OkHttp perseveres when the network is troublesome: it will silently recover from common connection
problems. If your service has multiple IP addresses, OkHttp will attempt alternate addresses if the
first connect fails. This is necessary for IPv4+IPv6 and services hosted in redundant data
centers. OkHttp supports modern TLS features (TLS 1.3, ALPN, certificate pinning). It can be
configured to fall back for broad connectivity.

        
        if (rssCapable) score += 1000;   // Prefer RSS-capable
        if (rdmaCapable) score += 2000;  // Prefer RDMA-capable
        if (!ipv6) score += 100;         // Slight preference for IPv4
        
        return score;
    }
    
    private boolean checkRSSCapability() {
        // Platform-specific RSS detection
        // Simplified implementation
        try {

http://%zz%66%a.com

# If we get an invalid character that has been escaped.
http://%25
http://hello%00

# Escaped numbers should be treated like IP addresses if they are.
# No special handling for IPv4 or IPv4-like URLs
http://%30%78%63%30%2e%30%32%35%30.01  s:http p:/ h:192.168.0.1
http://%30%78%63%30%2e%30%32%35%30.01%2e  s:http p:/ h:0xc0.0250.01.
http://192.168.0.257

		"",
	)

	ErrInvalidAddressFlag = newErrFn(
		"--address input is invalid",
		"Please check --address parameter",
		`--address binds to a specific ADDRESS:PORT, ADDRESS can be an IPv4/IPv6 address or hostname (default port is ':9000')
	Examples: --address ':443'
		  --address '172.16.34.31:9000'
		  --address '[fe80::da00:a6c8:e3ae:ddd7]:9000'`,
	)

	ErrInvalidEndpoint = newErrFn(

- `-- kube-controller-manager`
  `--node-cidr-mask-size-ipv4 int32`     Default: 24. Mask size for IPv4 node-cidr in dual-stack cluster.
`--node-cidr-mask-size-ipv6 int32`     Default: 64. Mask size for IPv6 node-cidr in dual-stack cluster.

 * authentication.
 *
 * ### Host
 *
 * The host identifies the webserver that serves the URL's resource. It is either a hostname like
 * `square.com` or `localhost`, an IPv4 address like `192.168.0.1`, or an IPv6 address like `::1`.
 *
 * Usually a webserver is reachable with multiple identifiers: its IP addresses, registered

- File content check for IPV4 is now enabled by default, and the check of IPV4 or IPV6 is done for `kubeadm init` or `kubeadm join` only in case the user intends to create a cluster to support that kind of IP address family ([#115420](https://github.com/kubernetes/kubernetes/pull/115420), [@chendave](...

     * parts other than the last may begin with a digit (for example, "3com.com"). It's important to
     * disallow an initial digit in the last part; it's the only thing that stops an IPv4 numeric
     * address like 127.0.0.1 from looking like a valid domain name.
     */

    if (isFinalPart && DIGIT_MATCHER.matches(part.charAt(0))) {
      return false;
    }

    return true;
  }

* 'kubectl describe pv' now shows events ([#27431](https://github.com/kubernetes/kubernetes/pull/27431), [@jsafrane](https://github.com/jsafrane))
* AWS kube-up: set net.ipv4.neigh.default.gc_thresh1=0 to avoid ARP over-caching ([#27682](https://github.com/kubernetes/kubernetes/pull/27682), [@justinsb](https://github.com/justinsb))

    val session = handshakeCertificates.sslContext().createSSLEngine().session
    assertThat(localVerifier.verify("\uD83D\uDCA9.com", session)).isFalse()
  }

  @Test fun verifyAsIpAddress() {
    // IPv4
    assertThat("127.0.0.1".canParseAsIpAddress()).isTrue()
    assertThat("1.2.3.4".canParseAsIpAddress()).isTrue()

    // IPv6
    assertThat("::1".canParseAsIpAddress()).isTrue()