ADSL Router User Manual
The ADSL Router uses private IP addresses by assi gning them to the LAN that cannot be directly
accessed by the Internet or r t, private network should have an
agent to translate the private

Public IP Address

Public IP addresses are LA N IP addresses that can be consi dered “legal” for the Internet,
because they can be recognized and acce ssed by any device on the other side of the DSL
r ISP.
e
int-to-point circuit between customer sites. PVCs are low-delay circuits
up or turned down for each sessi on.
n process ru nning on a host via a port number without setting up a connection session.
l servers, e.g., a FTP, web, telnet or mail server, on yo ur local network
in the

fier)

entifier
emote server. To access the Interne
IP address to public IP address.
connection. In most cases they are allocated by you
If you are given a range of fixed IP addresses, then one can be assigned to the router and th
others to network device s on the LAN, such as computer workstations, ftp servers, and web
servers.

PVC (Permanent Virtual Circuit)

A PVC is a logical po
because routing decisi ons 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

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 parti cular
applicatio

Virtual Server

You can designate virtua
and make them accessi ble to the outside world. A virtual server means that it is not a dedicated
server -- that is, the entire computer i s not dedicated to running on the public network but
private network.

VPI (Virtual Path Identifier) & VCI (Virtual Channel Identi

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 id
is assigned in advance to indicate which type of cell is following, unassigned cells, physical layer
OAM cells, metasignaling channel or a g eneric broadcast signaling channel. You r ISP should
supply you with the values.
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