Chapter 4: Configuration Overview
61200350L1-1 Router Option Module User Manual
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UDP Relay/UDP Relay List
Up to four relay destination servers can be specified in this list.
UDP Relay List/Relay Address
Write security: 3; Read security: 5
This is the IP address of the server that will receive the relay packet.
UDP Relay List/UDP Port Type
Write security: 3; Read security: 5
Standard (def)
The following standard UDP protocols are relayed when set:
• DHCP, TFTP, DNS,
• NTP (NetworkTime Protocol, port 123). NBNS (NetBIOS Name
Server, port 137), NBDG (NetBIOS Datagram, port 138),
• BootP.
Specified
• When set, the UDP port (1 to 65535) can be specified in the UDP
Port columns (up to a maximum of three per server).
UDP Relay List/UDP Port 1, UDP Port 2, UDP Port 3
Write security: 3; Read security: 5
UDP Port 1, UDP Port 2, and UDP Port 3 are used for specifying
UDP ports to be relayed. These fields only apply when UDP Port
Type is set to Specified.
IP/Proxy ARP
Write security: 4; Read security: 5
This feature allows the network portion of a group of addresses to
be shared between several physical network segments. The ARP
protocol itself provides a way for devices to create a mapping be-
tween physical (i.e., Ethernet) addresses and logical IP addresses.
Proxy ARP makes use of this mapping feature by instructing a rout-
er to answer ARP requests as a “proxy” for the IP addresses behind
one of its ports. The device which sent the ARP request will then
correctly assume that it can reach the requested IP address by send-
ing packets to the physical address that was returned to it. This tech-
nique effectively hides the fact that a network has been (further)
subnetted.
