Configuring Frame-Relay Multi-Point Without Sub-Interface

Table of Contents

1. Introduction

2. Understanding Frame-Relay Multi-Point Configuration

3. Configuration Steps

Step 1: Selecting the Interface

Step 2: Assigning IP Address

Step 3: Setting Encapsulation

Step 4: Configuring LMI Type

Step 5: Mapping Local IP Address

Step 6: Mapping Remote IP Addresses

4. Sample Configuration

5. Additional Features

6. Best Practices

7. Conclusion

1. Introduction

Frame-Relay is a widely-used WAN protocol that facilitates efficient data transmission across wide area networks (WANs). This guide focuses on configuring a Multi-Point Frame-Relay connection without using sub-interfaces.

2. Understanding Frame-Relay Multi-Point Configuration

A Multi-Point Frame-Relay configuration involves one IP subnet with multiple connections (DLCIs) on a single physical interface. This setup is ideal for environments where multiple remote sites connect to a central hub.

3. Configuration Steps

Step 1: Selecting the Interface

First, select the appropriate serial interface on the router.

R1(config)# interface serial 0/0/0

Step 2: Assigning IP Address

Assign an IP address to the serial interface. A subnet larger than /30 is typically used for Multi-Point configurations.

R1(config-if)# ip address 192.168.5.1 255.255.255.248

Step 3: Setting Encapsulation

Set the encapsulation type to Frame-Relay. 'Cisco' is the default, but 'ietf' can be specified for interoperability with non-Cisco devices.

R1(config-if)# encapsulation frame-relay

Step 4: Configuring LMI Type

The Local Management Interface (LMI) type can be configured based on the network requirements. 'Cisco' is the default, but 'ansi' or 'q933a' can also be specified.

R1(config-if)# frame-relay lmi-type [ansi, q933a, cisco]

Step 5: Mapping Local IP Address

Map the local IP address to a valid DLCI to allow local pings.

R1(config-if)# frame-relay map ip 192.168.5.1 752

Step 6: Mapping Remote IP Addresses

Map the remote IP addresses to their respective DLCIs. The 'broadcast' keyword allows broadcast and multicast traffic. Specify 'ietf' if using IETF encapsulation.

R1(config-if)# frame-relay map ip 192.168.5.2 752 broadcast [ietf, cisco]

R1(config-if)# frame-relay map ip 192.168.5.3 339 broadcast [ietf, cisco]

4. Sample Configuration

Below is the complete configuration example for Router R1 with a Multi-Point Frame-Relay connection without using sub-interfaces:

R1(config)# interface serial 0/0/0

R1(config-if)# ip address 192.168.5.1 255.255.255.248

R1(config-if)# encapsulation frame-relay

R1(config-if)# frame-relay lmi-type ansi

R1(config-if)# frame-relay map ip 192.168.5.1 752

R1(config-if)# frame-relay map ip 192.168.5.2 752 broadcast ietf

R1(config-if)# frame-relay map ip 192.168.5.3 339 broadcast ietf

In this example:

• interface serial 0/0/0: Specifies the serial interface.
• ip address 192.168.5.1 255.255.255.248: Assigns IP address with a larger subnet for Multi-Point configuration.
• encapsulation frame-relay: Sets Frame-Relay encapsulation.
• frame-relay lmi-type ansi: Configures the LMI type to ANSI.
• frame-relay map ip 192.168.5.1 752: Maps the local IP address to DLCI 752.
• frame-relay map ip 192.168.5.2 752 broadcast ietf: Maps the remote IP address 192.168.5.2 to DLCI 752 with broadcast and IETF encapsulation.
• frame-relay map ip 192.168.5.3 339 broadcast ietf: Maps the remote IP address 192.168.5.3 to DLCI 339 with broadcast and IETF encapsulation.

5. Additional Features

Traffic Shaping: Implement traffic shaping to manage bandwidth and ensure Quality of Service (QoS).

Inverse ARP: Utilize Inverse ARP to automatically map remote IP addresses to local DLCIs, simplifying the configuration.

6. Best Practices

Consistent Configuration: Ensure consistency across all router configurations to avoid connectivity issues.

Monitor LMI: Regularly monitor the LMI status to ensure the health of the Frame-Relay network.

Secure Frame-Relay Links: Use access control lists (ACLs) and other security measures to protect Frame-Relay links from unauthorized access.

Documentation: Maintain detailed documentation of Frame-Relay configurations for troubleshooting and maintenance.

7. Conclusion

Configuring Frame-Relay for a Multi-Point connection without sub-interfaces is straightforward and efficient for networks requiring multiple connections on a single physical interface. By following this guide, you can effectively set up and manage Multi-Point Frame-Relay connections in your network.

Feel free to reach out with any questions or comments about this configuration process!