Instruction manual

page 47
Reference Manual
Networked PIP Series
Some of the features of HiQnet and TCP/IQ include:
• Ability to quickly discover all components connected to the network.
• Synchronization of multiple control points on a network.
• Components on different Local Area Networks (LANs) through the use of an IP router.
• Component firmware upgrades via the network.
Ethernet Networks are established through the use of either a hub or a switch. These
devices are centralized in the network and transfer the Ethernet data from point to point.
Ethernet data is transferred in data packets that have addresses coded into their structure.
Hubs and switches decipher these addresses and route the data packets to the appropriate
component. Hubs do this by taking packets from any port and sending them out all other
ports. Switches, on the other hand, are more intelligent and examine each packet’s address,
sending that packet only to the addressed component. This results in a much more efficient
data flow.
Communications between networks is allowed, but requires the use of a special piece of
equipment called an IP Router. The router acts as a Gateway to allow this communication to
exist. Any data traffic that is to go to the other network is routed through the IP Router. The
CobraNet data is held behind but IP data goes through.
Each IQ Component has three identifiers that are used in theTCP/IQ or HiQnet system:
• Media Access Control (MAC) Address
• Internet Protocol (IP) Address
• IQ or HiQnet Address
Let’s explain each identifier.
Media Access Control (MAC) Address: This is a physical address that specifies a
specific physical network component. This address is predefined during manufacture and
cannot be modified. No two network components have the same MAC address and each
component is uniquely identified by its MAC address. This 48 bit address is located on the
outside of every IQ component and is shown in hexadecimal format as 6 two-byte octets
such as:
00-0A-40-00-DC-2F
Internet Protocol (IP) Address: The IP address of a component is assigned during the
setup of the network and identifies the IQ component to a larger audience. Because the
MAC address is limited to a single physical LAN, communications between LANs is impos-
sible solely through the use of the MAC address. The IP address allows components and
controllers on other networks to communicate with each other through the use of an IP
Router as shown in Figure 6.4.
136763-7_4-08_networked_pip-series_reference_manual.fm Page 47 Monday, March 17, 2008 11:17 AM