Project

General

Profile

Task #3627

Use /localhop component in Sync prefix to reduce duplicate NACKs

Added by Vince Lehman about 3 years ago. Updated over 2 years ago.

Status:
Closed
Priority:
Normal
Target version:
Start date:
05/25/2016
Due date:
% Done:

100%

Estimated time:

Description

Currently, Sync Interests are multicasted at each router which can result in Interests traversing a loop; these loops cause NFD to send a Duplicate NACK in response.

If instead the Sync prefix was prefixed with the /localhop component, the Interests would only be multicasted and delivered to immediate neighbors.

History

#1 Updated by Junxiao Shi almost 3 years ago

Using /localhop cannot reduce Nack-Duplicates in the case of ChronoSync Interests.

ScopeControl restricts /localhop Interest forwarding as follows:

  • If PIT entry has at least one InRecord from a local face, it can be forwarded to local faces and non-local faces.
  • If PIT entry has all InRecords from non-local faces, it can only be forwarded to local faces.

As soon as the local NLSR has expressed a sync Interest, NFD can forward a sync Interest received from one remote router to another remote router, and cause the same amount of Nack-Duplicates.

#2 Updated by Lan Wang almost 3 years ago

What's the rationale for this rule "If PIT entry has at least one InRecord from a local face, it can be forwarded to local faces and non-local faces."?

#3 Updated by Junxiao Shi almost 3 years ago

Answer to note-2:

The alternate is: "If PIT entry does not have any InRecord from a non-local face, it can be forwarded to non-local faces".

This breaks the scenario when two nodes try to send the same Interest to each other.

#4 Updated by Lan Wang almost 3 years ago

In what case will two nodes try to send the same Interest to each other using /localhop and why would you like to forward the interest to other nodes in this case?

#5 Updated by Ashlesh Gawande over 2 years ago

  • Assignee set to Ashlesh Gawande

#6 Updated by Ashlesh Gawande over 2 years ago

Rules have changed: https://redmine.named-data.net/issues/3836

I have tested this on a 34 node topology, no Duplicate NACKs are generated by sync interests (this reduced Duplicate NACKs from ~47000 to ~15000, those generated are by LSA interests).

#7 Updated by Ashlesh Gawande over 2 years ago

  • Status changed from New to Closed
  • % Done changed from 0 to 100

#8 Updated by Nicholas Gordon over 2 years ago

  • Target version set to v0.3.1

#9 Updated by Ashlesh Gawande over 2 years ago

  • Status changed from Closed to Feedback

advertise and withdraw does not work when security is turned on after this patch.

Validation of received interest fails:
Name prefix update error (code: 403)

Not sure if it is because of this patch.

My bad, the interest needs to be signed when security is enabled. It is working as expected.

#10 Updated by Ashlesh Gawande over 2 years ago

  • Status changed from Feedback to Closed

Also available in: Atom PDF