Fiber project/IPTV multicast

Tim Jackson jackson.tim at gmail.com
Sat Feb 9 21:58:48 UTC 2013


Yes.

Most live IPTV is delivered across multicast*. There are a few gotchas.

MMR uses a unicast fill for instant channel change (configurable bandwidth
ammounts, etc) on top of Multicast. Some other middleware may have similar
methods to accomplish this.

Usually at the DSLAM you'll see "hax" to forward IGMP requests and
multicast ingress to/from a specific VLAN.

Most EFM based DSLAMs will segregate this all the way down to the CPE, and
let the CPE handle differentiating the joins on the particular VLANs.
Sometimes it's handled inside the DSLAM, but usually it's all configurable.

Handling live TV unicast is definitely possible but brings up another set
of challenges across the SP network towards the DSLAM/Agg point. Mainly
reproduction of the same content * subscriber count, so your bandwidth
towards a given DSLAM/Agg point grows with every subscriber. Low
penetration count of IPTV, this can be less bandwidth, as IPTV penetration
grows this could be several times the multicast bandwidth.

Usually most channel lineups are 1gbps->2.5gbps of multicast bandwidth,
depending on channel bitrates, amount of content, etc, etc..

MMR == Microsoft Mediaroom

--
Tim


On Sat, Feb 9, 2013 at 1:02 PM, Jay Ashworth <jra at baylink.com> wrote:

> Do any of the people who've worked with some of the IPTV delivery services
> mentioned here know if their live TV services can be handled via Multicast?
>
> Off-list replies are fine; will summarize if anyone else cares.
>
> Cheers,
> -- jra
>
> --
> Jay R. Ashworth                  Baylink
> jra at baylink.com
> Designer                     The Things I Think                       RFC
> 2100
> Ashworth & Associates     http://baylink.pitas.com         2000 Land
> Rover DII
> St Petersburg FL USA               #natog                      +1 727 647
> 1274
>
>



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