I
NTRODUCTION
1-3
•
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.
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 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.
Содержание ARV3515J-A-GP
Страница 1: ...ARV3515J A GP March 2005 150000007300J VoIP ADSL Router SIP DRAFT ...
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Страница 42: ...CONFIGURING YOUR MACINTOSH COMPUTER 3 18 ...
Страница 97: ...ADSL 4 55 Status The Status page displays ADSL status information ...
Страница 128: ...TROUBLESHOOTING A 4 ...
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Страница 142: ...Model Number ARV3515J A GP 150000007300J E032005 R01 F1 0 ...