Netopia 6.3 - Manual (Page 153)

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Appendix B
-----M-----
magic number Random number generated by a router and included in packets it
sends to other routers. If the router receives a packet with the same
magic number it is using, the router sends and receives packets with
new random numbers to determine if it is talking to itself.
MD5 A 128-bit, message-digest, authentication algorithm used to create
digital signatures. It computes a secure, irreversible, cryptographically
strong hash value for a document. Less secure than variant SHA-1.
metric Distance, measured in the number of routers a packet must traverse,
that a packet must travel to go from a router to a remote network. A
route with a low metric is considered more efficient, and therefore
preferable, to a route with a high metric. See hop count.
modem Modulator/demodulator. Device used to convert a digital signal to an
analog signal for transmission over standard telephone lines. A
modem at the other end of the connection converts the analog signal
back to a digital signal.
MRU Maximum Receive Unit. The maximum packet size, in bytes, that a
network interface will accept.
MTU Maximum Transmission Unit. The maximum packet size, in bytes, that
can be sent over a network interface.
MULTI-LAYER The Open System Interconnection (OSI) model divides network traffic
into seven distinct levels, from the Physical (hardware) layer to the
Application (software) layer. Those in between are the Presentation,
Session, Transport, Network, and Data Link layers. Simple first and
second generation firewall technologies
inspect between 1 and 3 lay-
ers of the 7 layer model, while our SMLI engine inspects layers 2
through 7.
-----N-----
NAK Negative acknowledgment. See ACK.
Name The Name parameter refers to the name of the configured tunnel. This
is mainly used as an identifier for the administrator. The Name param-
eter is an ASCII and is limited to 31characters. The tunnel name is the
only IPSec parameter that does not need to match the peer gateway.
NCP Network Control Protocol.
Negotiation Method This parameter refers to the method used during the Phase I key
exchange, or IKE process. SafeHarbour supports Main or Aggressive
Mode. Main mode requires 3 two-way message exchanges while
Aggressive mode only requires 3 total message exchanges.
null modem Cable or connection device used to connect two computing devices
directly rather than over a network.
-----P-----
packet Logical grouping of information that includes a header and data.
Compare frame, datagram.
PAP Password Authentication Protocol. Security protocol within the PPP
protocol suite that prevents unauthorized access to network services.
See RFC 1334 for PAP specifications. Compare CHAP.
parity Method of checking the integrity of each character received over a
communication channel.
Peer External IP Address The Peer External IP Address is the public, or routable IP address of the
remote gateway or VPN server you are establishing the tunnel with.