}

  /** Returns a new bias. */
  private fun adapt(
    delta: Int,
    numpoints: Int,
    first: Boolean,
  ): Int {
    var delta =
      when {
        first -> delta / DAMP
        else -> delta / 2
      }
    delta += (delta / numpoints)
    var k = 0
    while (delta > ((BASE - TMIN) * TMAX) / 2) {
      delta /= (BASE - TMIN)
      k += BASE
    }

      }

      val expires = this.expires
      if (expires != null) {
        val servedMillis = servedDate?.time ?: receivedResponseMillis
        val delta = expires.time - servedMillis
        return if (delta > 0L) delta else 0L
      }

      if (lastModified != null && cacheResponse.request.url.query == null) {
        // As recommended by the HTTP RFC and implemented in Firefox, the max age of a document

    }
  }

  companion object {
    internal const val EMIT_BUFFER_SIZE = 16384L
  }

  /** [delta] will be negative if a settings frame initial window is smaller than the last. */
  fun addBytesToWriteWindow(delta: Long) {
    writeBytesMaximum += delta
    if (delta > 0L) {
      condition.signalAll()
    }
  }

  @Throws(IOException::class)
  internal fun checkOutNotClosed() {

      in 64..79 -> {
        // Mapped inline as codePoint delta to subtract
        val b2 = ranges[rangesIndex + 2].code
        val b3 = ranges[rangesIndex + 3].code

        val codepointDelta = (b1 and 0xF shl 14) or (b2 shl 7) or b3
        sink.writeUtf8CodePoint(codePoint - codepointDelta)
      }
      in 80..95 -> {
        // Mapped inline as codePoint delta to add
        val b2 = ranges[rangesIndex + 2].code

      ) {
        var index = index
        headerList.add(entry)

        var delta = entry.hpackSize
        if (index != -1) { // Index -1 == new header.
          delta -= dynamicTable[dynamicTableIndex(index)]!!.hpackSize
        }

        // if the new or replacement header is too big, drop all entries.
        if (delta > maxDynamicTableByteCount) {
          clearDynamicTable()
          return
        }

    sink.close()
  }

  /**
   * @param delta the offset from the current date to use. Negative values yield dates in the past;
   * positive values yield dates in the future.
   */
  private fun formatDate(
    delta: Long,
    timeUnit: TimeUnit,
  ): String {
    return formatDate(Date(System.currentTimeMillis() + timeUnit.toMillis(delta)))
  }

  private fun formatDate(date: Date): String {

  }

  /**
   * @param delta the offset from the current date to use. Negative values yield dates in the past;
   *     positive values yield dates in the future.
   */
  private fun formatDate(
    delta: Long,
    timeUnit: TimeUnit,
  ): String? {
    return formatDate(Date(System.currentTimeMillis() + timeUnit.toMillis(delta)))
  }

  private fun formatDate(date: Date): String? {

              }
            }

          val peerInitialWindowSize = newPeerSettings.initialWindowSize.toLong()
          delta = peerInitialWindowSize - previousPeerSettings.initialWindowSize.toLong()
          streamsToNotify =
            when {
              delta == 0L || streams.isEmpty() -> null // No adjustment is necessary.
              else -> streams.values.toTypedArray()
            }

Istio currently supports both SotW and Delta protocol. However, the delta implementation is not yet optimized well, so it performs mostly the same as SotW.

## Controllers

  // expirationSeconds is the requested duration of validity of the issued
  // certificate. The certificate signer may issue a certificate with a different
  // validity duration so a client must check the delta between the notBefore and
  // and notAfter fields in the issued certificate to determine the actual duration.
  //
  // The v1.22+ in-tree implementations of the well-known Kubernetes signers will