[P2PSIP] RFC6940: Detecting Partitioning

Evgeny <xramtsov@gmail.com> Sun, 14 October 2018 19:04 UTC

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Date: Sun, 14 Oct 2018 22:04:38 +0300
From: Evgeny <xramtsov@gmail.com>
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Subject: [P2PSIP] RFC6940: Detecting Partitioning
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Hi there

I have hard time understanding the mechanism described in 10.7.4.4 
(Detecting Partitioning) [1]:

 > P SHOULD then send a Ping for its own Node-ID routed through B.
 > If a response is received from peer S', which is not P's successor,
 > then the overlay is partitioned

How is it even possible? Given the Symmetric Recursive Routing, the 
Ping answer will always come from node B.
I tried to grasp through the RFC about special routing rules of Ping 
answers, but I didn't find anything special
except the statement in 6.1.2 (Other ID) [2] which I *fail* to 
understand:

 > The node MUST implement support for
 > returning responses to a Ping or Attach request made by a Joining
 > Node Attaching to its responsible peer

"made by a Joining Node Attaching to its responsible peer"? What does 
that mean exactly? Why is "Attaching"
with a capital letter?

[1] https://tools.ietf.org/html/rfc6940#section-10.7.4.4
[2] https://tools.ietf.org/html/rfc6940#section-6.1.2