Installation guide

iSR6200 Intelligent Storage Router
Installation Guide
Glossary-6 ISR651101-00 C
NIC
Network interface card. Computer card
installed to enable a dedicated network
connection.
NL_Port
Node loop port. A port capable of
arbitrated loop functions and protocols. An
NL_Port connects through an arbitrated
loop to other NL_Port and at most a single
FL_Port. NL_Ports handle creation, detec-
tion, and flow of message units to and
from the connected systems. NL_Ports are
end ports in virtual point-to-point links
through a fabric, for example NL_Port to
F_Port to F_Port to N_Port using a single
Fibre Channel fabric switch. In the
absence of a fabric switch FL_Port,
NL_Ports can communicate with other
NL_Ports in virtual point-to-point links
through an FC_AL open loop circuit often
through FC_AL (Arbitrated Loop) hub or
loop switch devices. See: E_Port, F_Port,
FL_Port, G_Port, N_Port.
NTP
Network time protocol. NTP is used for
distributing the Coordinated Universal
Time (UTC) by means of synchronizing the
clocks of computer systems over
packet-switched, variable-latency data
networks.
NVRAM
Non-volatile random access memory.
NVRAM is a type of memory that retains
data (including configuration settings)
even when power is removed. You can
configure NVRAM settings manually or
restore them from a file.
OC
Optical carrier is a standardized set of
specifications of transmission speeds that
describe a range of digital signals that can
be carried on synchronous optical
networking (SONET) fiber optic networks.
The number attached to the optical carrier
abbreviation, OC-12, is directly propor-
tional to the data rate of the bitstream of
the digital signal.
path
A path to a device is a combination of a
adapter port instance and a target port as
distinct from internal paths in the fabric
network. A fabric network appears to the
operating system as an opaque network
between the adapter (initiator) and the
target.
Because a path is a combination of an
adapter and a target port, it is distinct from
another path if it is accessed through a
different adapter and/or it is accessing a
different target port. Consequently, when
switching from one path to another, the
driver might be selecting a different
adapter (initiator), a different target port, or
both.
This is important to the driver when
selecting the proper method of failover
notification. It can make a difference to the
target device, which might have to take
different actions when receiving retries of
the request from another initiator or on a
different port.
PCM
Power and cooling module. A device that
consists of one power supply and three
fans.