Task #3627
closed
Use /localhop component in Sync prefix to reduce duplicate NACKs
100%
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.
Updated by Junxiao Shi over 7 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.
Updated by Lan Wang over 7 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."?
Updated by Junxiao Shi over 7 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.
Updated by Lan Wang over 7 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?
Updated by Ashlesh Gawande over 7 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).
Updated by Ashlesh Gawande over 7 years ago
- Status changed from New to Closed
- % Done changed from 0 to 100
Updated by
Updated by Ashlesh Gawande over 7 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.
Updated by Ashlesh Gawande over 7 years ago
- Status changed from Feedback to Closed