Bradley Smoker 1734-AENT Manual De Usuario

Descargar
Página de 170
Publication 1734-UM011C-EN-P - January 2006
6      Preface   
consumer
A destination device in the CIP networking model. See CIP.
CSMA/CD
Carrier sense multiple access/collision detection is the access 
method used in Ethernet. When a device wants to gain access to the 
network, it checks to see if the network is quiet (senses the carrier). 
If it is not, it waits a random amount of time before retrying. If the 
network is quiet and two devices access the line at exactly the same 
time, their signals collide. When the collision is detected, they both 
back off and each waits a random amount of time before retrying.
Determinism
The ability to predict when information will be delivered. Important in 
time-critical applications.
DHCP
The dynamic host configuration protocol is an Internet protocol, 
similar to BootP, for automating the configuration of computers that 
use TCP/IP. DHCP can be used to automatically assign IP addresses, 
to deliver IP stack configuration parameters, such as the subnet mask 
and default router, and to provide other configuration information, 
such as the addresses for printer, time, and news servers.
The 1734-AENT factory default is DHCP enabled. When you apply 
power, the module sends a message containing its hardware address 
to any DHCP server on the network. The server(s) replies by sending a 
message with an appropriate IP address for the adapter. The adapter 
responds by acknowledging to a server that it will use the offered IP 
address.
DNS
The domain name system is a hierarchical, distributed method of 
organizing the name space of the Internet. The DNS administratively 
groups hosts into a hierarchy of authority that allows addressing and 
other information to be widely distributed and maintained. A big 
advantage to the DNS is that using it eliminates dependence on a 
centrally-maintained file that maps host names to addresses.
Ethernet
A physical layer standard using carrier sense multiple access with 
collision detection (CSMA/CD) methods.
EtherNet/IP
Ethernet industrial protocol applies a common application layer (CIP) 
over Ethernet by encapsulating messages in TCP/UDP/IP.
Ethernet network
A local area network designed for the high-speed exchange of 
information between computers and related devices.
Explicit messaging
Non-time critical messaging used for device configuration and data 
collection, such as downloading programs or peer-to-peer messaging 
between two PLC units.
Full duplex
A mode of communication that allows a device to send and receive 
information at the same time, effectively doubling the bandwidth.
Fully qualified
domain name
A fully qualified domain name (FQDN) is a domain name that includes 
all higher level domains relevant to the entity named. If you think of 
the DNS as a tree-structure with each node having its own label, a 
fully qualified domain name for a specific node would be its label 
followed by the labels of all the other nodes between it and the root 
of the tree. For example, for a host, a FQDN would include the string 
that identifies the particular host, plus all domains of which the host 
is a part, up to and including the top-level domain (the root domain is 
always null). For example, PARIS.NISC.SRI.COM is a fully qualified 
domain name for the host at 192.33.33.109.
This Term
Means