innovaphone gateway
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types: Source NAT, which is where the source IP address is replaced, and
Destination NAT, where the destination IP address is replaced.
NBTSTAT
Displays NetBIOS over TCP/IP protocol statistics (NetBT), NetBIOS name
tables for local and remote computers and the NetBIOS name cache. Nbtstat
allows a refresh of the NetBIOS name cache and the names registered in
WINS (
W
indows
I
nternet
N
ame
S
ervice).
NI
NI1 is the national ISDN protocol used in the United States for the D
channel. Some telecommunication companies still use the older 5ESS
protocol. Compared with the European DSS1, NI1 and 5ESS differ primarily
in the transmission speed. In both cases, merely data transfers at a speed of
56 kBit/s are possible. The remaining 8 kBit/s are used to transfer the
control data, since the two protocols do not support a separate D channel.
Furthermore, many of these accesses have only one B channel.
NMBLOOKUP
With nmblookup, NetBIOS names can be queried under Linux using NetBIOS
over TCP/IP.
NTP
The NTP protocol (
N
etwork
T
ime
P
rotocol) is a standard for synchronising
clocks in computer systems over packet-based communication networks.
NTP uses the connectionless network protocol UDP (
U
ser
D
atagram
P
rotocol). It was specially developed to allow a reliable time specification
over networks with a variable packet runtime.
O
OSI
The OSI reference model (
O
pen
S
ystems
I
nterconnection) is a layer model
for the communication of open, information processing systems. It
comprises standardised methods and rules for the exchange of data. The
OSI model has been developed since 1979 and has been standardised by
the ISO. It is used as the basis for a series of manufacturer-independent
network protocols, which are used almost exclusively in the transport
