September 2011
11
V1.44
Copyright © 2011 Adept Systems, Inc. and Control Network Solutions Ltd All Rights Reserved.
networks is show in Figures 1.6 and 1.7.
1.5. IP Addressing Modes
The eNodeIV device uses one of two forms of IP addressing: unicast and multicast. Multicast
currently only works when in manual mode.
The advantage of multicast is that for networks with multiple Gateways (especially in flood
mode), multicast may be more efficient. The disadvantage of multicast is that some internet
routers do not support it. Multicast mode can reduce the IP traffic relative to unicast when
there are a large number of 852 devices in the channel. Up to 255 devices per IP domain are
supported with multicast. Some older IP routers do not support multicast and therefore you
will not be able to route 852 packets across a unicast only router with multicast addressing. IP
router support for Multicast is not a concern when all the 852 devices share the same subnet.
The following figures illustrate the differences between multicast and unicast.
Fig.1.8: Unicast
Fig.1.9: Multicast
