Performance Implications of Link Characteristics

Document Charter Performance Implications of Link Characteristics WG (pilc)
Title Performance Implications of Link Characteristics
Last updated 2004-01-08
State Approved
WG State Concluded
IESG Responsible AD (None)
Charter Edit AD (None)
Send notices to (None)


Erik Nordmark ( is the Technical Advisor.

The Internet network-layer and transport-layer protocols are
designed to accommodate a very wide range of networking
technologies and characteristics.  Nevertheless, experience has shown 
that the particular properties of different network links can have a 
significant impact on the performance of Internet protocols operating 
over those links, and on the performance of connections along paths 
include such links.  This is especially of concern to the wireless 
networking community.

The PILC working group will produce several BCP/Informational
documents.  The first document will discuss considerations for 
link-layer designers from the perspective of best supporting existing 
IETF protocols will be produced.  The next document will discuss the 
capabilities, limitations and pitfalls of 'performance enhancing 
proxies' (PEPs), that is, active network elements that modify or splice 
end-to-end flows in an attempt to enhance the performance they attain 
the face of particular link characteristics.  The remaining documents 
will either discuss the impact and mitigations for a problematic
link-layer characteristic (or group of closely related 
or provide overviews of which other PILC documents apply to particular 
problem domains.

As one of its first work items, the WG will review an existing
I-D on considerations for "long, thin" networks (one of the salient
characteristics of terrestrial wireless links).  This will be
published as a preliminary assessment of the problem domain, to
be refined by later PILC documents.

All documents will identify which of their considerations remain
research topics versus which are established as advanced
development.  Research topics will be explicitly flagged as not
part of any recommendations.  All documents will also identify
any security implications associated with their considerations.

The working group will also serve as a forum for discussing
possible modifications to IETF protocols to improve performance
in environments with problematic link characteristics - however,
not to the detriment of performance and stability in the general
Internet, nor to undermine existing security models.

It is incumbent upon the chairs to ensure that the WG maintains
good communications with other groups interested in related
technology issues, such as wireless forums.