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Chapter 9: Glossary
Network Storage System (NSS) Administrator Guide
Chapter
9
(such as printers, and NAS) on a local network, in a intranet or on the Internet without knowing the
specific domain where they reside. A single LDAP directory can be mirrored on multiple servers that
can be periodically synchronized.
Link Aggregation Group:
(LAG) A computer networking term used to describe using multiple
Ethernet network cables/ports in parallel to increase the link speed beyond the limits of any one
single cable or port. Other terms for this also include "ethernet trunk", "NIC teaming", "port
teaming", "port trunking", "NIC bonding" and "link aggregate group" (LAG), and is based on a
networking standard known as "IEEE 802.3ad".
M
MDFS (Microsoft Distributed Filesystem):
see DFS.
Mirroring:
In a NAS, the automated process of simultaneously writing data to two (or more) hard
disk drives. Mirroring creates a redundant repository of data, such that if one of the hard disk drives
(HDD) fails, the redundant drive continues to provide access to the stored data for connected users.
Network administrators can then replace the failed drive with a new drive that can be re-mirrored to
the good drive. RAID level 1 uses mirroring.
MTBF (Mean Time Between Failures):
A measurement of hardware product reliability typically
indicated in thousands, tens of thousands, or hundreds of thousands of operational hours between
failures. It is most often defined as the average time between failures. MTBF can be derived from
extensive and time intensive testing of the working product, calculated from actual product field
performance (depending on the product, its market, its usage, and the ability to retrieve accurate
usage data), or from a calculated prediction based on known factors. Manufacturers provide MTBF
as a reference of the product’s, or its subcomponent’s reliability. Customers can use the MTBF to
determine their service needs to maintain or replace the product.
N
NAS (Network Attached Storage:
A data storage device on a computer network to provide a
centralized repository of data that can be shared and accessed by other end-users or workgroups
on the network. The Linksys Business Series NSS products are NAS devices.
NFS:
Network Filesystem. A protocol suite developed and licensed by Sun Microsystems that allows
different makes of computers running different operating systems to share files and disk storage.
NIS:
Network Information Service (formerly known as Yellow Pages). A system by which one
machine (the master) holds the Ethernet addresses of other machines (the servants). NIS is an
insecure alternative to DNS.
NTFS:
New Technology Filesystem. Windows NT standard filesystem and its descendants: Windows
2000, Windows XP, Windows Server 2003 and Windows Vista. NTFS replaced Microsoft’s
previous FAT filesystem, used in MS-DOS and early versions of Windows, and offers improvements
over FAT such as improved support for metadata and the use of advanced data structures to improve
performance, reliability and disk space utilization plus additional extensions such as security access
control lists and filesystem journaling.
