Netopia Router PN Series - Manual (Page 252)

B-16 Reference Guide
Broadcasts
As mentioned earlier, binary IP host or subnet addresses composed
entirely of ones or zeros are reserved for broadcasting. A broadcast
packet is a packet that is to be delivered to every host on the
network, if both the host address and the subnet address are all ones
or all zeros, or to every host on the subnetwork, if the host address is
all ones or all zeros but the subnet address is a combination or zeros
and ones. Instead of making many copies of the packet, individually
addressed to different hosts, all the host machines know to pay
attention to broadcast packets, as well as to packets addressed to
their specific individual host addresses. Depending on the age and
type of IP equipment you use, broadcasts will be addressed using
either all zeros or all ones, but not both. If your network requires zeros
broadcasting, you must configure this through SNMP.
Packet header types
As previously mentioned, IP works with other protocols to allow
communication over IP networks. When IP is used on an Ethernet
network, IP works with the Ethernet or 802.3 framing standards,
among other protocols. These two protocols specify two different
ways to organize the very first signals in the sequence of electrical
signals that make up an IP packet travelling over Ethernet. When you
install and configure the Netopia Router to be an AppleTalk–IP
gateway, you must specify whether it should use Ethernet or 802.3. If
you do not know which to use, see the documentation provided with
your IP computers, or talk with your IP network manager or the vendor
of your IP equipment. By default, the Netopia Router uses Ethernet
packet headers for IP traffic. If your network requires 802.3 IP
framing, you must configure this through SNMP.