Subject: RE: ZLB Ack question

From: Vipin Jain <[email-masked]>
Date: Mon, 23 Oct 2000 18:13:04 -0700

<<thans for responding, more comments in>>

-----Original Message-----
From: [email-masked] [mailto:[email-masked]]
Sent: Monday, October 23, 2000 6:07 PM
To: Vipin Jain
Cc: [email-masked]
Subject: Re: ZLB Ack question

Vipin,
The LAC retransmitting the seq # 1 and acking seq # 33 are two independent
things.
It should retransmit seq #1 only when the retransmit timer for #1 fires.
<<agree>>

1 case :
Assume , for this case, that the timer has not yet fired when it gets seq
#33.
At this point, it may either ack #33 with a ZLB (assuming it has no data to
send, and Ns for the ZLB will be 5), or apply some sort of delayed ack
mechanism; i.e wait for some control packet to be sent and make its Nr as
34.
<< My question was about this case: Delayed ack timer expires before re-xmt
timer>>
<< remote is going to throw this because this is out of its receive window,
there by creating unwanted noise traffic, any way to avoid this unwanted and
useless traffic? >>

2 case:
Assume , now  the case where the retransmit timer for #1 fires just after it
gets #33. In that scenario, it could transmit the packet  with Ns=1 and Nr =
34.
<<agree>>

Madhvi

Vipin Jain <[email-masked]> on 10/23/2000 11:40:47 PM

Sent by:  Vipin Jain <[email-masked]>

To:   [email-masked]
cc:    (Madhvi Verma/MW/US/3Com)
Subject:  ZLB Ack question

LAC  ---- seq #1 --> *LOST*       LNS
LAC  ----- seq #2 --------------> LNS
LAC  ------ seq #3 -------------> LNS
LAC  ------ seq #4 -------------> LNS
LAC  <------ seq #33 ------------- LNS

Should LAC ZLB Ack LNS seq#33?
If so what should be Ns in ZLB Ack?
Or should LAC retransmit seq #1 to LNS acking seq#33?

**** LAC Actually times out on seq #1 here ***

Thanks for any insights.
-- vipin