cation image being printed. The performance depends on the balance away from the office. between PC software capability, for example speed of compression, Development continues in CCITT with higher speed, higher res- and the processing and memory capability of the card itself. olution transmission and with high speed character and mixed mode User expectations that the simple operation of fax machines be functions. available in PC fax are beginning to be met together with back- The potential for communication with this ubiquitous terminal is ground operation of the PC in fax mode. However there are similar hardly touched. Interfaces into the facsimile domain to use the incoming document problem as for gateways: proven reliable transmission method are increasing. The terminals provide reliable input/output devices into other applications and 1. Difficult to provide adequate soft copy memory. systems using the current CCITT recommendations. Continued 2. Slow to print received pages. growth in the number of terminals, including the domestic environ- 3. Limitations of screen resolution or of whole page display. ment is expected. 4. Time to decode/display compressed image limits search mode. One of the benefits of PC fax cards or fax gateways is their ability Bibliography to send the equivalent of personalised mailshots by facsimile, a feature not normally available in the broadcast mode of facsimile CCITT (1989) Blue Book Volume VII Fascicle VII.3, International transceivers which send identical documents to all destinations. Telecommunication Union, Geneva, ISBN 92- 61-03611-2 The fax modem fitted to these cards can also be used for PC to PC Costigan, D.M. (1971) The principles and practice of Facsimile communication for file transfer over the PSTN. If the growth in this Communication, Philadelphia, Chilton. requirement continues, then discussions in CCITT are likely to provide an additional option within the G3 fax recommendations. Halton, Jones and Treece (1991) Facsimile - the essential image, The convenience of c