StarTech.com SV841DUSBI - Manual (Page 38)

Instruction Manual
33
Using the Modem feature
Background
The modem feature allows the IP KVM to act as an Internet connection server for
increased security and flexibility in connecting with the host computer. Unlike the TCP/
IP connection used with the standard Web configuration and VNC clients, the modem
creates a one-to-one connection between the IP KVM and the computer you are using
to manage the host computer that is essentially private, as it bypasses the public
Internet completely.
Note: this feature requires both an external modem (most standard connection
protocols are supported) and a dedicated phone line that can be connected to the
modem for external access. While it is possible to use the modem feature through
some PBX systems, this increases the complexity and reduces the performance of
the connection. For clarity, the instructions presented here assume that the modem
is connected to a typical POTS (plain old telephone system) line that is not routed
through a phone management system or shared with other devices. If you wish to use
this feature through a PBX system, it may require some experimentation and additional
support from your telecom services provider, and is not supported by StarTech.com.
Connecting a Modem
The IP KVM will work with virtually any Hayes-compatible modem that recognizes
the standard AT command set. Some modem manufacturers offer “enterprise” grade
modem products (at a premium price) 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 IP KVM.
It is important to note that modems that offer “56K” (or 57,000 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 57,000 bps do not indicate a problem