The Forum consists of two standardization organizations (the Association of Radio Industries and Businesses [ARIB] and the Telecommunication Technology Committee [TTC]), 19 managing companies and 72 general member companies.
The fifth General Assembly brought together representatives from the majority of the members, including Mr. Shoichiro Asano, PIAF Chairman and Professor of National Center for Science Information Systems. After having approved the activities in 1997, the participants exchanged views on PIAF’s activity plan in the fiscal year 1998.
They approved the technical documents of the Real-time Protocol that will enable transmission of moving pictures via 32k PIAFS (PIAF Standard), which was one of the works in 1997. They also agreed upon setting the technical standard of 㦬k PIAFS,” a data transmission system for enabling access to the Internet at 64 kbit/s. Specifications for 64k PIAFS are planned for completion in 1998.

Outline of PIAFS Real-time Protocol
In 1996, PIAF established PIAFS as the technical standard for end-to-end data transmission via PHS. (See PHS MoU Group News No. 6, October 1996 for detailed explanation of PIAFS.)
Since then, PIAF continued its researches into real-time protocols to identify the best-suited protocol for near real-time moving picture transmission. It has subsequently compiled the technical documents for PIAFS Real-time Protocol.
PIAFS Real-time Protocol is used for communications between two multimedia terminals connected respectively to a PHS terminal, and for communications between a multimedia terminal connected to a PHS terminal and another multimedia terminal incorporating PIAFS Real-time Protocol that is linked to an ISDN network.
As described in ITU-T Recommendation H.324/AnnexC, PIAFS Real-time Protocol transmits multiplexed moving picture and voice data for real-time communications. This protocol also protects against transmission errors. Fig. 1 shows an example of a system incorporating PIAFS Real-time Protocol.
Features of the PIAFS Real-time Protocol are as follows:

1) The PIAFS In-band Negotiations part determines which protocol, PIAFS Data Transmission Protocol or PIAFS Real-time Protocol, is to be used in data transmission. Real-time Protocol is used selectively.
2) PIAFS Real-time Protocol is in conformity with Recommendation H.223 Annex A/B/C that was approved at ITU-T meeting in February, 1998. This Recommendation gives references for several protocol levels: For Level 0 (equivalent to H.223), installation of PIAFS Real-time Protocol in terminals is compulsory; and for upper Levels from 1 to 3, installation is optional.
3) According to the specifications, PIAFS Real-time Protocol functions as an adaptation layer, providing a frame structure suited for real-time transmission via PHS and an error detection and correction function. The specifications do not cover video CODEC for moving pictures and audio CODEC for voice, because they are defined as applications to run on the adaptation layer. H.263, MPEG-4 and other existing protocols, as well as application protocols to be adopted in future, function as adaptation layers.
Fig. 2 shows an example of system configurations for multimedia terminals incorporating Real-time Protocol.
In line with the compilation of PIAFS Real-time Protocol specifications, some revisions have been made accordingly to PIAFS Data Transmission Protocol specifications.