Path: utzoo!attcan!uunet!wuarchive!usc!ucsd!pacbell.com!tandem!zorch!xanthian From: xanthian@zorch.SF-Bay.ORG (Kent Paul Dolan) Newsgroups: comp.sys.amiga Subject: Re: CDTV Idea! Keywords: CDTV,Networking,Cable Message-ID: <1990Jul11.155246.22314@zorch.SF-Bay.ORG> Date: 11 Jul 90 15:52:46 GMT References: <9350@life.ai.mit.edu> <5908@hub.ucsb.edu> <2695@awdprime.UUCP> Distribution: na Organization: SF Bay Public-Access Unix Lines: 38 Well, it looks like all the pieces are here to make this work, though possibly in an optional appliance sold to sit alongside the CDTV box: 1) a writeable laser recording the same format as the CDTV reads; 2) a cable channel or channel interframe gap (depending on how fast you have to download this stuff to satisfy customers' demands) to pass the information down quickly; half an hour at full speed will fill the biggest video disk; 3) the pay for view system to capture recording requests, with the bill recorded when the program has been successfully received and validated; 4) error correcting bits with each track of data (I've seen ECC used that could correct a 200 bit burst of noise in a 32K bitstream), and multiple transmission of each track spread out in time to get past longer noise bursts; 5) frequent menus of available programs; if the system worked like HBO and broadcast the same program several times in a week, and it used just the interframe gap, the main picture portion could alternate between demos/sales pitches for the programs, and order menus/instructions, simultaneous with the actual program data transmission taking place in the gap, and the user could program a list of programs to capture without worrying about their order. This doesn't require two way communication, which simplifies some of the concerns. With a suitable encoding of each transmitted track or block of program, it would even be possible to have data for all the programs be broadcast mixed together in an endless loop, and picked up in fairly random order one or more programs at a time, and sorted out by system software onto the target disk(s). Don't you love designing technology interactively on the net? Building castles in the air, it's called elsewhere. Kent, the man from xanth. -- Trish, condemned to a future of living behind the seven eleven -- Mark Smith