages.

The default value is 10 seconds.

Step 7 

frame-relay multilink ack seconds

Example:

Router(config-if)# frame-relay multilink ack 6

(Optional) Configures the number of seconds that a bundle link will wait for a hello message acknowledgment before resending the hello message.

The default value is 4 seconds.

Step 8 

frame-relay multilink retry number

Example:

Router(config-if)# frame-relay multilink retry 3

(Optional) Configures the maximum number of times that a bundle link will resend a hello message while waiting for an acknowledgment.

The default value is 2 tries.

Step 9 

end

Example:

Router(config-if)# end

Ends the configuration session and returns to privileged EXEC mode.

Step 10 

show frame-relay multilink

Example:

Router# show frame-relay multilink

(Optional) Displays the current Frame Relay multilink configuration.

Monitoring and Maintaining ASR1K Frame Relay-Multilink (MLFR-FRF.16)

SUMMARY STEPS

1. enable

2. debug frame-relay multilink [control [MFRnumber | Serial number]]

3. show frame-relay multilink [MFRnumber | Serial number] [detailed]

4. show interfaces MFRnumber

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

Enter your password if prompted.

Step 2 

debug frame-relay multilink [control [MFRnumber | Serial number]]

Example:

Router# debug frame-relay multilink control MFR1

(Optional) Displays debug messages for multilink Frame Relay bundles and bundle links.

Step 3 

show frame-relay multilink [MFRnumber | Serial number] [detailed]

Example:

Router# show frame-relay multilink MFR1 detailed

(Optional) Displays configuration information and statistics about multilink Frame Relay bundles and bundle links.

Step 4 

show interfaces MFRnumber

Example:

Router# show interfaces MFR1

(Optional) Displays information and packet statistics for the bundle interface.

Examples

The following is sample output from the show frame-relay multilink command. Because a particular bundle or bundle link is not specified, information for all bundles and bundle links is displayed.

Router# show frame-relay multilink 

Bundle: MFR1, State = down, class = A, fragmentation disabled
 BID = router1
 Bundle links:
  Serial3/1, HW state = Administratively down, link state = Down, LID = second-link
  Serial3/2, HW state = up, link state = Add_sent, LID = first-link

Bundle: MFR1, State = down, class = B, fragmentation disabled
 BID = router1
 Bundle links:
  Serial3/0, HW state = Administratively down, link state = Down, LID = third-link
  Serial3/1, HW state = Administratively down, link state = Down, LID = second-link
  Serial3/2, HW state = up, link state = Add_sent, LID = first-link

The following is sample output from the show frame-relay multilink command when a Frame Relay bundle is configured as bandwidth class C (threshold):

Router# show frame-relay multilink 

Bundle: MFR2, State = down, class = C (threshold 100), fragmentation disabled
 BID = router2
 Bundle links:
  Serial3/1, HW state = Administratively down, link state = Down, LID = cisco2
  Serial3/0, HW state = Administratively down, link state = Down, LID = cisco1

The following is sample output from the show frame-relay multilink command when the Serial number keyword and argument pair is specified. It displays information about the specified bundle link.

Router# show frame-relay multilink Serial 3/2

Bundle links:
  Serial3/2, HW state = up, link state = Add_sent, LID = first-link
  Bundle interface = MFR1,  BID = router1

The following is sample output from the show frame-relay multilink command when the Serial number keyword and argument pair and the detailed option is specified. Detailed information about the specified bundle links is displayed.

Router# show frame-relay multilink Serial 3/2 detail

Bundle links:

  Serial3/2, HW state = up, link state = Add_sent, LID = first-link
  Bundle interface = MFR1,  BID = router1
    Cause code = none, Ack timer = 6, Hello timer = 9,
    Max retry count = 3, Current count = 0,
    Peer LID = , RTT = 0 ms
    Statistics:
    Add_link sent = 110, Add_link rcv'd = 0,
    Add_link ack sent = 0, Add_link ack rcv'd = 0,
    Add_link rej sent = 0, Add_link rej rcv'd = 0,
    Remove_link sent = 0, Remove_link rcv'd = 0,
    Remove_link_ack sent = 0, Remove_link_ack rcv'd = 0,
    Hello sent = 0, Hello rcv'd = 0,
    Hello_ack sent = 0, Hello_ack rcv'd = 0,
    outgoing pak dropped = 0, incoming pak dropped = 0

Configuration Examples for ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Example: Configuring Multilink Frame Relay

Example: Configuring Variable Bandwidth Class Support

Example: Configuring Multilink Frame Relay

The following example shows the configuration of bundle "MFR1." Serial interfaces 3/0 and 3/2 are configured as bundle links:

interface MFR1
 no ip address
 frame-relay intf-type dce
 frame-relay multilink bid router1
!
interface MFR1.1 point-to-point
 ip address 10.0.0.1 255.255.255.0
 frame-relay interface-dlci 100

interface Serial3/0
 encapsulation frame-relay MFR1
 frame-relay multilink lid first-link
 frame-relay multilink hello 9
 frame-relay multilink retry 3
 frame-relay multilink ack 4

interface Serial3/2
 encapsulation frame-relay MFR1
 frame-relay multilink lid first-link
 frame-relay multilink hello 8
 frame-relay multilink ack 3
 frame-relay multilink retry 2

