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FarSync DSL-S1 card - G.SHDSL PCI adapter for Linux and Windows


The FarSync DSL-S1 universal PCI / PCI-X card provides a versatile high performance G.SHDSL (also known as SHDSL and SDSL) connectivity to the Internet, local private connections or to corporate networks

G.SHDSL PCI card - FarSync DSL-S1
The product datasheet in Acrobat PDF format may be downloaded here, (size 80 Kbytes).
FarSync DSl-S1 G.SHDSL Product DatasheetGet Reader


The intelligent FarSync DSL-S1 card brings comprehensive SHDSL support to Linux and Windows. Full duplex 2 wire bandwidth of 2.304 Mbits/s is supported down to fractional speeds of 192 Kbits/s with automatic configuration.

Whether you are connecting to the Internet, private networks using TCP/IP or interconnecting sites for back to back operation using leased lines, a FarSync adapter provides the connectivity solution replacing standalone routers and firewalls with an integrated solution on a PC/Server.

Linux: The card installs seamlessly under Linux kernel series 2.4 and 2.6 on single, multiprocessor, 32 and 64 bit systems. Distributions by Redhat, SuSE, Slackware, Mandriva, Debian, Ubuntu, Fedora and many more are supported.

Windows: The card can be installed on Windows XP, Windows Server 2003, Windows 2000 and Vista 32 bit.

Under TCP/IP the link level protocol can be MPoA (Cisco HDLC, Frame Relay or Ethernet 802.2 over ATM) or PPPoA (PPP over ATM AAL5). The SHDSL port provides a standard point-to-point network interface controllable with all the standard networking tools.

FarSync DSL-S1 cards can be used in a bonded configuration where 2 or more G.SHDSL lines can be 'bonded' together using PPP-MP. Line bonding has become an increasingly popular way of obtaining a higher bandwidth connections.

The compact design allows the card to be compatible will both standard and low profile systems, standard and low profile PCI connector plates are supplied.

Typical Applications

The FarSync DSL-S1 is suitable for connection to TCP/IP and Frame Relay networks. Typical applications include:

  • Integration with embedded Linux or Windows based Products
  • G.SHDSL Internet Access
  • Remote office access back to back operation over leased lines including wire only links
  • Server-based network hub (Routers & Firewalls)
  • Video Teleconferencing
  • VOIP systems


Most commonly known as SHDSL, G.991.2 and also under the generic name SDSL, G.SHDSL is an international standard for symmetric DSL developed by the ITU. G.SHDSL provides for sending and receiving high-speed symmetrical data streams over a single pair of copper wires (2 wire) at rates between 192 Kbits/s and 2.304 Mbits/s. G.SHDSL was developed to replace several incompatible symmetric DSL technologies (e.g. SDSL, HDSL, HDSL2) with a globally supported standardised technology incorporating performance and interoperability enhancements.

High Performance and Flexibility

The FarSync DSL-S1 is designed for high performance and flexibility. The intelligent card is driven by an AMD processor has zero wait state SRAM and a PCI Bus mastering DMA interface to provide very high performance whilst minimising PCI and Server CPU loads.

Multiple FarSync DSL-S1 cards can be installed and also intermixed with the other adapters in the FarSync WAN T-Series range that provide E1, X.21, V.35 and RS-530 network interfaces.

The FarSync DSL-S1 cards can be used in a bonded configuration where 2 or more G.SHDSL lines can be 'bonded' together to support a faster connection. Bonding is achieved by using multilink PPP (PPP-MP - RFC 1990) to aggregate the datastreams on 2 or more lines and provide a streamlined higher bandwidth pipe to the IP layer. This method is very useful for providing a doubling up of data transfer rates where the SDSL connection speed is limited by the length of the wire connection or where simply, higher bandwidth is required.

PCI Bus Compatibility

The FarSync DSL-S1 is PCI version 2.2 compliant and PCI-X compatible. This Universal PCI card can operate in PCs using either 3.3 volt or 5 volt signaling. The card is suitable for PCs with either 32 bit bus or 64 bit bus configurations. The power for the cards is taken from the 3.3 volt supply rail.


Installation and Configuration

A simple installation procedure will make the device driver available via the standard kernel configuration mechanism. The driver may be either permanently linked to the kernel or used as a dynamically loadable module.

A configuration tool is provided to set the interface parameters and the protocol, after which the ports may be configured with standard networking tools. The line speed is automatically detected and configured and there is also provision for a manual override. Examples and default configurations are provided with the on-line documentation.

Port Monitoring

A daemon is included that allows the Activation Status of the port to be automatically monitored.  The network interface associated with the specific SHDSL port can then be brought up or down to reflect the line state.  This allows routing tables to be dynamically recalculated to reflect destinations actually available.


Product Packaging

The product includes the communications card, RJ11 2 metre cable, standard and low profile PCI connector plates, Windows driver software, Linux driver software (with source), utilities, test program and documentation supplied on CD-ROM.

Hardware Technical Specifications

Product Name

FarSync DSL-S1

PCI-X G.SHDSL card the FarSync DSL-S1

Product Code



5 years

Port Count

1 port

Hardware Features

Card type /
PCI specification

Intelligent Universal bus mastering PCI card,
AMD processor, zero wait state SRAM,
Short card (height 65mm, length 167mm),
PCI-X compatible,
PCI v2.2 compliant,

Supports 3.3 & 5 volt signaling,
Suitable for 32 and 64 bit PCI bus slots

Network modes and compatibility

RT (remote terminal - Client),
COT (central office terminal - Server),
Analogue Loopback for testing, transparent and non-transparent,
ITU G991.2 Annex A (US operation), Annex B (Europe), G.994.1

Network connection cable

JCD1 2 metre RJ11 connector cable included

Link speed range

2 wire operation - 192 Kbits/s to 2.304 Mbits/s

ESD protection

Line protection meets TBR12/13

Back panel indicators

Line status reported by 4 LEDs


EN55022 class B, CE, FCC class B, TBR12 and TBR13

Power requirements

< 1.5 Amp @ +3.3v, < 5 watts

RoHS Compliance

See the RoHS news item

Software Technical Specifications

Software Features

Standard interfaces

Configurable and controllable with all standard networking tools.

Multiple cards

Yes, up to 12 or more in a Server, only limited by PCI slots, can be intermixed with FarSync WAN T-Series cards


PPPoA - PPP over AAL5 ATM (RFC 2364),
MPoA - Multiple Protocols over ATM (Frame Relay, Cisco HDLC, Ethernet 802.2 - RFC 2684 formerly 1483),
ATM PVC support configurable with VPI/VCI,
PPP (RFC 1661), including multilink PPP, also known as PPP-MP, MLP or MLPPP (RFC 1990),
SNMP (RFC 1213)




Port Monitoring Daemon - Monitors Activation Status and configures the network interfaces


Full installation and configuration instructions provided on-line

Linux support

Distributions by Redhat, SuSE, Slackware, Mandriva, Ubuntu, Debian, Fedora and more.
Drivers for kernel series 2.4 and 2.6 on both single and multiprocessor 32 and 64 bit systems

Windows support

Windows XP, Windows Server 2003, Windows 2000 and Vista 32 bit

Information in this document is subject to change without notice.
Other products and companies referred to herein are trademarks or registered trademarks of their respective companies or mark holders.


Last updated: 08-Nov-2007