> Another example, suppose I hire a trucking company to move some boxes from my house to yours.
> Does that give the trucking company the right to open the boxes, take stuff out, put other stuff
> in, or just not deliver the boxes because they are "just too busy"?
>
From http://help.twcable.com/html/twc_misp_aup.html

"The ISP Service may not be used in a manner that interferes with
Operator's efficient operation of its facilities, the provision of
services or the ability of others to utilize the ISP Service in a
reasonable manner. Operator may use various tools and techniques in
order to efficiently manage its networks and to ensure compliance with
this Acceptable Use Policy (“Network Management Tools”). These may
include detecting malicious traffic patterns and preventing the
distribution of viruses or other malicious code, limiting the number of
peer-to-peer sessions a user can conduct at the same time, limiting the
aggregate bandwidth available for certain usage protocols such as
peer-to-peer and newsgroups and such other Network Management Tools as
Operator may from time to time determine appropriate."


So in this case your landlord could check your mail to make sure that you
aren't a terrorist. And the movers could open your boxes to ensure you
weren't moving bombs[1].
The "boxes" are transparent.  They don't have to open them to look inside for the bombs.  There are also "sniffers" to check for explosive residue.  The "trucking" company can take any road they want.  But they must truck the "box" to the destination.  They still do not have the right to open the box, add or subtract from the contents, or not deliver "just because they are too busy".