Serval question! Thanks!!
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Subject: Serval question! Thanks!!
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Dave, 1、The transmmit interval is at least 1s before the session is UP , i am not sure does the vlaue set to the BFD control packet! if does and at what time does the BFD control set the actual value to the BFD control packet , if not how to decided the INIT timeout time ? Before the session is UP if received a P bit set control packet , it will send back a F bit set control packet , but the vlaue of MTI and MRI in the control packet is setted to 1s or the actual value ?? 2、In Section 4.1 it said "Poll (P) If set, the transmitting system is requesting verification of connectivity, or of a parameter change. If clear, the transmitting system is not requesting verification." In Section 6.7.3 it said "If Demand mode is active, and either bfd.DesiredMinTxInterval is changed or bfd.RequiredMinRxInterval is changed, a Poll Sequence MUST be initiated (see section 6.7.8). If Demand mode is not active, bfd.SessionState is Up, and either bfd.DesiredMinTxInterval is changed or bfd.RequiredMinRxInterval is changed, all subsequent transmitted Control packets MUST be sent with the Poll (P) bit set until a packet is received with the Final (F) bit set (except for those packets sent in response to received Polls.)" In Section 6.7.13 it said "When it is desired to change the detect multiplier, the value of bfd.DetectMult can be changed to any nonzero value. The new value will be transmitted with the next BFD Control packet. See section 6.7.8 for additional requirements." I am not sure whether the "parameter change" said in Section 4.1 include the Detect Multiplier Change that said in Section 6.7.13 , or ONLY include the timer parameters that said in Section 6.7.3. pls list the "parameter change" case that said in Section 4.1 ! 3、In Section 6.7.3 , it only said that when MTI increased or MRI reduced the actual transmission interval or detection time MUST not change until a Control packet is received with the Final (F) bit set . if MTI reduced it will change the transmission interval immediately , but i think it will have problem until received a control packet from remote system if the changed MTI vlaue is very low but the remote MRI is very large . 4、a question for example : A ------ B MTI=100ms MTI=10ms MRI=20ms MRI=30ms MERI=20ms if A want to send echo packet , the actual echo transmission interval will be the largest value of A's MTI and A's MRI and B's MTI and B's MRI and B's MERI , is it right??? 5、if echo function is active , i am not sure whether the echo packet is sent periodly in Demand mode mode and Asynchronous mode , or ONLY sent periodly in Asynchronous mode and when needed in Demand mode?? 6、if echo function is active , the control packet is sent at least 1s and the control packet will take the 1s value in it , is it correct?? 7、if BFD run on the multi-hop route , it will only detect whether the route can reached the destination or not , it can not detect whether the route had changed on another route , is it correct ?? 8、BTW , in Section 6.7.8 it said "Note that if the I Hear You (H) bit is changing to zero, the session is going down and Demand mode will no longer be active." the statement is not right because the I Hear You (H) bit is removed. Thanks for your help!! Roggie