Example: Configuring Variable Bandwidth Class Support

The following example configures the Frame Relay bundle "MFR2" to use the class B (all links) criterion to be activated or deactivated:

interface MFR2
 frame-relay multilink bandwidth-class b
 frame-relay intf-type dce
 frame-relay multilink bid router2
 exit
interface MFR2.2 point-to-point
 ip address 10.1.1.10 255.255.255.0
 frame-relay interface-dlci 145
  end

Additional References

Related Documents

Related Topic
Document Title

Cisco IOS commands

Cisco IOS Master Commands List, All Releases

WAN commands

Cisco IOS Wide-Area Networking Command Reference

Frame Relay configuration

Configuring Frame Relay


Standards

Standard
Title

FRF.16.1

Multilink Frame Relay UNI/NNI Implementation Agreement, May 2002


MIBs

MIB
MIBs Link

None

To locate and download MIBs for selected platforms, Cisco software releases, and feature sets, use Cisco MIB Locator found at the following URL:

http://www.cisco.com/go/mibs


RFCs

RFC
Title

None


Technical Assistance

Description
Link

The Cisco Support and Documentation website provides online resources to download documentation, software, and tools. Use these resources to install and configure the software and to troubleshoot and resolve technical issues with Cisco products and technologies. Access to most tools on the Cisco Support and Documentation website requires a Cisco.com user ID and password.

http://www.cisco.com/cisco/web/support/index.html


Feature Information for ASR1K Frame Relay-Multilink (MLFR-FRF.16)

Table 2 lists the release history for this feature.

Use Cisco Feature Navigator to find information about platform support and software image support. Cisco Feature Navigator enables you to determine which software images support a specific software release, feature set, or platform. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.


Note Table 2 lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.


Table 2 Feature Information for Multilink-Frame Relay (MLFR-FRF.16) 

Feature Name
Releases
Feature Information

ASR1K Frame Relay - Multilink (MLFR-FRF.16)

Cisco IOS XE Release 3.4S

The ASR1K Frame Relay-Multilink (MLFR-FRF.16) feature is based on the Frame Relay Forum Multilink Frame Relay UNI/NNI Implementation Agreement (FRF.16.1) on the Aggregation Service Routers.

The following sections provide information about this feature:

Information About ASR1K Frame Relay-Multilink (MLFR-FRF.16)

How to Enable ASR1K Frame Relay-Multilink (MLFR-FRF.16)

The following commands were introduced or modified: debug frame-relay multilink, encapsulation frame-relay mfr, frame-relay multilink ack, frame-relay multilink bandwidth-class, frame-relay multilink bid, frame-relay multilink hello, frame-relay multilink lid, frame-relay multilink retry, interface mfr, show frame-relay multilink.


Glossary

BID—bundle identification. The BID is the name used to identify the bundle. The BID can be assigned, or the default can be used.

BL_ACTIVATE—A message that controls the addition of a bundle link to a Frame Relay bundle.

BL_DEACTIVATE—A message that controls the removal a bundle link from a Frame Relay bundle.

bundle—A logical grouping of one or more physical interfaces using the formats and procedures of multilink Frame Relay. A bundle emulates a physical interface to the Frame Relay data link layer. The bundle is also referred to as the MFR interface.

bundle link—An individual physical interface that is a member of a bundle.

DLCI—data-link connection identifier. A value that identifies a permanent virtual circuit (PVC) in a Frame Relay network.

HELLO message—A message that notifies a peer endpoint that the local endpoint is in the operational state (up).

HELLO_ACK—A message that notifies a peer endpoint that a hello message has been received.

LID—link identification. The LID is the name used to identify a bundle link. The LID can be assigned, or the default can be used.

LMI—Local Management Interface. A set of enhancements to the basic Frame Relay specification. LMI includes support for a keepalive mechanism, which verifies that data is flowing; a multicast mechanism, which provides the network server with its local DLCI and the multicast DLCI; global addressing, which gives DLCIs global rather than local significance in Frame Relay networks; and a status mechanism, which provides an ongoing status report on the DLCIs known to the switch.

NNI—Network-to-Network Interface. The interface between two Frame Relay devices that are both located in a private network or both located in a public network.

PH_ACTIVATE—A message that indicates that the Frame Relay bundle is up.

PH_DEACTIVATE—A message that indicates that the Frame Relay bundle is down.

UNI—User-Network Interface. The interface between a Frame Relay device in a public network and a Frame Relay device in a private network.