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Bug #3335

closed

ping: does not process Nack

Added by Junxiao Shi about 9 years ago. Updated over 8 years ago.

Status:
Closed
Priority:
Normal
Assignee:
Start date:
11/12/2015
Due date:
% Done:

100%

Estimated time:
2.00 h

Description

ndn::ping::client::Ping::performPing is using a deprecated overload of Face::expressInterest that does not process Nack.

To fix this bug, Nack processing should be added.


Related issues 2 (0 open2 closed)

Related to NFD - Bug #3694: integ fails due to ndnpeek/ndnping syntax changeClosedEric Newberry08/01/2016

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Blocks ndn-cxx - Task #3334: Deprecate Face::expressInterest non-Nack overloadsClosedZhiyi Zhang

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Actions #1

Updated by Junxiao Shi about 9 years ago

  • Blocks Task #3334: Deprecate Face::expressInterest non-Nack overloads added
Actions #2

Updated by Junxiao Shi almost 9 years ago

  • Tracker changed from Task to Bug
  • Description updated (diff)
Actions #3

Updated by Teng Liang over 8 years ago

  • Assignee set to Teng Liang
Actions #4

Updated by Teng Liang over 8 years ago

On receiving NACK, what messages are expected to be printed out? Sequence number and NACK reason?

Actions #5

Updated by Junxiao Shi over 8 years ago

Answer to note-4:

Currently, Data and timeout prints:

content from /ndn/edu/arizona: seq=4968989894049509434 time=137.026 ms
timeout from /ndn/edu/arizona: seq=4797694481388730425

I think Nack can print in a similar format:

nack from /ndn/edu/arizona: seq=10327383310863275811 time=112.471 ms reason=Congestion
Actions #6

Updated by Junxiao Shi over 8 years ago

A related question is:
How Nack should be reflected in the statistics?

So far, the statistics is following the format of IP ping, but there's no Nack in IP ping that we can learn from.

I don't have a good answer for this.

Actions #7

Updated by Teng Liang over 8 years ago

Junxiao Shi wrote:

A related question is:
How Nack should be reflected in the statistics?

So far, the statistics is following the format of IP ping, but there's no Nack in IP ping that we can learn from.

I don't have a good answer for this.

As Nack is not the expected packet and can be generated by any router along the path, it should be considered as a packet loss.

Actions #8

Updated by Junxiao Shi over 8 years ago

I agree with note-7. This also implies that the RTT of Nacks should not be included in the overall RTT in the statistics.

Actions #9

Updated by Anonymous over 8 years ago

Maybe you can have a separate count for the nacks, like:

7 packets transmitted, 5 received, 2 nacked, x% packet loss, y% nacked,  time 12.5148 ms

Maybe you could also keep separate RTT estimates for NACKs to give the user some idea where the nacks come from:

rtt min/avg/max/mdev = 1.42586/2.50295/6.29782/1.89921 ms
nack min/avg/max/mdev = 1.25688/3.69249/10.555/3.96418 ms
Actions #10

Updated by Junxiao Shi over 8 years ago

I agree with the first half of note-9: having counts for Nacks.

I disagree with the second half of note-9.

Nack is only on a single hop.
A forwarder may receive a Nack and transmit another Nack, but never forward a Nack.
Thus, the origin of any Nack received by application is the directly connected forwarder.

Actions #11

Updated by Teng Liang over 8 years ago

  • Status changed from New to Code review
Actions #12

Updated by Davide Pesavento over 8 years ago

I agree with Junxiao.

Actions #13

Updated by Anonymous over 8 years ago

Junxiao Shi wrote:
I agree with the first half of note-9: having counts for Nacks.

I disagree with the second half of note-9.

Nack is only on a single hop.
A forwarder may receive a Nack and transmit another Nack, but never forward a Nack.
Thus, the origin of any Nack received by application is the directly connected forwarder.

Agreed, makes sense!

Actions #14

Updated by Junxiao Shi over 8 years ago

  • Status changed from Code review to Closed
  • % Done changed from 0 to 100
Actions #15

Updated by Junxiao Shi over 8 years ago

  • Related to Bug #3694: integ fails due to ndnpeek/ndnping syntax change added
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