YML854 Rev1
NB6, NB6W, NB6Plus4W
NB6, NB6W, NB6Plus4W
User Guide
www.netcomm.com.au
15
Private IP Address
Private IP addresses are also LAN IP addresses, but are considered “illegal” IP addresses to the Internet. They
are private to an enterprise while still permitting full network layer connectivity between all hosts inside an
enterprise as well as all public hosts of different enterprises.
The ADSL Router uses private IP addresses by assigning them to the LAN that cannot be directly accessed
by the Internet or remote server. To access the Internet, private network should have an agent to translate the
private IP address to public IP address.
Public IP Address
Public IP addresses are LAN IP addresses that can be considered “legal” for the Internet, because they can
be recognized and accessed by any device on the other side of the DSL connection. In most cases they are
allocated by your ISP.
If you are given a range of fixed IP addresses, then one can be assigned to the router and the others to
network devices on the LAN, such as computer workstations, ftp servers, and web servers.
PvC (Permanent virtual Circuit)
A PVC is a logical point-to-point circuit between customer sites. PVCs are low-delay circuits because routing
decisions do not need to be made along the way. Permanent means that the circuit is preprogrammed by the
carrier as a path through the network. It does not need to be set up or turned down for each session.
RIP (Routing Information Protocol)
RIP is a routing protocol that uses the distance-vector routing algorithms to calculate least-hops routes to
a destination. It is used on the Internet and is common in the NetWare environment. It exchanges routing
information with other routers. It includes V1, V2 and V1&V2, which controls the sending and receiving of RIP
packets over Ethernet.
UDP (User Datagram Protocol)
UDP is a connectionless transport service that dispenses with the reliability services provided by TCP. UDP
gives applications a direct interface with IP and the ability to address a particular application process running
on a host via a port number without setting up a connection session.
virtual Server
You can designate virtual servers, e.g., a FTP, web, telnet or mail server, on your local network and make them
accessible to the outside world. A virtual server means that it is not a dedicated server -- that is, the entire
computer is not dedicated to running on the public network but in the private network.
vPI (virtual Path Identifier) & vCI (virtual Channel Identifier)
A VPI is a 8-bit field while VCI is a 16-bit field in the ATM cell header. A VPI identifies a link formed by a
virtual path and a VCI identifies a channel within a virtual path. In this way, the cells belonging to the same
connection can be distinguished. A unique and separate VPI/VCI identifier is assigned in advance to indicate
which type of cell is following, unassigned cells, physical layer OAM cells, metasignaling channel or a generic
broadcast signaling channel. Your ISP should supply you with the values.
