ADTRAN 1000R Series - Manual (Page 753)

Command Reference Guide ATM Sub-Interface Config Command Set
61200510L1-35E Copyright © 2005 ADTRAN 753
ip helper-address <address>
Use the ip helper-address command to configure the AOS to forward User Datagram Protocol (UDP)
broadcast packets received on the interface. Use the no form of this command to disable forwarding
packets.
Syntax Description
<address> Specifies the destination IP address (in dotted decimal notation) for the forwarded
UDP packets.
Default Values
By default, broadcast UDP packets are not forwarded.
Applicable Platforms
This command applies to the NetVanta 300, 1000R, 3000, and 4000 Series units.
Command History
Release 1.1 Command was introduced.
Release 8.1 ATM sub-interface was added.
Functional Notes
When used in conjunction with the ip forward-protocol command, the ip helper-address feature allows
you to customize which broadcast packets are forwarded.
To implement the helper address feature, assign an address(es) (specifying the device that needs to
receive the broadcast traffic) to the interface closest to the host that transmits the broadcast packets.
When broadcast packets (of the specified type forwarded using the ip forward-protocol command) are
received on the interface, they will be forwarded to the device that needs the information.
Only packets meeting the following criteria are considered eligible by the ip helper-address feature:
1. The packet IP protocol is UDP.
2. Any UDP port specified using the ip forward-protocol command.
3. The media access control (MAC) address of the frame is an all-ones broadcast address (ffff.ffff.ffff).
4. The destination IP address is broadcast defined by all ones (255.255.255.255) or a subnet broadcast
(for example, 192.33.4.251 for the 192.33.4.248/30 subnet).
The ip helper command must be used in conjunction with the ip forward-protocol
command to configure the AOS to forward UDP broadcast packets. See ip
forward-protocol udp <port number>
on page 425 for more information.