Multicast Groups Assignments

In this blog we will look at multicasts group assignments.

In short, I'm kind of famous in that I registered a few multicast groups in a few past life. If you google multicast and either kfelix @ pcquote or hyperfeed,  you will find  multicast groups assigned  and registered by myself.

i.e

• 224.0.1.120 { hyperfeed ,  now registered for spryware  }
• 224.0.19.240-224.0.19.255  { hyperfeed }

These groups where allocated via IANA back in the late 90s. My name was even listed in a few cisco documents and materials, as was pointed out by a few associates of mine when reviewing some study materials.

To register a group(s) with IANA, they only required a few brief line and description of the purpose of the groups. The groups listed above, where for distribution of multicast market data feeds btw. The cost after justification for the group is ;  $0.00 dollars ( FREE ).

Multicast groups registering is kinds of pointless imho, since you have no really Authoritive controls for the enforcement of groups address within applications usages. Since the internet does not  support multicast natively,  this problem becomes mute.

Back in the late 90s we investigated using sprint's multicast enable internet services. You had the option to enable  your uplink as a multicast leaf with the sprint-network. No controls where presented for rate-limiting or restricting group registration at that time. I'm sure this has changed by now. So person or org that want to  publish to your multicast destination address, could do so. And all subscribers within  that multicast branch would received the traffic.

To get the current listing  of mcast-group assignments for ipv4 an ipv6 , you can visit  IANA website.

http://www.iana.org/assignments/multicast-addresses/multicast-addresses.xhtml

and

http://www.iana.org/assignments/ipv6-multicast-addresses/ipv6-multicast-addresses.xhtml


Ipv6 registration has better controls and by defining both site and  node local. But the same problems with  enforcement becomes a issue as it pertain to the global internet.

To learn about sprint multicast, please review the  FAQs ( as far as I know they are the only north-american ISP that offers multicast to any sprint  internet  routed customer )


https://www.sprint.net/index.php?p=faq_multicasting

 Turn around is only a email after you have established internet-uplinks and takes approx 2-4 days.



Ken Felix
Freelance Network/Security Engineer
kfelix -a-t  socpuppets-d-o-t- com