DECserver
| Company type | Product line |
|---|---|
| Industry | Computer networking hardware |
| Founded | 1985 |
| Founder | Digital Equipment Corporation (DEC) |
| Fate | Network Products Business sold to Cabletron in 1998; later became part of Digital Networks / Vnetek Communications |
Area served | Worldwide |
| Products | Asynchronous console servers, terminal servers, print servers, UNIX-based application and file servers |
| Owner | Digital Equipment Corporation (initially) |
| Parent | Digital Equipment Corporation |
DECserver refers to a now-obsolete series of asynchronous console server, terminal server, and print server devices initially launched by Digital Equipment Corporation (DEC). The DECserver name was subsequently extended to UNIX-based application and file servers utilizing the MIPS CPU. This product line achieved considerable success for DEC; in February 1998, prior to DEC’s acquisition by Compaq, its Network Products Business was sold to Cabletron, which later emerged as Digital Networks (eventually Vnetek Communications) in September 2000.
Model history
The DECserver lineup was introduced in 1985, beginning with the DECserver 100. All units operated using the Local Area Transport (LAT) protocol, compatible with DEC operating systems such as VMS, RSX-11, RSTS/E, and Ultrix. These devices booted their operating systems over the network via the DECnet MOP (Maintenance Operations Protocol), with subsequent models adding support for TCP/IP booting through bootp and booting from flash memory cards.
DECserver 100 This model functioned as a network terminal switch designed for Ethernet LANs, enabling connection of up to eight DIGITAL asynchronous terminals to LAT-enabled hosts. Model: DSRVA-** Ports: 8 DB25 Alternate: DECserver 708, 8 ports DB9, DSRVW-R*
DECserver 200 Built for Ethernet LAN environments, this unit connected eight asynchronous terminals or non-LAT hosts, including PCs and dial-out modems. It offered two hardware variants: /MC featuring RS-232-C lines (DSRVB-AB) and /DL with data leads only (DSRVB-BB). Model: DSRVB-** Ports: 8 DB25 (/MC) or 8 MMJ (/DL) Alternate: DECserver 708, 8 ports DB9, DSRVW-R*
DECserver 250 A network printer server equipped with two parallel printer ports plus four serial interfaces supporting printers or terminals; communication was handled via LAT. Its software was loaded remotely from a Phase IV DECnet host. Model: DSRVP-** Ports: 7 total Alternate: None
DECserver 300 An Ethernet Communications Server capable of connecting up to sixteen asynchronous terminals using MMJ connectors and EIA 423-A electrical standards for extended cable lengths and enhanced speeds. Supported both LAT and TCP/IP protocols. Model: DSRVF-** Ports: 16 DB25 or MMJ Alternate: DECserver 708 (8 ports DB9), DECserver 716 (16 ports RJ45)
DECserver 500/550 These models could be configured with option cards to support up to 128 EIA-423-A or 64 RS-232 asynchronous ports, allowing mixed RS-232 and EIA-423-A interfaces. They supported ULTRIX host connections to printers via the LAT protocol. Configuration data was loaded from a MOP host rather than stored locally in nonvolatile memory. The design was based on the PDP-11/53 chipset, featuring up to 1.5 MB of RAM; it could be reverted to a full PDP-11/53 system by swapping PROMs. Model: DSRVS-** Ports: up to 128 Alternate: CXY08 = DECserver 708; CXA16 = DECserver 716, 732
DECserver 90L Also known as Plain Old Terminal Server (POTS), this model ran ROM-based firmware that supported only LAT without additional advanced features. Model: DSRVD-** Ports: 8 MMJ; 1 BNC Alternate: DECserver 90M+
DECserver 90L+ An eight-line terminal server offering LAT support with capability for up to four LAT sessions and one MOP session per port; intended for ThinWire Ethernet LANs. Model: DSRVG-** Ports: 8 MMJ; 1 BNC Alternate: DECserver 90M+
DECserver 90TL Supported asynchronous connections at speeds reaching up to 57.6 kbit/s across UNIX, ULTRIX, VMS, DOS, and multi-vendor networks; featured TCP/IP protocol compatibility and remote management capabilities. Model: DSRVE-** Ports: 8 RJ45; 1 BNC Alternate: DECserver 90M+
DECserver 90M Available in three versions distinguished by Flash RAM size (none, 1 MB, or 2 MB). Supported multiple protocols including LAT, Telnet, SLIP, TN3270, CSLIP, PPP; provided remote node control along with accounting event logging and audit trail functions. Model: DSRVH-** Ports: 8 RJ45; 1 BNC; 1 RJ45 LAN Alternate: DECserver 90M+
DECserver 900MC An asynchronous network access server integrating eight onboard V.34 modems. Model: DSRVX-** Ports: 8 RJ45 Alternate: None
DECserver 900GM/GMX The DECserver 900GM supported up to sixteen ports with full modem control or thirty-two ports with partial modem control; the GMX variant provided half those port counts. These units connected asynchronous devices such as terminals, printers, modems, or PCs to Ethernet LANs via four (GM) or two (GMX) high-density (68-pin) D-connectors. Each port accommodated data rates from as low as75 bit/s up to115.2 kbit/s. Included standard memory of4 MB expandable to8 MB. Model: DSRVY-** Ports:2–4 (68-pin Champ connectors) Alternate: DECserver708 (8 ports DB9), DECserver716 (16 ports RJ45)
