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Q05: What are the differences between ADSL & ISDN?
A05: The two services are NOT the same. ISDN provides two voice channels or a 128 Kbps data channel while ADSL is predominantly
a data pipe providing an asymmetrical bandwidth of up to 8 Mbps downstream and 1 Mbps upstream under good conditions. However, an
ADSL access network will be an overlay network and therefore will not require the expensive and time-consuming switch upgrades that
held ISDN back for so long. If ADSL service prices resemble ISDN service prices, then one would expect ADSL to be favored for Internet
and video application.
Q06: How does ADSL compare to cable modem?
A06: ADSL provides a dedicated service over a single telephone line; cable modems offer a dedicated service over a shared media.
While cable modems have a greater downstream bandwidth capabilities (up to 30 Mbps), that bandwidth is shared among all users on a
line, and will therefore vary, perhaps dramatically, as more users in a neighborhood get online at the same time. Cable modem upstream
traffic will in many cases be slower that ADSL, either because the particular cable modem is inherently slower, or because of the rate
reductions caused by contention for upstream bandwidth slots.
Q07: Can I use the ADSL modem to do faxing?
A07: No, you can't. As the ADSL modem is not interfering with the regular phone frequencies. As such, it is not seen, nor cannot see these
frequencies. As a fax machine uses the regular frequencies, an ADSL modem cannot fax on the data frequencies used for the ADSL-
connection. However, though you are using the ADSL modem, you can still use the phone or fax machine/ fax modem at the same time
while you are connecting to Internet.
Q08: What does a Micro filter do and when do I need one?
A08: A micro filter uses a low pass filter to separate the low-end frequencies of the telephone audio spectrum from the higher frequencies
of the xDSL signals. The micro filter should be a passive device, not requiring power so that 'life-line' voice service can be provided as has
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