Detection time in demand mode

roggie-bfd@sohu.com Sun, 20 March 2005 12:13 UTC

From: roggie-bfd@sohu.com
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Date: Sun, 20 Mar 2005 20:12:22 +0800
To: dkatz@juniper.net
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Subject: Detection time in demand mode
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Dave,
  In section 6.7.4 , it said :
   In Demand mode, the Detection Time calculated in the local system is
   equal to bfd.DetectMult, multiplied by the agreed transmit interval
   (the greater of bfd.RequiredMinRxInterval and the last received
   Desired Min TX Interval.)  bfd.DetectMult is (roughly speaking, due
   to jitter) the number of packets that have to be missed in a row to
   declare the session to be down.
  From the above sentence , i get the flowing conclosion , for example :
  A------------------B
DM=3                DM=1
MTI=100ms           MTI=10ms
MRI=20ms            MRI=200ms
  if A sends a poll sequence , the transmit interval is 200ms[max(100ms,200ms)] , 
  the detection time is 60ms[3*max(20ms,10ms)] , is it correct??

  another question : in the spec , it always said "If Demand mode is not active" ,
  i wants to ask is it the flowing meaning if one side set to demand mode and 
  the other side dose not set , the side setted to demand mode also MUST send 
  period control packet ? i am not sure !

Thanks
Roggie

Detection time in demand mode roggie-bfd
Re: Detection time in demand mode Dave Katz