[Bloat] [aqm] ping loss "considered harmful"

David Lang david at lang.hm
Mon Mar 2 18:14:58 EST 2015

On Mon, 2 Mar 2015, Joe Touch wrote:

> On 3/2/2015 1:40 AM, Brian Trammell wrote:
> ...
>> The real solution is to create a utility called "ping" that uses
>> traffic that gets prioritized the same way as the traffic you care
>> about instead of ICMP echo request/reply. Users don't care about
>> the packets on the wire so much as they do that you're supposed to
>> ping things.
> There are three separate problems:
> 1. a ping that doesn't use ICMP
> 	there are dozens of these
> 2. needing a reflector
> 	ping gets around this only because the reflector is widely
> 	deployed (and integrated into most OSes)
> 3. using the same port as the traffic you care about
> 	transport protocol is only one problem (ICMP being a "transport
> 	protocol" by virtue of using the IP protocol number field)
> 	the other is differential prioritization based on port number
> 	there's no easy solution to that;
> 	every service would need an integrated
> 	ping reflector
> I suspect #3 is the ultimate killer of this idea.

The service you are trying to contact acts as a reflector for TCP traffic. If 
you send a syn you will get back a syn-ack from the TCP stack of the receiving 

For UDP systems, it gets more interesting and service specific. But for TCP 
systems it works today.

David Lang

More information about the Bloat mailing list