ZyXEL Communications P-873HNU-51B, User Manual

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Chapter 6 Broadband
P-873HNU(P)-51B User’s Guide
66
WAN IP Address
The WAN IP address is an IP address for the VDSL Router, which makes it accessible from an
outside network. It is used by the VDSL Router to communicate with other devices in other
networks. It can be static (fixed) or dynamically assigned by the ISP each time the VDSL Router
tries to access the Internet.
If your ISP assigns you a static WAN IP address, they should also assign you the subnet mask and
DNS server IP address(es) (and a gateway IP address if you use the Ethernet encapsulation
method).
ATM
Asynchronous Transfer Mode (ATM) is a LAN and WAN networking technology that provides high-
speed data transfer. ATM uses fixed-size packets of information called cells. With ATM, a high QoS
(Quality of Service) can be guaranteed. ATM uses a connection-oriented model and establishes a
virtual circuit (VC) between two endpoints before the actual data exchange begins.
PTM
Packet Transfer Mode (PTM) is packet-oriented and supported by the VDSL2 standard. In PTM,
packets are encapsulated directly in the High-level Data Link Control (HDLC) frames. It is designed
to provide a low-overhead, transparent way of transporting packets over DSL links, as an
alternative to ATM.
Multicast
Traditionally, IP packets are transmitted in one of either two ways - Unicast (1 sender - 1 recipient)
or Broadcast (1 sender - everybody on the network). Multicast delivers IP packets to a group of
hosts on the network - not everybody and not just one.
IGMP
IGMP (Internet Group Multicast Protocol) is a network-layer protocol used to establish membership
in a Multicast group - it is not used to carry user data. There are three versions of IGMP. IGMP
version 2 and 3 are improvements over version 1, but IGMP version 1 is still in wide use.
Finding Out More
See Section 6.4 on page 76 for technical background information on WAN.
6.1.2 Before You Begin
You need to know your Internet access settings such as encapsulation and WAN IP address. Get this
information from your ISP.