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Product Overview
Product Overview
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Recent Developments
Even as streaming audio and video over the Internet became common, VoIP
quality was still sub-par. What, you may ask, is the reason for this? While
it’s relatively easy to convert a song or even a video into IP-based packets
and have it arrive in decent shape, the Internet was not designed as a two-
way street, i.e., to support two-way communications as in your typical
conversation. Early VoIP calls were much like walkie-talkie speech, halting and
unsynchronized. A common trick was to let the other speaker know you had
finished talking by ending your statement with the word “Over.” For example,
“How are you today? Over.” “Not too good, I think I’ve the flu. Are you busy?
Over.”
This method was effective, but hardly conducive to a comfortable conversation!
Therefore, substantial cost savings, although attractive, were not enough to
make up for unacceptably poor call quality. Now, however, thanks to dedicated
hardware processing and protocols like Session Initiation Protocol (SIP), VoIP
can be as smooth as a session that uses the regular telephone network, greatly
increasing its appeal.
Equally as important to VoIP’s recent surge has been the widespread adoption
of broadband in both homes and businesses, which delivers the bandwidth
required to come close to PSTN quality.
Features and Benefits
NAT also enables multi-user Internet access via a single user account, and
virtual server functionality (providing protected access to Internet services such
as Web, FTP, email, and Telnet) VPN pass-through (IPSec-ESP Tunnel mode,
L2TP, PPTP) User-definable application sensing tunnel supports applications
requiring multiple connections easy setup through a web browser on any
operating system that supports TCP/IP compatible with all popular Internet
applications.
VoIP Features and Benefits
Full Session Initiation Protocol (SIP) support
Voice Activity Detection (VAD) conserves bandwidth
Quality of Service (QoS) provides superior voice quality
Voice over IP (VoIP)
An Introduction
Using Voice over IP (VoIP), instead of making calls over the regular telephone
network, calls are made over computer (IP) networks, either through your
Internet Service Provider’s connection or through your local network. Calls
made are generally cheaper than traditional calls.
The basic steps involved in VoIP include the conversion of an analog voice
signal to digital, the encoding and then compression of the signal into Internet
Protocol (IP) packets. The VoIP Router is equipped with a digital signal
processor (DSP), which segments the voice signal into frames and stores them
in voice packets. Using the industry standard codecs, G.711, G.723.3 and
G.729, these packets are encoded. These IP packets are then transmitted in
accordance with International Telecommunications Union specification SIP over
the Internet to their destination where the process is reversed.
Advantages of Using VoIP
The main advantage of VoIP over the traditional Public Switched Telephone
Network (PSTN) is the ability to make low-cost calls over the IP network. One
of the greatest benefits is cheaper long distance calls.
Past Problems
Internet-based telephony has been around for years but, until now, has not
reached the mainstream market.
Products with a true cost-saving advantage over standard telephones do not
have comparable call quality. Users experience a prolonged delay making
conversation difficult.
Call-completion rates are very low due to firewalls and the use of Network
Address Translation (NAT), which renders over 50% of residential computers
unable to communicate with traditional VoIP software.
The user interface is complicated, and requires substantial configuration and
technical skills.
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