ZyXEL Communications 2602HWNLI-D7A User Manual
Prestige 2602HWNLI-D7A Support Notes
All contents copyright (c) 2007 ZyXEL Communications Corporation.
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Can I make an outgoing PSTN call through P2602HWNLI
– D7A?
Yes, P2602HWNLI – D7A allows you to make outgoing PSTN call via a prefix number that is defined in the
configurable lifeline table. It allows you to store up to 9 pre-stored numbers. If P2602HWNLI- D7A lost
power it will by pass to PSTN line to allow you to call out as you where on regular PSTN phone.
power it will by pass to PSTN line to allow you to call out as you where on regular PSTN phone.
VoIP FAQ
What is Voice over IP?
Voice over IP is an emerging technology based on open standards of IEEE, fundamentally the Internet Protocol,
that allows voice data to travel across the Internet. There are many method to used this technology, the most
common and well known are SIP, and H.323.
that allows voice data to travel across the Internet. There are many method to used this technology, the most
common and well known are SIP, and H.323.
How does Voice over IP work?
Basically VoIP is a technic to send voice information in digital form in discrete packets over digital network
rather than by using traditional circuit switch (PSTN). To do so we will need an analog to digital converter on
sender side to translate the voice (analog signal) to digital than transmit it, and on the receiver end it will also
need an analog to digital converter to covert the digital signal back to analog to the person being called can
heard the voice.
heard the voice.
Why use VoIP?
Traditionally telephony carrier use circuit switching for carrying voice traffic. As circuit switching is designed
to carry voice and it does it very well. Than why use IP for voice? As broadband booms, and technology
evolve. People now want to communicate through various way not just voice such as email, instant
messaging, video and so on. Traditional telephony can not evolve as quickly as the demand and develop new
messaging, video and so on. Traditional telephony can not evolve as quickly as the demand and develop new
feature on circuit switch takes much time and money. IP is an already exist standard and many type of service
already runs on IP, by using IP as a platform integrate service is now possible and low cost where traditional
circuit may take long time to achieve.
already runs on IP, by using IP as a platform integrate service is now possible and low cost where traditional
circuit may take long time to achieve.
What is the relationship between codec and VoIP?
In order to transfer voice (analog signal) over IP it first need to be digitized. Codec is a technic to digitize
analog signal to digital and vice versa. There are various speech codec available and can be used with VoIP
each with it's advantage and disadvantage.
each with it's advantage and disadvantage.