Broadcasts; Packet Header Types - Netopia 435 Reference Manual

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 ISDN 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 ISDN Router uses Ethernet packet headers for IP traffic. If
your network requires 802.3 IP framing, you must configure this
through SNMP.