StarTech.com SV3253DXI - Manual (Page 54)

Instruction Manual
49
Connecting a Modem
The SVxx53DXI will work with virtually any Hayes-compatible modem that recognizes
the standard AT command set. Some modem manufacturers offer “enterprise” grade
modem products that include technology to improve the stability of connections;
whether this type of product would be beneficial to your application depends on
whether you consider the modem connection to be mission-critical, the quality of your
telecom infrastructure, and your budget for implementing this solution. The model of
modem attached is essentially transparent to the SVxx53DXI.
It is important to note that modems that offer “56K” (or 56,000 bps) connections often
achieve connection speeds that are far lower than their maximum capabilities. Given the
limitations of telecom infrastructure (many locations have yet to implement fully digital
switching technology, and still rely on older analog technology for some segments), the
maximum “upstream” transfer rate is limited to a maximum of 33,600 bps between two
modems; the “downstream” rate is often within a similar range for a typical connection.
Therefore, speeds below 56,000 bps do not indicate a problem with the modem or the
SVxx53DXI, but simply reflect the line conditions at the time the connection is made.
The serial port can be used for serial port configuration when the modem is connected.
It requires the use of a null modem serial cable.