| Infrastructure servers provide support for wide area | | | | optional parameters are consistent, and remote help |
| network (WAN) communications. This support | | | | desk operators are aware of them. This simplifies the |
| typically includes support for a subset of IBM System | | | | analysis that must occur to provide support. Sharing |
| Network Architecture (SNA), asynchronous protocols, | | | | information, such as word processing documents, is |
| X.25, ISDN, TCP/IP, OSI, and LAN-to-LAN NetBIOS | | | | easier when everyone is at the same release level |
| communication protocols. In the Novell NetWare | | | | and uses the same default setup within the software. |
| implementation, Gateway Communications provides a | | | | Central productivity services such as style sheets and |
| leading communications product. In the LAN Server | | | | macros can be set up for general use. Most personal |
| and LAN Manager environments, OS/2 | | | | productivity products do permit local parameters such |
| communications server products are available from | | | | as colors, default printers, and so forth to be set |
| IBM and DCA. In the Banyan VINES environment, the | | | | locally as well. Backups of the server can be |
| addition of DCA products to VINES provides support | | | | scheduled and monitored by a trained support person. |
| for SNA connectivity. UNIX servers provide a range | | | | Backups of client workstations can be scheduled |
| of product add-ons from various vendors to support | | | | from the server, and data can be stored at the |
| the entire range of communications requirements. | | | | server to facilitate recovery. Tape or optical backup |
| VMS servers support Decent, TCP/IP, and SNA as | | | | units are typically used for backup; these devices can |
| well as various asynchronous and serial | | | | readily provide support for many users. Placing the |
| communications protocols. MVS servers provide | | | | server and its backups in a secure location helps |
| support for SNA, TCP/IP, and some support for | | | | prevent theft or accidental destruction of backups. A |
| other asynchronous communications. Security at the | | | | central location is readily monitored by a support |
| server restricts access to software and data | | | | person who ensures that the backup functions are |
| accessed from the server. Communications access is | | | | completed. With more organizations looking at |
| controlled from the communications server. In most | | | | multimedia and image technology, large optical |
| implementations, the use of a user login ID is the | | | | storage devices are most appropriately implemented |
| primary means of security. Using LAN Server, some | | | | as shared servers. High-quality printers, |
| organizations have implemented integrated Response | | | | workstation-generated faxes, and plotters are natural |
| Access/Control Facility (RACF) security by creating | | | | candidates for support from a shared server. The |
| profiles in the MVS environment and downloading | | | | server can accept input from many clients, queue it |
| those to the LAN server for domain control. Systems | | | | according to the priority of the request and handle it |
| and network management services for the local LAN | | | | when the device is available. Many organizations |
| are managed by a LAN administrator, but WAN | | | | realize substantial savings by enabling users to |
| services must be provided from some central | | | | generate fax output from their workstations and |
| location. Typically, remote LAN management is done | | | | queue it at a fax server for transmission when the |
| from the central data center site by trained MIS | | | | communication costs are lower. Incoming faxes can |
| personnel. The discussion in the following sections | | | | be queued at the server and transmitted to the |
| more specifically describes the functions provided by | | | | appropriate client either on receipt or on request. In |
| the server in a NOS environment. Requests are | | | | concert with workflow management techniques, |
| issued by a client to the NOS services software | | | | images can be captured and distributed to the |
| resident on the client machine. These services format | | | | appropriate client workstation from the image server. |
| the request into an appropriate RPC and issue the | | | | In the client/server model, work queues are |
| request to the application layer of the client protocol | | | | maintained at the server by a supervisor in concert |
| stack. This request is received by the application | | | | with default algorithms that determine how to |
| layer of the protocol stack on the server. File | | | | distribute the queued work. Incoming paper mail can |
| services handle access to the virtual directories and | | | | be converted to image form in the mail room and |
| files located on the client workstation and to the | | | | sent to the appropriate client through the LAN rather |
| server's permanent storage. These services are | | | | than through interoffice mail. Centralized capture and |
| provided through the redirection software | | | | distribution enable images to be centrally indexed. This |
| implemented as part of the client workstation | | | | index can be maintained by the database services for |
| operating environment. | | | | all authorized users to query. In this way, images are |
| To diminish the effort and effect of installation and | | | | captured once and are available for distribution |
| maintenance of software, software should be loaded | | | | immediately to all authorized users. Well-defined |
| from the server for execution on the client. New | | | | standards for electronic document management will |
| versions can be updated on the server and made | | | | allow this technology to become fully integrated into |
| immediately available to all users. In addition, | | | | the desktop work environment. There are dramatic |
| installation in a central location reduces the effort | | | | opportunities for cost savings and improvements in |
| required for each workstation user to knob the | | | | efficiency if this technology is properly implemented |
| installation process. Because each client workstation | | | | and used. Article 10 discusses in more detail the |
| user uses the same installation of the software, | | | | issues of electronic document management. |