<p>Yes the second case (pinging two different nodes) is fixed by source address checking, but not the first case.</p>
<p>I don't actually know what is the intended use of <code>id</code> or whether it's supposed to be unique per node or unique per invocation. But if we make it unique per invocation then it helps solve the first case:</p>
<ul>
<li>invoke <code>ping6</code> to send a ping to any node</li>
<li>invoke <code>ping6</code> again to ping the same node</li>
<li>any delayed pongs from the first invocation will be counted by the second invocation. Maybe not everyone agrees that this is wrong behavior, but if we can prevent it I think we should.</li>
</ul>

<p style="font-size:small;-webkit-text-size-adjust:none;color:#666;">—<br />You are receiving this because you are subscribed to this thread.<br />Reply to this email directly, <a href="https://github.com/RIOT-OS/RIOT/issues/11519?email_source=notifications&email_token=ABE7WYG5UBWUCBP2RMG6WW3QCCRLJA5CNFSM4HMRAH6KYY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOD3FH3VY#issuecomment-516586967">view it on GitHub</a>, or <a href="https://github.com/notifications/unsubscribe-auth/ABE7WYHJHTVVBNKTOG4D2RDQCCRLJANCNFSM4HMRAH6A">mute the thread</a>.<img src="https://github.com/notifications/beacon/ABE7WYHEZNE72LCGL66G3ZLQCCRLJA5CNFSM4HMRAH6KYY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOD3FH3VY.gif" height="1" width="1" alt="" /></p>
<script type="application/ld+json">[
{
"@context": "http://schema.org",
"@type": "EmailMessage",
"potentialAction": {
"@type": "ViewAction",
"target": "https://github.com/RIOT-OS/RIOT/issues/11519?email_source=notifications\u0026email_token=ABE7WYG5UBWUCBP2RMG6WW3QCCRLJA5CNFSM4HMRAH6KYY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOD3FH3VY#issuecomment-516586967",
"url": "https://github.com/RIOT-OS/RIOT/issues/11519?email_source=notifications\u0026email_token=ABE7WYG5UBWUCBP2RMG6WW3QCCRLJA5CNFSM4HMRAH6KYY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOD3FH3VY#issuecomment-516586967",
"name": "View Issue"
},
"description": "View this Issue on GitHub",
"publisher": {
"@type": "Organization",
"name": "GitHub",
"url": "https://github.com"
}
}
]</script>