ZyXEL Communications SBG5500-A, Руководство пользователя

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Chapter 5 WAN/Internet
SBG5500 Series User’s Guide
50
(Internet Service Provider). If your ISP offers a dial-up Internet connection using PPPoE (PPP over
Ethernet), they should also provide a username and password (and service name) for user
authentication.
WAN IP Address
The WAN IP address is an IP address for the SBG, which makes it accessible from an outside network. It is
used by the SBG to communicate with other devices in other networks. It can be static (fixed) or
dynamically assigned by the ISP each time the SBG 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).
ATM
Asynchronous Transfer Mode (ATM) is a 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 Finding Out More
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.
3G
3G (Third Generation) is a digital, packet-switched wireless technology. Bandwidth usage is optimized as
multiple users share the same channel and bandwidth is only allocated to users when they send data. It
allows fast transfer of voice and non-voice data and provides broadband Internet access to mobile
devices.
IPv6 Introduction
IPv6 (Internet Protocol version 6), is designed to enhance IP address size and features. The increase in
IPv6 address size to 128 bits (from the 32-bit IPv4 address) allows up to 3.4 x 10
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IP addresses. The SBG
can use IPv4/IPv6 dual stack to connect to IPv4 and IPv6 networks, and supports IPv6 rapid deployment
(6RD).
IPv6 Addressing
The 128-bit IPv6 address is written as eight 16-bit hexadecimal blocks separated by colons (:). This is an
example IPv6 address
2001:0db8:1a2b:0015:0000:0000:1a2f:0000
.
IPv6 addresses can be abbreviated in two ways:
• Leading zeros in a block can be omitted. So
2001:0db8:1a2b:0015:0000:0000:1a2f:0000
can be
written as
2001:db8:1a2b:15:0:0:1a2f:0
.