HP Fabric Clustering System HP-UX Administrator's Guide, March 2008

IETF Internet Engineering Task Force (IETF) is a large international community of network designers,
operators, vendors, and researchers guiding the evolution of Internet architecture. See
http://www.ietf.org/overview.html.
IOC An I/O Controller (IOC) and Target Channel Adapter (TCA) are the parts of an I/O unit. IOCs
provide I/O services and TCAs (Target Channel Adapter) provide the transport services. The
I/O interface of the TCA is implemented by an I/O Controller.
IP Internet Protocol. A layer-3 protocol (transport) that uses a “best effort” approach to delivering
datagrams across networks.
IPoIB Internet Protocol over InfiniBand.
IT-API Interconnect Transport API. A user API for RDMA-capable transports including InfiniBand.
kernel The kernel is loaded into RAM when the system boots, and contains many critical procedures
that are needed for the system to operate. The essential shape and capabilities of the system
are determined by the kernel, which can also be referred to as the Operating System (OS).
LID Local IDentifier.
MAC The Media Access Control (MAC) address is a unique hardware number. On an Ethernet LAN,
it is the same number as your Ethernet address. When a host is connected to the Internet, a
correspondence table relates the IP address to your computer's physical (MAC) address on the
LAN. The MAC address is used by the Media Access Control sublayer of the Data-Link Layer
(DLC) layer of telecommunication protocol. There is a different MAC sublayer for each physical
device type. The other sublayer level in the DLC layer is the Logical Link Control sublayer.
MAD MAnagement Datagram.
MCAST Multicast message forwarding method that simultaneously transmits messages to multiple
ports on a fabric.
MIB The Management Information Base (MIB) defines the logical and physical characteristics of a
system. The “objects” in a MIB determine SNMP agent characteristics.
MPI Message Passing Interface (MPI) is used in computing clusters to provide high-speed and
scalable networks. A widely used set of standards for message passing that emphasize portability
and ease-of-use; common in High Performance Computing (HPC) applications.
NIC Network Interface Card.
NTP Network Time Protocol (NTP) synchronizes the clocks of networked computer systems. It
synchronizes system clocks to Universal Time (UTC) for millisecond and sub-millisecond
accuracy.
OSI Open System Interconnection.
OSPF Open Shortest Path First (OSPF) is a router protocol preferred in larger autonomous system
networks over the Routing Information Protocol (RIP). (RIP is a legacy protocol generally
running on older corporate networks.)
Protocol Stack A layered set of protocols that work together to provide a set of network functions. Each
intermediate protocol layer uses the layer below it to provide a service to the layer above.
QoS Quality of Service.
RARP Reverse Address Resolution Protocol (RARP) allows a LAN system to query a gateway server
for its IP address. The gateway server uses the MAC address of the requestor to locate the IP
address in the ARP table and returns the IP address to the requestor. This is typically used to
setup new systems.
RDMA Remote Direct Memory Access (RDMA) allows a network adapter, with the remote application’s
permission, to move data into and out of the application’s buffers. It is typically used by Fibre
Channel devices for block storage transfers, clustering applications, and InfiniBand.
RED Random Early Detection (RED) is an algorithm to monitor traffic load at points in the network
and stochastically discard packets as network congestion increases.
RIP Routing Information Protocol.
Service Level Used for Quality of Service (QoS), a Service Level (SL) specifies the desired service level desired
within a subnet. Service Levels are mapped to Virtual Lane.
224 Glossary