IBM LAN Server

The IBM LAN Server started as a close cousin of Microsoft LAN Manager and first shipped in early 1988. It was originally designed to run on top of Operating System/2 Extended Edition. The network client was called "IBM LAN Requester" and was included with OS/2 EE 1.1 by default. (Eventually IBM shipped other clients and supported yet more. Examples include the "IBM OS/2 File/Print Client", "IBM OS/2 Peer", and client software for Microsoft Windows.) Here the short term "LAN Server" refers to the IBM OS/2 LAN Server product. There were also LAN Server products for other operating systems, notably AIX (now called Fast Connect) and OS/400.
Version history.
Predecessors included IBM PC LAN Program (PCLP). Variants included LAN Server Ultimedia (optimized for network delivery of multimedia files) and Workplace On-Demand. Add-ons included Directory and Security Server, Print Services Facility/2 (later known as Advanced Printing), Novell NetWare for OS/2, and LAN Server for Macintosh.
Innovations.
LAN Server pioneered certain file/print sharing concepts such as domains (and domain controllers), networked COM ports, domain aliases, and automatic printer driver selection and installation.