Medical Archive Solutions User Guide

HPMA User Guide
56
HP Medical Archive
ADC—Administrative Domain Controller
The Administrative Domain Controller (ADC) authenticates the grid
nodes and their connections with each other. For two nodes to connect,
the ADC must have certificates for both. The ADC maintains the certif-
icates and synchronizes this information with the other ADCs in the
grid.
In general, all system nodes maintain a connection to at least one ADC.
This ensures that the nodes are always accessing the latest certificates
(occasionally updated or revoked). When nodes connect they cache
other nodes’ certificates, enabling systems to continue functioning
with known nodes even when an ADC is unavailable. New nodes can
only establish connections via an ADC.
The connection of each node lets the ADC gather topology informa-
tion. This node information includes the CPU load, the amount of
available disk space (if it has storage), the supported services, and the
node’s group ID (location). The grid’s LDRs, CMSs, and CLBs ask the
ADC for topology information through topology queries. The ADC
responds to each query with the latest information received from the
grid.
Group IDs are in the form of 10X00Y, where X and Y are pre-assigned
based on the site and cabinet number. For example, cabinet B-3 would
have a Group ID of 102003. These are used in placing replications
under business rules, to permit the grid to disperse data in the most
robust and efficient manner possible within the available topology.
ADC Attributes
The ADC supports the common set of service attributes. These
common service attributes appear on the Overview tab for the service.
Table 10: ADC Service Attributes
Attribute Type / Units Description
C T Alarm
ADC State Enumerated
Text
Current state of the service:
2=Online
1 = Standby
0=Offline
ADCE