[Tinyos-2-commits] CVS: tinyos-2.x/doc/txt tep126.txt,1.1,1.2

[Phil Levis]

Update of /cvsroot/tinyos/tinyos-2.x/doc/txt
In directory sc8-pr-cvs10.sourceforge.net:/tmp/cvs-serv30011/txt

Modified Files:
	tep126.txt 
Log Message:
TEP 126


Index: tep126.txt
===================================================================
RCS file: /cvsroot/tinyos/tinyos-2.x/doc/txt/tep126.txt,v
retrieving revision 1.1
retrieving revision 1.2
diff -C2 -d -r1.1 -r1.2
*** tep126.txt	23 Mar 2007 16:48:07 -0000	1.1
--- tep126.txt	4 Apr 2007 03:14:21 -0000	1.2
***************
*** 399,433 ****
  power consumption:
  
! 1. Invalid Packet Shutdown
!   Typically, packets are filtered out by address at the radio hardware
!   level.  When a receiver wakes up and does not receive any
!   packets into the low power listening layer of the radio stack, it 
!   will automatically go back to sleep after some period of time.  As a 
!   secondary backup, if address decoding on the radio chip is disabled, 
!   the low power listening implementation will shut down the radio if 
!   three packets are receive that do not belong to the node.  This helps 
!   prevent against denial of sleep attacks or the typical transmission 
!   behavior found in an ad-hoc network with many nodes.
! 
! 2. Early Transmission Completion
!   A transmitter typically sends a packet for twice the amount of time
!   as the receiver's receive check period.  This increases the probability
!   that the receiver will detect the packet.  However, if the transmitter receives
!   an acknowledgement before the end of its transmission period, it
!   will stop transmitting to save energy.  This is an improvement
!   over previous low power listening implementations, which transmitted
!   for the full period of time regardless of whether the receiver has 
!   already woken up and received the packet.
  
! 3. Auto Shutdown
!   If the radio does not send or receive messages for some period of
!   time while low power listening is enabled, the radio will automatically 
!   turn off and begin duty cycling at its specified duty cycle period.
  
! 4. CCA Sampling Strategy
!   The actual receive check is performed in a loop inside a function, 
!   not a spinning task.  This allows the sampling to be performed
!   continuously, with the goal of turning the radio off as quickly as 
!   possible without interruption.
  
  
--- 399,433 ----
  power consumption:
  
!    1. *Invalid Packet Shutdown:*
!    Typically, packets are filtered out by address at the radio hardware
!    level.  When a receiver wakes up and does not receive any
!    packets into the low power listening layer of the radio stack, it 
!    will automatically go back to sleep after some period of time.  As a 
!    secondary backup, if address decoding on the radio chip is disabled, 
!    the low power listening implementation will shut down the radio if 
!    three packets are receive that do not belong to the node.  This helps 
!    prevent against denial of sleep attacks or the typical transmission 
!    behavior found in an ad-hoc network with many nodes.
  
!    2. *Early Transmission Completion:*
!    A transmitter typically sends a packet for twice the amount of time
!    as the receiver's receive check period.  This increases the probability
!    that the receiver will detect the packet.  However, if the transmitter receives
!    an acknowledgement before the end of its transmission period, it
!    will stop transmitting to save energy.  This is an improvement
!    over previous low power listening implementations, which transmitted
!    for the full period of time regardless of whether the receiver has 
!    already woken up and received the packet.
  
!    3. *Auto Shutdown:*
!    If the radio does not send or receive messages for some period of
!    time while low power listening is enabled, the radio will automatically 
!    turn off and begin duty cycling at its specified duty cycle period.
!  
!    4. *CCA Sampling Strategy:*
!    The actual receive check is performed in a loop inside a function, 
!    not a spinning task.  This allows the sampling to be performed
!    continuously, with the goal of turning the radio off as quickly as 
!    possible without interruption.