DNS over CoAP

<div class="n-demo"><div class="n-head"><strong>DNS MESSAGE IN COAP</strong><span>LIVE TRACE</span></div><div class="n-stage"><div class="doc"><div class="doc-device n-box">DEVICE<br><small>name?</small></div><div class="doc-wire"><div id="doc-packet" class="n-box"><small>CoAP FETCH</small><br>DNS query</div><div id="doc-arrow">→</div></div><div class="doc-device n-box">RESOLVER<br><small>address</small></div></div></div><div class="n-foot">tap to step · auto replay</div></div>

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let step=0;function advance(){document.getElementById('doc-packet').innerHTML=step<2?'<small>CoAP FETCH</small><br>DNS query':'<small>CoAP response</small><br>DNS answer';document.getElementById('doc-arrow').textContent=step<2?'→':'←';document.getElementById('doc-packet').classList.toggle('n-on',step===1||step===3);step=(step+1)%4}
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