Esa Entry - Nortel DMS-100 Series Maintenance Manual

5-2 ESA maintenance overview
Figure 5-1 Star Hub ESA capability diagram
Host
LTC, LGC
or RCC2
Star
Hub
Remote
When the Star Hub is in ESA mode, the diagram in this figure is not accurate.
In ESA mode, the ESA software that is in the RCP acts as the host peripheral
module (PM). In this mode, the host PM is the LTC. This figure does not
describe the hardware configuration from the view of the MAP terminal. The
Star Hub functions separately from the host.

ESA entry

The Star Hub enters the ESA mode when the Star Hub determines that
communication with the host site cannot occur. The two conditions that cause
the Star Hub to enter ESA are
•
•
When the Star Hub determines the ESA mode is required, the Star Hub
switches the C-side links from the host to the RCP processor. The RCP
processor detects the switch of links. The software begins an ESA-entry. The
type of failure condition determines the time between loss of communication
and ESA mode.
297-8353-550 Standard 05.01 March 2001
To host SuperNode
0 1
Unit 0
0 2
Unit 0
0 2
RCP unit 0
ESA software
UMP 0
communication links that cannot be used
looparound message audit failure
2 3
Unit 1
1 3
Unit 1
1 3
RCP unit 1
ESA software
UMP 1
(up to 32 DS30 links)
(up to 16 DS-1
links)
Message links