DECserver900TM A network access server featuring32 RJ45 ports for connecting asynchronous devices with limited modem control functionality; data rates ranged from75 bit/s to115.2 kbit/s. Memory was expandable from a default4 MB up to8 MB. Model: DSRVZ-** Ports:32 RJ45 Alternate: DECserver732
DECserver700-08 Initial models (-A*, -B*) were superseded in1993 by –E* and –F* versions that offered increased memory capacity (4 MB operational plus slot for a2 MB Flash card) running the DNAS (DECserver Network Access Software). This series was discontinued in2002. Models: DSRVW-A*, B*, E*, F* Ports:8 DB25 Replaced by: DECserver708 (8 ports DB9), DECserver716 (16 ports RJ45)
DECserver700-16 Original units were replaced in1993 by –G* and –H* models featuring4 MB operational memory plus slot for a2 MB Flash card running DNAS software; these were retired in2001. Models: DSRVW-C*, D*, G*, H* Ports:16 RJ45 Replaced by: DECserver716; DECserver732
DECservers in the Present Day
DECserver 90M+
Released in 2003, the DECserver 90M+ is a comprehensive asynchronous device and remote access server offering eight asynchronous RJ45 ports that can be accessed locally or remotely over Ethernet LANs. It comes equipped with 4 MB of internal flash memory and 8 MB of RAM, supports ROM code upgrades, and allows up to eight simultaneous sessions per port. Operating on DECserver Network Access Software (DNAS), it delivers data transfer speeds reaching 230.4 kbit/s. Unlike the 90M variants, this model does not include a BNC connector.
Model number: DCSRV-** Ports: 8 RJ45
DECserver 708
Introduced in 2003 as the successor to the DECserver 700-08, this Ethernet-based terminal server facilitates connections for printers, terminals, PCs, and modems to LAN environments. It natively supports 10BaseT Ethernet and can accommodate ThinWire Ethernet/IEEE 802.3 through an adapter. The unit comes with factory-installed memory and offers optional Flash RAM expansions up to 4 MB, enabling software image downloads from either the network or local flash storage for expedited booting.
Model number: DSRVW-R* Ports: 8 DB9
DECserver 716
Debuting in 2000 as an upgrade to the DECserver 700-16, the DECserver 716 supports data rates up to 115 kbit/s per port and includes a front panel slot designed for flash memory cards. Its security suite encompasses RADIUS, Kerberos, RSA SecurID, PAP, CHAP, and CBCP dial-back authentication. The device allows multiple Telnet sessions per port and supports various protocols such as IP, LAT, Appletalk, TN3270, Rlogin, LPD, DNS, SLIP, CSLIP, and PPP with AUTOLINK functionality.
Model number: DSRVW-J* Ports: 16 RJ45
DECserver 732
Providing the same capabilities as the DECserver 716 but scaled up for larger deployments, the DECserver 732 expands port capacity to 32.
Model number: DSRVW-K* Ports: 32 RJ45
DECserver ConX4/ConX4P
Launched in 2004, the ConX4 offers comparable features to the DECserver 90M+ within a smaller chassis featuring four ports. It supports LAN speeds of 10/100 Mbps and port data rates up to 230.4 kbit/s.
Model number: DSC04-** Ports: 4 RJ45
Software Platform
All DECservers operate using DECserver Network Access Software (DNAS), which comprises multiple firmware images tailored specifically for different hardware variants. Each unit is preconfigured at the factory to request its corresponding firmware image upon startup.
In addition to terminal connectivity functions, newer DECserver models support reverse connection capabilities via LAT or Telnet protocols, allowing them to function as print servers or console servers.
Firmware File Details
During boot-up, DECservers retrieve designated firmware files through network requests:
| Terminal Server Model | Memory Requirements | Firmware Filename |
|---|---|---|
| DECserver 90L+ | none | Embedded PROM; no external firmware download required |
| DECserver 90TL | 1 MB | MNENG1.SYS / MNENG2.SYS (some references indicate a need for up to 4 MB) |
| DECserver 90M | between 1 and 2 MB | MNENG2.SYS / MNENG3.SYS |
| DECserver 90M+ | 4 MB | MNENG4.SYS |
| DECserver 100 | PS0801ENG.SYS | |
| DECserver 200 | PR0801ENG.SYS | |
| DECserver 250 | DP0601ENG.SYS | |
| DECserver 300 | SH1601ENG.SYS | |
| DECserver 500 | DS5node-name.SYS | |
| DECserver 700 | between 1 and over 2 MB | WWENG1.SYS / WWENG2.SYS |
| DECserver 900TM | WWENG2.SYS |
These firmware files are stored on Alpha, Itanium, or VAX systems running OpenVMS within SYS$SYSROOT:[MOM$SYSTEM], accessible via MOM$SYSTEM and MOM$LOAD logical names once DECnet communication is established.
For successful firmware loading during bootup, the hardware address of each device must be registered within the DECnet node database. The terminal server requests its specific firmware filename at startup; if this file is absent from MOM$SYSTEM, the boot process fails with an error message recorded on both the OpenVMS operator console and in SYS$MANAGER:OPERATOR.LOG.