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Summary - A typical PC running Linux can be turned into a remote accessserver bristling with 48 modems cheaply and easily with Digiserial cards. Read Rawn Shah's review to find out if thissolution is right for you.(1,800 words)
Digi has long been known in the ISP industry for its serial cards. Inthe days before densely-packed, single-box modem servers were available ataffordable prices, many smaller ISPs went for these multiport cards andhooked separate analog modems to them to provide their services. The result wasa host computer with a Medusa's head of analog modems sproutingfrom the back of the card.
Digi is still in the business of serial cards, but now makes multiport ISDNand analog modem cards for PC servers as well. Now you can fit a pack ofmodems within your PC server connected directly to your PCI cards, andsave yourself the trouble of snaking cables.
Ana-Digi
Digi sent us a four-port version of its analog modem card, theAcceleport RAS 4. We planned to look at the DataFire RAS card that cansupport both ISDN and analog modem connections; unfortunately, we couldnot test the Basic Rate Interface (BRI) or Primary Rate Interface (PRI)ISDN connections at this time. The DataFire series can operate at bothISDN rates of 128 Kbps, and V.90 or K56Flex analog modem speeds of up to56 Kbps; 4-, 24-, and 48-modem models are available. The 4-modem model takes4 BRI connections, while the others take one and two PRI connections (eachPRI is the equivalent of 24 B- channels) respectively.
The Acceleport RAS is the latest generation of Digi's analog multiportmodems; with it, you can integrate four or eight modems in each PCI slotand support up to 32 modems in the average server PC with four PCIslots. This turns your Linux system into a reasonable remote accessserver.
Digi provides a device driver for the DataFire and Acceleport RAS adaptersfor Linux that currently only runs on the i386 platform. The driver issupported on Red Hat 5.2, 6.x, Debian 2.1 and TurboLinux Server 4.0 withkernel version 2.0.36 and 2.2.5-22 to 2.2.14. It also requires the tix andswig software applications to be installed, since it includes some programswritten in Tcl. We tested the RAS 4 in an IBM Netfinity 5000 server with a350 MHz Pentium II in it and 128...