Net Insight Nimbra 300 Series, User Manual

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Control Network Element Manager User’s Manual Nimbra OneSerie
©2006 Net Insight AB, All rights reserved
Note:
Note! that the DLE segment is a logical segment. The physical
topology exists only on the DTM level.
IP and routing
Each node that is connected to the DLE segment has, an virtual IP interface
assignied, allowing the node to communicate with other nodes on the segment
using IP. A gateway routes the IP packets to and from the segment. This means
that each segment has its own IP network address. Routing can be to other
networks, i.e. DLE segments, or to an out-band IP network.
Routing will load the Control Module CPU of the gateway node. The number
of packets that can be routed will therefore be limited by the capacity of the
Control Module.
DLE clients
Each virtual Ethernet interface is implemented by the DLE client, one client
per virtual interface. When Ethernet packets are sent from one node to another
within the segment, the client will establish a channel to the remote node. The
remote node would establish a return channel for any reply. This means that
from each node, there will be a channel established to every other node in the
segment to which packets have been sent. To reduce the number of channels in
a segment, channels can be torn down automatically or manually when they are
no longer used. It is possible to have multiple clients on a single node,
implementing multiple virtual Ethernet interfaces.
Gateway
E
C
D
F
A
B
Figure 45. A DLE segment with channels between DLE clients
In Figure 45, it is assumed that all nodes has communicated via the gateway.
So the gateway (A) has channels connected to and from all the nodes.
Communications has also occurred between node (E) and (F) resulting in a
channels between these two nodes. Channels that are not used has been torn
down, hence no channels exists between any other nodes.
Note: Figure 45, shows the DTM channels. The physical topology is
not presented.