Preface - Draytek VIGOR 3300 User Manual

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P r e f a c e
P r e f a c e
The Vigor3300 Series integrates a rich suite of functions, including NAT, firewall, VPN, load
balance, bandwidth management, and VoIP capability. These products are very suitable for
providing multi-integrated solutions to SME markets. An application scenario for the
Vigor3300 Series is depicted in Figure 1-1, which illustrates interconnections among branch
offices through the Internet via the Vigor3300 Series routers. By combining with an existing
PABX, an Internet phone from a remote branch can also access any extension number on a
local PABX or a traditional phone via PSTN. Also, by combining load balancing, data security,
and Internet phone features, the company can benefit from reducing operation fees.
A Virtual Private Network (VPN) is an extension of a private network that encompasses links
across shared or public networks like an Intranet. A VPN enables you to send data between
two computers across a shared public Internet network in a manner that emulates the
properties of a point-to-point private link. The DrayTek Vigor3300 Series VPN router
supports Internet-industry standards technology to provide customers with open, interoperable
VPN solutions such as X.509, DHCP over Internet Protocol Security (IPSec) up to 200 tunnels,
and Point-to-Point Tunneling Protocol (PPTP).
Internet Telephony, also known as Voice over Internet Protocol (VoIP), is a technology that
allows you to make telephone calls using a broadband Internet connection instead of a regular
(analog) phone line. Combining a PABX with a V3300V allows you to call anyone who has
an Internet phone or a traditional telephone number – including local, long distance, mobile,
and international numbers. Internet Telephony offers features and services that are unavailable
with a traditional phone at no additional cost. Because Internet Telephony requires strictly
minimal packet delay and jitter (since voice quality is intolerant of packet loss), the
Vigor3300V integrates VoIP feature with QoS and packet loss concealment mechanisms to
effectively transport high priority voice traffic over IP with low latency. Another feature is
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Vigor3300 Series User's Guide