Wireless Modem Router User's Manual

ADSL Router User Manual
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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.