A number of IETF efforts have developed or are developing different 
forms of reliable (and often "lightweight") transport protocols, because 
they perceive that TCP is inadequate for their requirements.  This BOF 
will explore what those requirements are, serving both as input into a 
TSV directorate document discussing the services that can be built on 
top of TCP; and to gauge the utility of developing a transport protocol 
(perhaps a TCP variant) and/or session protocol that can meet these 
needs in a general way.

The focus is on clear-and-present requirements for unicast and reliable
(or "near-reliable") transport/sessions, and not on general transport
protocol features, nor on specific alternative transport protocols 
(except as they illustrate requirements).