[Chicago-talk] Speakers needed

[John Kristoff]

On Wed, Jan 30, 2013 at 12:34:37PM +0000, Sean Blanton wrote:
> I can talk about multicast and pad it with related trivia
> (IO::Socket::Multicast, Net::Pcap, Net::Frame::Layer, network
> protocols - stuff like that). Multicast is a great tool and I think
> more people would use it if they knew about it.

Hi Sean,

This would be an interesting topic and I'd tried to attend if I could
(my first ever).

However, having done lots of IP multicast over the years at both
depaul.edu, northwestern.edu and cooperation with the global Internet
multicast-enabled community, I'm going to rain on your parade a bit.
Inter-domain multicast has never gained much traction outside a few
niche areas even after years and years of a few dedicated people trying,
yours truly included, and I doubt it ever will.

Judging by your email address, I suspect you may have it deployed within
an organization, where high-volume "hoot-n-holler" and ticker apps can
readily take advantage of it.  Northwestern has made significant use of
it internally for cable TV to dorms where it was too expensive to
rewire.  A number of networks have also used it for PC imaging (e.g.
Norton Ghost).

These are good use cases, but wide deployment of Internet multicast
appears to be largely dead and possibly rightfully so.  Part of the
reason is the fundamental change in how the network has to setup and
maintain forwarding to groups.  It is almost completely upside down from
traditional unicast-based routing.  If you've never operated networks
before, believe me I could go on an on about how non-trivial this is
from a protocol perspective, a vendor equipment perspective, a network
operator support perspective and a security perspective.

Nonetheless, I too have found Net::Pcap as well as related modules such
as NetPacket, Net::Packet, Net::DNS, Net::SSLeay and the various generic
Socket modules both helpful and useful for lots of work.  I'm certain I
could pick up some good information from you talk, so please do it, even
if I'm not so encouraged by IP multicast these days.  In fact, I'm
downright disgruntled with the injuries to prove it.  :-)

Joh