new SipHashFunction(2, 4, 0x0706050403020100L, 0x0f0e0d0c0b0a0908L);

  // The number of compression rounds.
  private final int c;
  // The number of finalization rounds.
  private final int d;
  // Two 64-bit keys (represent a single 128-bit key).
  private final long k0;
  private final long k1;

  /**
   * @param c the number of compression rounds (must be positive)
   * @param d the number of finalization rounds (must be positive)

   * addresses, the output follows <a href="http://tools.ietf.org/html/rfc5952">RFC 5952</a> section
   * 4. The main difference is that this method uses "::" for zero compression, while Java's version
   * uses the uncompressed form.
   *
   * <p>This method uses hexadecimal for all IPv6 addresses, including IPv4-mapped IPv6 addresses