Telos Zephyr, Руководство пользователя

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Section 6.....NON-ISDN NETWORKS
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MORE NETWORK OPTIONS
Primary Rate ISDN
There is also a higher- capacity service referred to as “Primary Rate ISDN.” Similar to the
T1 technology described earlier, this permits subscriber access to up to 23 channels of
64kbps each. A customer may use as much capacity as necessary and be charged
accordingly.
Primary Rate ISDN requires a special Channel Bank or Bridge to break out the individual
channels. These are usually modular, permitting each channel ( time slot) to be used
individually as desired. Each Zephyr would require 1 or 2 channels for bi- directional
mono and stereo, respectively.
Digital Data System (DDS)
A DDS is a dedicated, “nailed- up” connection between two specific locations. Also
referred to as dedicate digital service.
Use of this service requires a CSU/DSU ( Channel Service Unit/Data Service Unit ) to
interconnect the line with the Zephyr.
Other Possibilities
Any transmission channel which can convey 56 or 64kbps synchronous digital signals in
real time may be used with the Zephyr. Possibilities include T1, satellite links, spread-
spectrum RF transmission systems, and ATM.
When considering a technology such as ATM it is essential that your service has a
“Committed Information Rate” of at least 56 or 64Kbps and that it is a “Constant Bit
Rate” service
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USING THE ZEPHYR WITH NON-ISDN NETWORKS
V.35/X.21 Network Connection
If present, the V.35/X.21 interface is supplied in the rightmost slot, looking from the
rear. It permits connection to transmission paths other than ISDN. It may also be used
with external ISDN Terminal Adapters in the (rare) case where the available ISDN
service is not compatible with the Zephyr’s internal TA.
HOT TIP! When ordering lines, such as DDS or T1, which will
not be used for interstate access be sure to file an “Interstate
Access Charge Exemption Form”. This should result in
significant savings in monthly fees.