This illustration of a WEB protocol appears in five layers. The top layer is a white rectangle labeled "Key sequence generator (for given Ks, IV)." Below this we see Ks: 40-bit secret symmetric, which appears as this series: K1 IV, K2 IV, K3 IV ... Kn IV, Kn+1 IV ... Kn+4 IV.

Below each of these is a circle labeled "+." Vertical lines above and below connect the circle with the data above and below it. Below the circles, we see "Plaintext frame data plus CRC," which appears as this series: d1, d2, d3 ... dN, CRC1 ... CRC4. Dashed arrows point vertically down from each of these to the data below it, which appears as this series: c1, c2, c3 ... cN, cN+1 ... cN+4.

To the right of this figure is a section of datagram, which includes three segments: 802.11 header, IV, and WEP-encrypted data plus CRC. A blue arrow points from the bottom layer of the protocol to the WEP-encrypted data plus CRC segment of the datagram, and a blue arrow points from a label to the left of the figure, "IV (per frame)," to the Key Sequence Generator" and to the IV segment of the datagram.