This note describes the features and changes expected to be part of of HylaFAX Version 4.0. The first public beta version of HylaFAX v4.0 is planned for late February or early March, 1996. As usual the announcement of its availability will be posted to the flexfax-announce@sgi.com mailing list (which is also fed to the flexfax@sgi.com list). Information on subscribing to these mailing lists is available here.

The following is an abbreviated list of new functionality that is to be part of the released version of HylaFAX 4.0. All items not marked as incomplete will be present in the first beta distribution.

• Completely redesigned client-server protocol with full support for submitting, managing, and querying the status of outbound facsimile jobs and notification, administration, and retrieval of received facsimile
• Optional support for the old client-server protocol (configurable at build time and at runtime) for use with old HylaFAX- and FlexFAX-compatible clients
• Revised and more flexible security measures for controlling client access to server systems
• Extended job queueing model whereby outbound jobs that terminate are not immediately purged from the server (or their documents) for the purpose of job archival and/or job resubmission
• Hooks for automatically archiving outbound jobs on the server system (full support is not planned)
• Rearchitecture of the client and server software to simplify the support of multiple transport protocols
• Server support for transcoding of inbound and outbound TIFF (e.g. it is possible to store all received facsimile MMR-encoded to minimize space)
• Server support for automatically truncating trailing whitespace in outbound facsimile
• Support for SUB (SUbAddress), SEP (SElectivePolling), and PWD (Password) frames in the Class 1 driver and in future ITU T.Class2-compliant modems

HylaFAX 4.0 is a significant rearchitecture of the v3.0 software. Most importantly, the client-server protocol has been totally redone using elements of the ITU T.611 specification for the ``APPLI/COM'' Programming Communication Interface (PCI) and the Internet File Transfer Protocol (FTP). This new protocol is intended to provide a strong framework in which fax-aware client applications can make use of fax services in a network environment. The protocol is intended to be both sufficient and reasonably complete; no additional services are required such as a network file access protocol (as required by T.611).

An effect of the new client-server protocol is a change in the model for handling outbound jobs and document resources. In the past jobs and documents submitted to a server were assumed to reside on the server only so long as a job was actively being scheduled and/or processed. Under the new system the server can be considered a repository for documents, and jobs are treated as more long-lived objects whose scheduling can be controlled on a more fine-grained basis. Specifically, documents and jobs may persist after the time that a job has terminated and documents may reside on a server independent of any association with a job. These changes make it possible for clients to do things like resubmit failed jobs using previously transferred documents; forward received facsimile without transferring documents through a client's system; and implement job archival mechanisms. The more fine-grained scheduling control of jobs permits clients to more easily manage and control submitted jobs; it is now possible for a client to suspend a job, alter its contents in some complex way, and then resubmit it to the scheduler.

HylaFAX 4.0 will be distributed in source and binary form by public ftp on the Internet. Full binary distributions for all ``supported platforms'' are intended to be available at the same time as the source distribution. Source distributions that are built with the GNU gcc compiler must use gcc version 2.6.1 or later. As noted above, availability of distributions will be posted to the flexfax-announce and flexfax mailing lists.

HylaFAX table of contents.