David Diaz techlist at
Sat Nov 16 03:15:53 UTC 2002

At 16:01 -0800 11/15/02, Jere Retzer wrote:
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Some thoughts:

- Coast-to-coast "guaranteed latency" seems too low in most cases 
that I've seen. Not calling CEOs and marketers liars but the real 
world doesn't seem to do as well as the promises. As VOIP takes off 
"local" IP exchanges will continue/increase in importance because 
people won't tolerate high latency.  What percentage of your phone 
calls are local?

Well the bingo latency number used a lot in voice is 50ms.  Im 
simplifing without getting into all the details, but that's an 
important number.  As far as VoIP goes, I think higher latency is ok, 
it's more important to have "consistent" latency.  Fluctuating 
latency really affects VoIP more then a higher consistent latency. 
There are a lot of people doing VoIP and traditional voice on 
satellites and the latency there is huge.  Coast to coast latency on 
a good network is ~45 - 65ms depending on which customers you talk 
to.  Most phone calls are local as I mentioned in an earlier post so 
I do agree with you here that it would be a replacement for the 
traditional CO.

- Yes, we do various kinds of video over Internet2. Guess what? 
Packet loss is very important. Fewer hops mean fewer lost packets. 
Local exchanges, if there were lots of them with lots of peering 
reduces the theoretical number of hops. Who will most of the 
videoconferences involve in the future - I think mostly people who 
see each other face-to-face periodically. Leading this are telework 
and telemed. Broadband is getting to the point that people will want 
to call up their doc/clinic rather than jump in the car just to be 
told to go home and go to bed, and get exposed to someone who has a 
contagious disease. Nursing homes, assisted living facilities, 
emergency rooms in mall towns should be key targets for this 

Fewer hops = less packet loss?  There has been a lot of discussion on 
the list about that.  I still dont see it although it does push 
latency up a bit.  Truth is that there are a lot of tunnels or 
express routes build in, so we arent seeing all the hops nowadays.  I 
think that's more for sales and marketing as people keep judging 
networks by hops in a traceroute.

- While we're on the topic of local video, what happens when 
television migrates to IP networks?  Seems like the "local" 
news should want to originate somewhere close. Most of our local TV 
and radio stations are part of chain today and their corporate 
headquarters have decided to host their web site at a central 
location without even worrying about Akamai or other local caching.

An IP backbone is a bad place for live TV.  Delayed or on demand tv 
yes.  Live tv plays to the benefits of One to Many broadcast ability 
of satellite as Doug Humphrey will tell you.  So a feed from a DSS 
dish into your local cache would work well.  It still can be done at 
a per city peering point to better feed the broadband users.  Its the 
simplest solution probably although I know someone will mention 
multicast here...

Actually I find it interesting that the movie industry is taking the 
initiative and putting up a website to do streaming movies for free 
to users.  They are trying to learn from the mistakes of the music 
industry.  Perhaps this is the killer app since it's one to one 
transmission over the IP backbone.  It would be ironic if hollywood 
trying to avoid video theft drove peering and IP growth.... 
interesting world we live in.

Have a nice weekend.

- Unfortunately, these applications do not work with today's local 
broadband networks - one reason being the lack of local 
interconnection. People have quit believing the Radio Shack ads. We 
have the technology to make these applications work if we'd stop 
arguing that no one wants to use them. Of course no one wants to use 
them - they know they won't work!

>>>  David Diaz <techlist at> 11/14/02 05:52PM >>>

Voice of reason...

The only possible reason I can think of is if these data networks
replace the present voice infrastructure.  Think about it, if we
really all do replace our phones with some video screen like in the
movies, then yes, most of those calls stay local within the cities.
Mom calling son etc etc

So we can think of these "peering centers" as replacements for the
5-10 COs in most average cities.

Otherwise what apps require such dense peering.

At 14:44 -0800 11/14/02, Vadim Antonov wrote:
>On Thu, 14 Nov 2002, David Diaz wrote:
>>   2) There is a lack of a killer app requiring peering every 100 sq Km.
>Peering every 100 sq km is absolutely infeasible.  Just think of the
>number of alternative paths routing algorithms wil lhave to consider.
>Anything like that would require serious redesign of Internet's routing
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