Assurred Services

Hi,
  Recently I read some presentation slides at 
http://www.iam.unibe.ch/~braun/talks/swisscom498/ppframe.htm
  on "Differentiated Services of Internet". 
  I am confused with the statements about "Assured Services" 

  1) Users/ISP negotiate service profile
  2) No QoS guarantees but low loss probability
  3) Pkt which dont conform to the service will not be dropped but
     will be made best effort. 

  I see the stmt 2) quite not fitting with others. Am I missing
something ? 

Thanks
Dhiman Barman
Boston Univ 
PhD student
Dept of Computer Science.
-- 
If you only have a hammer, you tend to see every problem as a nail.
                -- Maslow