So - when I first got fiber optic from CenturyLink, they had a IPTV (Internet protocol TV) service called Prism. It was great!
Basically - they used multicast for all of their TV channels. This effectively meant that you could watch TV over your fiber optic system without losing any of the bandwidth you were paying for. I know - I used to fire up the three Prism boxes I had, and then run network speed tests. Add to this the original IPoE (Internet Protocol over Ethernet) configuration of the fiber optic boxes - necessary for multicast support - and it was a potent system. Almost no latency or lag. Sadly - they abandoned the whole Prism infrastructure and converted us to PPPoE to gain the TV bandwidth back. Cheers, Paul > On Dec 24, 2024, at 5:14 PM, Steve VanDevender > <[email protected]> wrote: > > 'Doug Elrod' via World News Now Discussion List writes: >> When I hear about football games being streamed (such as on >> Christmas, tomorrow), and the fact that apparently a Thursday night >> game took 30% of the Internet bandwidth (however that is measured >> :-)), I wonder if somehow the Multicast Protocol (which I read >> about decades ago) is not being used. From what I remember, it's >> like shouting to everyone (say UDP), rather than requiring >> handshaking with everyone individually (like TCP). > > In the earlier days of the Internet when bandwidth was limited, IP > multicast was pretty intensively researched as a way to stream live > content with less bandwidth usage. The main savings was that a single > copy of the multicast data could be sent on a common link shared by a > number of receivers; at a point where there were multiple networks > containing recievers of multicast data, the single copy on a shared > upstream link would be copied into each of the downstream links. This > meant routers had to dynamically track when members of a multicast > session existed in networks connected to them and share that > information with other routers involved in that session. Consequently > routing multicast packets is much more complicated than normal IP > routing, which in principle needs only to track which destination > addresses are reachable via connected networks. > > Multicast is actually handled as as particular address range whose > addresses are used for multicast groups (224.0.0.0 through > 239.255.255.255 are reserved for multicast in IPv4) and with some > additional protocols like IGMP (Internet Group Management Protocol) > for passing around information about multicast group membership. > Multicast also used only UDP for data transmission since the > individual session handling of TCP doesn't fit well with multicast > routing. > > The only major advantage of using multicast for streaming was reduced > bandwidth usage on Internet backbone links, which was a concern in the > early 1990s when bandwidth was in shorter supply and there were > concerns that routers weren't going to be able to keep up with > explosive growth in the number of networks connected to the Internet. > It was also like broadcast radio or television in that audio or video > streamed by multicast could only be live. While it was entirely > possible to stream movies or television shows on multicast, it would > have to be on a schedule so you couldn't start watching a movie or > show from the beginning whenever you wanted. > > Since the original concerns about bandwidth and router limitations > were solved, streaming over regular UDP or TCP became standard. Even > though it does use more bandwidth, it's much more flexible than > multicast streaming and actually takes less complicated routing > infrastructure. > > There are still some applications besides audio or video streaming > where multicast is still used. > >> I guess if you want to personalize ads you need the extra >> bandwidth, but it seems incredibly wasteful, IMHO. > > If multicast had taken off I'm sure they would have found a way to do > this in multicast, much as how ad time is divided between the national > network and slots where local affiliates can insert their own ads into > broadcasts. > >> -Doug Elrod ([email protected]) > > -- > You received this message because you are subscribed to the Google Groups > "World News Now Discussion List" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion visit > https://groups.google.com/d/msgid/wnndl/26475.12879.403581.468354%40hexadecimal.uoregon.edu. -- You received this message because you are subscribed to the Google Groups "World News Now Discussion List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/d/msgid/wnndl/0331A7A6-038E-49E0-A807-B28DE7862E28%40hotmail.com.
