ServerNet Cluster 6780 Planning and Installation Guide (G06.24+, H06.03+)

Glossary
ServerNet Cluster 6780 Planning and Installation Guide—527301-004
Glossary-12
HP NonStop ServerNet Switch (model 6780)
uninterruptible power supply (UPS), and AC transfer switch, and it can be packaged in
a switch enclosure or in a 19-inch rack. See also HP NonStop ServerNet Switch
(model 6780).
HP NonStop ServerNet Switch (model 6780). The cluster switch used in the layered
topology. The 6780 switch consists of a switch logic board, a midplane, plug-in cards,
power supplies, and fans. See also HP NonStop Cluster Switch (model 6770).
IBC. See in-band control (IBC).
IEEE 802.3 protocol. Institute of Electrical and Electronics Engineers (IEEE) standard
defining the hardware layer and transport layer of (a variant of) Ethernet. The
maximum segment length is 500 meters and the maximum total length is 2.5
kilometers. The maximum number of hosts is 1024. The maximum packet size is 1518
bytes.
in-band control (IBC). A symbol-based communications protocol for communicating
management information across a ServerNet link without interfering with any
application traffic in the network. In ServerNet II, IBC traffic is via standard ServerNet
packets. ServerNet I used the Illegal Symbol variation of IBC. This technique uses a
subset of the available symbols to convey control information from one node to
another. The symbol subset chosen is from the group of symbols that are not for
passing data; these symbols are usually considered illegal or unused.
incident report. A report sent by the OSM software to the OSM Notification Director If
remote notification (dial-out) is configured, the OSM Notification Director forwards
incident reports to a service provider. The three types of incident reports are problem
incident reports, periodic incident reports, and software configuration incident reports.
input/output process (IOP). A running program (part of the HP NonStop™ operating
system) that manages the I/O functions for one or more ServerNet addressable
controllers (SACs) of the same type.
internal routing. The routing of packets within a node. See also external routing.
internal ServerNet fabric. The X or Y fabric that links ServerNet devices within a node.
See also external ServerNet fabrics.
Internet protocol (IP). A data communications protocol that handles the routing of data
through a network, which typically consists of many different subnetworks. IP is
connectionless; it routes data from a source address to a destination address. See also
IP address.
interprocessor communication (IPC). The exchange of messages between processors in
the same system or node.
I/O enclosure. A NonStop S-series system enclosure containing one module, which
includes ServerNet adapters, disk drives, components related to the ServerNet fabrics,
and components related to electrical power and cooling for the enclosure. An I/O