Rockwell Automation 1734-AENT POINT I/O EtherNet/IP Adapter Module - Manual (Page 9)

Publication 1734-UM011D-EN-P - May 2011
Preface ix
Hardware address Each Ethernet device has a unique hardware address (sometimes
called a MAC address) that is 48 bits. The address appears as six
digits separated by colons (such as, xx:xx:xx:xx:xx:xx). Each digit has a
value between 0 and 255 (0x00 to 0xFF). This address is assigned in
the hardware and cannot be changed. The hardware address is
required to identify the device if you are using a BOOTP utility.
Host name The host name is the unique name for a computer within its domain.
It's always the first element of a full name, and, with its domain and
top-level domain suffix, creates the unique name of that computer on
the Internet. For example, let's say a trading website is
www.trading.com. The host name is www, which is not unique on
the web, but is unique within the trading domain.
The host name can also refer to the fully qualified domain name
(FQDN), or in this example, www.trading.com. Both naming methods
seem to be used interchangeably in various documents. For the
purposes of this document, the host name will refer to the FQDN, or
as in this example, www.trading.com.
Hub A central connecting device that joins devices together in a star
configuration. Hubs are generally not suitable for use in I/O control
systems, since they are time-critical applications that cannot tolerate
lost packets.
Implicit messaging Real-time messaging of I/O data.
IP
Internet protocol that provides the routing mechanism for messages.
All messages contain not only the address of the destination station,
but the address of a destination network, which allows messages to
be sent to multiple networks within an organization or around the
world.
IP address A 32-bit identification number for each node on an Internet Protocol
network. These addresses are represented as four sets of 8-bit
numbers (numbers from 0 to 255), with decimals between them. Each
node on the network must have a unique IP address.
Latency The time between initiating a request for data and the beginning of
the actual data transfer.
Multicast In the CIP producer/consumer model, one producer multicasts
(broadcasts) the data once to all the consumers.
Producer The source of information in the CIP networking model. See CIP.
Rack-optimized A physical and logical collection of application modules.
Subnet mask An extension of the IP address that allows a site to use a single net
ID for multiple networks.
Switch A network device that cross connects devices or network segments.
A switch provides each sender/receiver the full network bandwidth
(2x in full duplex mode), reduces collisions, and increases
determinism.
TCP The transport control protocol is a more reliable but slower transport
protocol than UDP. It is used for explicit (not time critical) messaging
in EtherNet/IP.
Term Definition