IBM TotalStorage DS300 Best Practices Manual page 655

NL_Port node loop port A node port that supports
arbitrated loop devices.
O
Open system A system whose characteristics
comply with standards made available throughout
the industry, and therefore can be connected to
other systems that comply with the same standards.
P
Peer-to-Peer remote copy A hardware based
remote copy option that provides a synchronous
volume copy across storage subsystems for disaster
recovery, device migration, and workload migration.
Point-to-point topology It consists of a single
connection between two nodes. All the bandwidth is
dedicated for these two nodes.
Port An endpoint for communication between
applications, generally referring to a logical
connection. A port provides queues for sending and
receiving data. Each port has a port number for
identification. When the port number is combined
with an Internet address, it is called a socket
address.
Port zoning In Fibre Channel environments, port
zoning is the grouping together of multiple ports to
form a virtual private storage network. Ports that are
members of a group or zone can communicate with
each other but are isolated from ports in other zones.
See also LUN masking and subsystem masking.
POST In HTTP, a parameter on the METHOD
attribute of the FORM tag that specifies that a
browser will send form data to a server in an HTTP
transaction separate from that of the associated
URL.
PPRC See Peer-to-Peer remote copy.
Protocol The set of rules governing the operation
of functional units of a communication system if
communication is to take place. Protocols can
determine low-level details of machine-to-machine
interfaces, such as the order in which bits from a
byte are sent. They can also determine high-level
exchanges between application programs, such as
file transfer.
R
RAID Redundant array of inexpensive or
independent disks. A method of configuring multiple
disk drives in a storage subsystem for high
availability and high performance.
0 Level 0 RAID support - Striping, no
RAID
redundancy.
1 Level 1 RAID support - mirroring,
RAID
complete redundancy.
5 Level 5 RAID support, Striping with
RAID
parity.
RDAC See Redundant Disk Array Controller.
Redundant Disk Array Controller Controller
failover facility provided for some operating systems
with the FAStT product line.
Remote volume mirroring A hardware based
remote copy option that provides a synchronous
volume copy with the FAStT product line.
Router (1) A device that can decide which of
several paths network traffic will follow based on
some optimal metric. Routers forward packets from
one network to another based on network-layer
information. (2) A dedicated computer hardware
and/or software package which manages the
connection between two or more networks. See also
Bridge, Bridge/Router.
RVM See Remote volume mirroring.
S
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Glossary