static byte[] createNetworkNonce(final byte ctlTTL, @NonNull final byte[] sequenceNumber, final int src, @NonNull final byte[] ivIndex) {
        final ByteBuffer networkNonce = ByteBuffer.allocate(13);
        networkNonce.put((byte) NONCE_TYPE_NETWORK); //Nonce type
        networkNonce.put(ctlTTL); // CTL and TTL
        networkNonce.put(sequenceNumber);
        networkNonce.putShort((short) src);
        networkNonce.put(new byte[]{PAD_NETWORK_NONCE, PAD_NETWORK_NONCE}); //PAD
        networkNonce.put(ivIndex);
        return networkNonce.array();
    }
Creates the network nonce

@param ctlTTL         Combined ctl and ttl value
@param sequenceNumber Sequence number of the message
@param src            Source address
@return Network nonce
mesh/src/main/java/no/nordicsemi/android/mesh/transport/NetworkLayer.java