<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><div>On 27/04/2010, at 11:09 AM, Narelle wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div>On Thu, Apr 22, 2010 at 10:05 AM, Daniel Hood <<a href="mailto:dsmhood@gmail.com">dsmhood@gmail.com</a>> wrote:<br><blockquote type="cite">They are putting in a multicast network?<br></blockquote><blockquote type="cite"><br></blockquote><font class="Apple-style-span" color="#006312"><br></font>NBN Co, from what I can unravel so far, is intending to use some of<br>the newer features in GPON gear to make it multicast aware. I'm still<br>struggling with how this would work, and have some concerns about the<br>stability and interoperability of any such implementation. The<br>intention is to facilitate IPTV.<br></div></blockquote></div><div><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><br><div>One of the implementations I've worked with before had the concept of a per-customer "multicast whitelist".</div></div></div></span></span></div><div><br class="webkit-block-placeholder"></div><div>The idea is that CPE can then only join authorised multicast groups, which makes selling PayTV or premium content possible.</div><div><br></div><div>(Apologies if the relevant working groups have already discussed the following)</div><div><br></div><div>The technical parts have been solved before, the questions are going to be things like:</div><div><br></div><div>- how do we update a whitelist</div><div>- will a multicast group be per-provider, or per region</div><div>- if the former, who will run a multicast peering exchange or multicast transit service (didn't the Worldcom one get dismantled years ago)?</div><div>- do we need an industry standard DRM for distributing content in a way that keeps its owners happy and networks cheap</div><div>- do we want IGMPv3 for fast channel changes, or do we just 'waste' the available bandwidth</div><div>- will it be possible to cause a denial of service on your neighbourhood PON by joining too many HDTV multicast groups simultaneously</div><div>- will existing cable providers end up with an RF overlay on the fibre so they can preserve 1.6M+ installed set-top-boxes</div><div><br></div><div>John</div><div><br></div></body></html>