4.5.18 Keypad facility The purpose of the Keypad facility information element is to convey IA5 characters, e.g. entered by means of a terminal keypad. The Keypad facility information element is coded as shown in Figure 4-24. The maximum length of this information element is 34 octets. 8 7 6 5 4 3 2 1 Octets Keypad facility 0 0 1 0 1 1 0 0 1 Information element identifier Length of the keypad facility contents 2 0 Keypad facility information (IA5 characters) 3 etc. FIGURE 4-24/Q.931 Keypad facility information element