for (int i = 0; i < initialSendBuffers; i++) {
            try {
                ByteBuffer buffer = ByteBuffer.allocateDirect(sendBufferSize);
                RdmaMemoryRegion region = provider.registerMemory(buffer, EnumSet.of(RdmaAccess.LOCAL_READ, RdmaAccess.REMOTE_READ));
                availableSendRegions.offer(region);
                totalAllocated.incrementAndGet();
            } catch (IOException e) {

    @BeforeEach
    public void setUp() throws Exception {
        mocks = MockitoAnnotations.openMocks(this);

        // Set up mock provider to return TCP memory regions
        when(mockProvider.registerMemory(any(ByteBuffer.class), any())).thenAnswer(invocation -> {
            ByteBuffer buffer = invocation.getArgument(0);
            EnumSet<RdmaAccess> access = invocation.getArgument(1);

                                   InetSocketAddress local) throws IOException;
    
    /**
     * Register memory region for RDMA operations
     */
    RdmaMemoryRegion registerMemory(ByteBuffer buffer, 
                                   EnumSet<RdmaAccess> access) throws IOException;
    
    /**
     * Get provider name (e.g., "InfiniBand", "iWARP", "RoCE")
     */
    String getProviderName();

        RdmaConnection connection = createConnection(remoteAddress, null);
        connection.connect();
        return connection;
    }

    @Override
    public RdmaMemoryRegion registerMemory(ByteBuffer buffer, EnumSet<RdmaAccess> access) throws IOException {
        // TCP doesn't need real memory registration
        return new TcpMemoryRegion(buffer, access);
    }

    @Override

        RdmaConnection connection = createConnection(remoteAddress, null);
        connection.connect();
        return connection;
    }

    @Override
    public RdmaMemoryRegion registerMemory(ByteBuffer buffer, EnumSet<RdmaAccess> access) throws IOException {
        ensureInitialized();
        return new DisniMemoryRegion(buffer, access, endpoint);
    }

    /**

     * @param access access permissions for the memory region
     * @return registered memory region
     * @throws IOException if memory registration fails
     */
    RdmaMemoryRegion registerMemory(ByteBuffer buffer, EnumSet<RdmaAccess> access) throws IOException;

    /**
     * Get provider name (e.g., "InfiniBand", "iWARP", "RoCE", "TCP Fallback")
     *
     * @return human-readable provider name
     */

        this.endpoint = endpoint;

        // In real implementation, this would register the memory:
        // try {
        //     int accessFlags = convertAccessFlags(access);
        //     memoryRegister = endpoint.registerMemory(buffer, accessFlags).execute().free();
        // } catch (Exception e) {
        //     throw new RuntimeException("Failed to register memory region", e);
        // }

        ByteBuffer buffer = ByteBuffer.allocateDirect(1024);
        EnumSet<RdmaAccess> access = EnumSet.of(RdmaAccess.LOCAL_READ, RdmaAccess.LOCAL_WRITE);

        RdmaMemoryRegion region = provider.registerMemory(buffer, access);
        assertNotNull(region, "Memory region should not be null");
        assertEquals(buffer, region.getBuffer(), "Buffer should match");