A fax server is simply a computer that has special software installed on it to enable all clients on a network to send and receive imaged documents. Instead of equipping all clients with a modem and fax software, users take advantage of the server’s capabilities to schedule and route faxes. In not having to equip every client machine with its own modem and fax software, the organization simplifies administration and saves money on software licenses.
Network Capabilities
Faxes can be delivered either directly to the recipient on the LAN or to another fax machine using the Public Switched Telephone Network (PSTN) or private WAN. For the cost of a local call, faxes also can be delivered to destinations worldwide using the Internet, an intranet, or an extranet.
Some fax servers offer redundancy and load-balancing features. Redundancy means that when one fax server fails, another fax server takes over its jobs. Load balancing means that jobs are directed to servers with available phones lines. This improves network performance by dynamically allocating bandwidth and fax channels among servers to prevent congestion at any single point on the network.
An optional fax-on-demand feature lets users dial into the fax server to retrieve documents. Users can call the server directly and request fax documents via a touch-tone telephone or request a fax document from a Web site by clicking on a hyperlink set up for that purpose.
Electronic mail gateway modules that can be added to fax servers to allow users to send, receive, and manage faxes through their e-mail boxes. They can gain access to their e-mail boxes remotely and use them as a universal collection point for faxes, as well as voice and e-mail messages. Some gateways support the most commonly used mail systems such as Lotus cc:Mail, Microsoft Mail, HP OpenMail, and Qualcomm’s Eudora, as well as the standard Internet mail server protocols SMTP, POP3, and IMAP.
A Web client module can be added to the fax server to permit corporate users to manage their fax mail boxes through all popular Web browsers, such as Netscape Navigator and Microsoft Internet Explorer. Whether they are at work, at home, or on the road, they can simply enter the Web address of the fax server for immediate access to all of their sent, received, and stored faxes.
A corporate fax server can be connected to an IP/PSTN gateway to allow documents to be sent over low-cost IP connections (Figure 44). IP faxes are like traditional faxes, except the Internet is used instead of the telephone network for at least some part of the transmission. The ITU T.38 standard defines a secure way to set up IP fax transmissions in real time.
A fax server can also be equipped for optical character recognition (OCR). With this module, fax documents are scanned for recognizable characters and converted into text files that can be imported into any application. Once there, users can edit the documents.
Administrative Features
Among the administrative features commonly found on fax servers are the following:
APPLICATION PROGRAMMING INTERFACE (API) Allows the administrator to integrate the fax capability with any of the desktop applications.
Figure 44
With a fax server connected to an IP/PSTN gateway, documents that start on the IP network are sent to the remote gateway where a local number is dialed to make the PSTN connection to a traditional fax terminal.
ACTIVE DIRECTORY INTEGRATION Supports ADSI-compatible (Active Directory Services Interface) networks, such as Windows NT 4.0, eliminating the need to maintain separate user databases.
WINDOWS NT AND NETWARE INTEGRATION Uses Windows NT and NetWare file and print services without burdening the server’s CPU.
SCALABILITY Allows the administrator to cascade (and load-balance) multiple fax servers to increase the number of available phone lines.
PARTIAL RETRANSMISSION When a fax transmission fails due to poor line quality or communication errors, the fax server automatically resends only the remaining pages.
FLEXIBLE INBOUND ROUTING Incoming faxes can be delivered directly to users’ mailboxes using direct inward dial (DID), ISDN, T.30 subaddressing, DTMF, line group routing, or manual routing.
CONFIDENTIALITY The administrator can grant users various privilege levels to ensure fax confidentiality.
TRANSACTION LOGS Provides real-time event information, including user name, recipient, fax number, destination, time sent, number of attempts, and duration of call.
BILLING Allows the administrator to configure and verify bill-back codes for accurate cost-analysis and tracking within the organization.
User Features
Among the user features commonly available from fax servers are the following:
FAX FROM ANY APPLICATION Enables users to fax from any application as easily as printing using the fax printer driver.
NATIVE ATTACHMENT SUPPORT Lets users fax any file in its native format by attaching it to a fax cover page.
OLE SUPPORT Allows users to fax documents in their native format. Object Linking and Embedding (OLE) prevents loss of data and ensures correct formatting of documents.
COVER-PAGE MANAGEMENT Users can select from multiple cover pages on the fly while typing the message. A cover-page editor lets users create and manage their own personal cover page.
MULTI-INDEXED PHONE BOOKS In addition to the corporate phone book kept on the server, users can maintain multiple personal phone books on their own computer, with all entries searchable by name, company, and fax number.
BROADCAST AND SCHEDULING Allows users to choose the recipients of a fax broadcast and set a time to start the broadcast.
INCOMING FAX NOTIFICATION Users receive notification of a new incoming fax through a pop-up message window that enables them to quickly view and print the fax.
FOLLOW-ME When users are out of the office, incoming faxes are automatically forwarded to another fax number or a designated colleague.
FAX STATUS Users are kept informed about the status of incoming and outgoing fax transmissions via color codes.
MIXED DISTRIBUTION Once a message is composed, it can be sent to a distribution list comprised of both fax and e-mail recipients.
Last Word
Fax servers make sending and receiving imaged documents as easy as sending e-mail. The fax capability can be added to an existing application server with appropriate software, or it can be a dedicated device that simply attaches to the LAN in UNIX, Windows, or Novell environments. Fax servers come in workgroup or enterprise configurations and functionality can be added with optional software modules available from the vendor. In handling faxes through a server, the organization can offer sophisticated capabilities more economically than equipping every client with its own hardware and software.
