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Ping

The purpose of this message is to check if the remote node is online.  It is used for maintaining the node table.


The ping query is sent as a plain BEncoded map, in a single UDP packet.  It has the following keys:

y
Set the value of this key to the string q because this is a query.

q
Set the value of this to the string ping to indicate this is a ping.

t
Set the value of this to a random 4-byte transaction ID.

a
This value is an inner map that represents the query arguments.  It contains the following keys:



The ping response is also a plain BEncoded map, in a single UDP packet.  It has the following keys:

y
Set the value of this key to the string r because this is a response.

t
Set the value of this to the transaction ID from the original query that we are responding to.

r
This value is an inner map that represents the response to the query.  It contains the following keys: