* Don't start a new attempt until 250 ms after the most recent attempt was started.
 * Keep whichever TCP connection succeeds first and cancel all the others.
 * Race TCP only. Only attempt a TLS handshake on the winning TCP connection.

import java.util.List;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import jcifs.Configuration;
import jcifs.internal.smb2.rdma.disni.DisniRdmaProvider;
import jcifs.internal.smb2.rdma.tcp.TcpRdmaProvider;

/**
 * Factory for creating RDMA provider instances.
 *
 * This factory attempts to select the best available RDMA provider
 * based on system capabilities and configuration preferences.
 */

After this, the client and the server have an **encrypted TCP connection**, this is what TLS provides. And then they can use that connection to start the actual **HTTP communication**.

And that's what **HTTPS** is, it's just plain **HTTP** inside a **secure TLS connection** instead of a pure (unencrypted) TCP connection.

/// tip

            throw new IOException("TCP RDMA receive failed", e);
        }
    }

    @Override
    public void rdmaRead(RdmaMemoryRegion localRegion, long remoteAddress, int remoteKey, int length) throws IOException {
        // TCP fallback doesn't support real RDMA read
        throw new UnsupportedOperationException("RDMA read not supported by TCP fallback");
    }

    @Override

Após isso, o cliente e o servidor possuem uma **conexão TCP encriptada**, que é provida pelo TLS. E então eles podem usar essa conexão para começar a **comunicação HTTP** propriamente dita.

E isso resume o que é **HTTPS**, apenas **HTTP** simples dentro de uma **conexão TLS segura** em vez de uma conexão TCP pura (não encriptada).

/// tip | Dica

        props.setProperty("jcifs.smb.client.useRDMA", "true");
        props.setProperty("jcifs.smb.client.rdmaProvider", "tcp");

        PropertyConfiguration config = new PropertyConfiguration(props);

        assertTrue(config.isUseRDMA(), "RDMA should be enabled");
        assertEquals("tcp", config.getRdmaProvider(), "Provider should be tcp");
    }

    @Test
    public void testRdmaAutoProvider() throws CIFSException {

import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.mockito.Mock;
import org.mockito.MockitoAnnotations;

import jcifs.internal.smb2.rdma.tcp.TcpMemoryRegion;

/**
 * Unit tests for RDMA buffer manager
 */
public class RdmaBufferManagerTest {

    @Mock
    private RdmaProvider mockProvider;

    private RdmaBufferManager bufferManager;

import okhttp3.internal.platform.Platform
import okhttp3.internal.tls.OkHostnameVerifier
import okhttp3.internal.toHostHeader

/**
 * A single attempt to connect to a remote server, including these steps:
 *
 *  * [TCP handshake][connectSocket]
 *  * Optional [CONNECT tunnels][connectTunnel]. When using an HTTP proxy to reach an HTTPS server
 *    we must send a `CONNECT` request, and handle authorization challenges from the proxy.

次に証明書を使用して、クライアントとTLS Termination Proxy は、 **TCP通信**の残りを**どのように暗号化するかを決定**します。これで**TLSハンドシェイク**の部分が完了します。

この後、クライアントとサーバーは**暗号化されたTCP接続**を持ちます。そして、その接続を使って実際の**HTTP通信**を開始することができます。

これが**HTTPS**であり、純粋な（暗号化されていない）TCP接続ではなく、**セキュアなTLS接続**の中に**HTTP**があるだけです。

/// tip

通信の暗号化は、HTTPレベルではなく、**TCPレベル**で行われることに注意してください。

///

### HTTPS リクエスト

import java.util.EnumSet;
import java.util.Set;

/**
 * Interface for RDMA provider implementations.
 *
 * This interface abstracts different RDMA implementations such as
 * InfiniBand, iWARP, RoCE, or TCP fallback providers.
 */
public interface RdmaProvider {

    /**
     * Check if RDMA is available on this system
     *
     * @return true if RDMA can be used, false otherwise
     */