Cabletron Systems DMS-100 - Manual (Page 42)

42 Chapter 1: Introduction to the EIU
297-8991-910 Standard 03.01 August 1999
— the EIU state
• During normal operation, the default EIU routes all messages to the CM.
If there is a problem with the default EIU or its links, the following occurs:
— the default EIU advertises to the network that it is no longer available
(or in the event of a LAN-side link failure, the neighboring routers
cannot reach the default EIU)
— another provisioned EIU advertises that it is the router (net hop) to the
SuperNode-side subnet and the CM
• During normal operations, if there is a problem with the non-default EIU
or its links, there is no impact on service unless the default EIU
experiences problems, in which case the SuperNode subnet is isolated
from the LAN-side subnet until one of more EIUs are brought back into
service.
Applications running on the EIUs must have sparing defined at the application
level.
Billing
EIUs do not directly affect billing functions.
Service orders
The EIU does not affect service order functions.
User interface characteristics
The EIU uses the existing peripheral user interface (UI) based on the DMS
MAPCI. The MAPCI includes additions to the PM level of the MAP display
to include the new hardware components. Figure 10 shows the hierarchical
relationship for the MAP levels used for the components.
Figure 10 MAP display level hierarchy
PM level
EIU level EXND level
(LAN devices)
Existing
peripheral
modules