Operation Manual; DBC Network Bridge ; Media Access Control (MAC) Address: - Page 77

DBC Network Bridge 

Operation Manual

page 77

Figure 8.2  Multiple Network Communication Via an IP Router

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 the TCP/IQ 
system:

•

 Media Access Control (MAC) Address

•

 Internet Protocol (IP) Address

•

 IQ 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 for-
mat 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 compo-
nent to a larger audience. Because the MAC address is limited to a sin-
gle physical LAN, communications between LANs is impossible solely 
through the use of the MAC address. The IP address allows compo-
nents and controllers on other networks to communicate with each 
other through the use of an IP Router as shown in Figure 8.2.

This allows the network designer to isolate network traffic from each 
other. For example, when using wireless devices to control IQ compo-
nents, the bandwidth limitation of wireless devices will not allow them 
to reside on the same network with CobraNet. As a result, the use of an 
IP router and a separate network allows the wireless controllers to 
access the IQ components through the router using IP addressing. The 
IP address appears as four numbers (0-255) separated by periods, such 
as: 

126.126.0.1

IQ Address: 

TCP/IQ components will be addressed with a unique 

number from 1 to 65,535 and are assigned within the IQ software. A 
separate utility is then run which queries the network and establishes 
what IQ components and their associated MAC addresses are present. 
An IP Address and IQ Address can then be assigned to each IQ compo-
nent. 

PDA

Wireless

Access Point

IP Router

Computer

100Mb Switch

Wireless

Devices

Computer

100Mb Switch