User`s guide

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Q
Quality of Service The Quality of Service (QoS) object allows the data traffic of individual
applications or interfaces to be managed. The performance of a particular
application can be guaranteed by raising the priority of its dataflow, relative
to the other applications.
R
RADIUS Remote Authentication Dial In User Service (RADIUS) is an Authentication,
Authorization, and Accounting (AAA) protocol for controlling access to
network resources. RADIUS is commonly used by ISPs and corporations
managing access to Internet or internal networks across an array of access
technologies including modem, DSL, wireless, and VPNs.
RAID Redundant Array of Inexpensive Disks.
RDMA Remote Direct Memory Access. One of the key problems with server I/O is
the CPU overhead associated with data movement between memory and
I/O devices, such as LAN and SAN interfaces. InfiniBand solves this
problem by using RDMA to offload data movement from the server CPU to
the InfiniBand HCA. Using RDMA, the sending device either reads data
from or writes data to the target devices’ user space memory, thereby
avoiding CPU interrupts and multiple data copies on the memory bus. This
approach enables RDMA to significantly reduce the CPU overhead
associated with data movement between nodes.
Role One of 5 fixed-privilege levels that a user may be assigned (such as,
Operators, Administrators, or Storage).
S
SAN Fibre Channel Storage Area Network. A SAN is a network of storage and
system components, all communicating on a fibre-channel network, that can
be used to consolidate and share storage, provide high-performance links to
data devices, add redundant links to storage systems, speed up data backup,
and support high-availability clustering systems. The advent of SANs has
been driven by today’s insatiable appetite for storage. See www.snia.org for
more background information.