Comparison of Options | signotec Knowledge Base

This page compares the available mechanisms for using signotec signature pads on a terminal server and provides guidance for choosing the right variant.

Comparison Table

Criterion	Virtual Channel	Virtual Serial Connection	Native USB Redirection	Network Connection
Citrix Virtual Apps and Desktops	✅	✅	✅ (Generic USB Redirection)	✅
Microsoft RDP	–	✅	✅ (USB redirection / "RemoteFX")	✅
Other Remote Protocols	–	✅ if COM mapping is supported	✅ if USB redirection is supported	✅
Device Requirement	any	FTDI pads (`FT100`) or USB pads (`U100`) with VCOM driver	any	USB pads (`U100`) with USB-Ethernet adapter or signotec Delta with integrated RJ45
Client Driver Required	signotec Virtual Channel driver	`FT100`: standardized FTDI driver¹. `U100`: signotec VCOM driver	–	–
signotec License Required	yes, Virtual Channel driver	only with the VCOM variant	–	–
Performance / Latency	very good	good	low	very good
Suitability for Pads with Color Display	very good	good	low	very good
Client-Independent	–	–	–	✅
Pad Shareable (Multiple Workstations)	–	–	–	✅
Configuration Effort	Driver rollout + Citrix policy	COM mapping in the session (+ driver rollout for VCOM)	Citrix policy or RDP GPO	Pad and application configuration, network configuration if applicable

¹ The FTDI driver is usually part of the Linux kernel. On Windows, it is usually installed automatically via Windows Update as soon as the pad is connected.

Decision Guide

Citrix Environment

If deploying the signotec Virtual Channel driver to the clients is possible (software deployment via SCCM/Intune/IGEL UMS or similar), the Citrix Virtual Channel is the recommended option. Lowest latency, best stability, dedicated channel over the ICA protocol.

Where driver rollout is not possible or the Virtual Channel is not an option for other reasons, the Network Connection is in most cases the next-best choice. This requires suitable devices (USB variant with adapter, or Delta with RJ45) and appropriate network infrastructure.

Alternatively, USB Redirection and the Virtual Serial Connection remain available as options.

Pure RDP Environment

For pure RDP environments, the Virtual Channel is currently not available.

Recommendations:

Network Connection, provided the hardware and network infrastructure are suitable.
Virtual Serial Connection with FT100 devices (no additional driver required) or U100 devices with the signotec VCOM driver.
USB Redirection as a fallback. Based on our experience, RDP USB redirection (historically "RemoteFX USB Redirection") is usually not suitable for production use in terms of latency and stability.

Other Remote Protocols

For VMware Horizon, Parallels RAS, and other solutions, the Network Connection is the most robust option, since it works independently of the remote protocol. The Virtual Serial Connection and USB Redirection can generally also be used, provided the respective remote protocol supports COM or USB mapping. Suitability in the specific environment must be verified by the administrator.

Pad Is to Be Used from Multiple Workstations

Only the Network Connection supports this use case. The pad is not tied to a specific client and can be addressed sequentially from different workstations.

Restricted Endpoints (No Driver/Software Deployment Possible)

Options include the Virtual Serial Connection with FT100 devices (the FTDI driver is present on Linux clients as a kernel module and is usually downloaded automatically on Windows via Windows Update), USB Redirection, and the Network Connection. Given suitable hardware, the Network Connection is the most robust option; otherwise, the FT100 variant is usually more straightforward than native USB Redirection.

Hardware Requirements Overview

The individual options require different pad variants. The item number of the signotec signature pads indicates the connection type:

FT100 — integrated USB-to-serial converter (FTDI chip). Appears on the client as a COM port. Suitable for the Virtual Serial Connection without an additional signotec driver.
U100 — USB connection (HID or WinUSB). Suitable for Citrix Virtual Channel, USB Redirection, Virtual Serial Connection with the signotec VCOM driver, and Network Connection via the USB-Ethernet adapter.
signotec Delta with RJ45 — optional configuration with an integrated network port. Suitable for the Network Connection without an additional adapter. Cannot be retrofitted.

Detailed information on connection type, power supply, and variant availability can be found in the respective signature pad manual.