The problem with multilevel IVRs is that the caller has to enter single digits multiple times (oftentimes the same digit), but gets a different response depending on the menu level. Because a number can only be used once in a given context, the caller would be stuck on the first menu level. If we need multiple menus which provide different responses for the same digits, we must place the submenus in different contexts ([cafeteria] in our example). We jump between these contexts using the application Goto() (see the section called “Goto()”). Let's assume you have the following sound files stored in /var/lib/asterisk/sounds/:

If sales is at extension 100 and the service department is at 150, the dialplan for this IVR would look like this:

[example-ivr]
; The menu is repeated until the caller provides input.
;
exten => 30,1,Answer()
exten => 30,2,Background(mainmenu)
exten => 30,3,Background(silence/3)
exten => 30,4,Goto(2)

exten => 1,1,Dial(SIP/100)

exten => 2,1,Dial(SIP/150)

; Goto() jumps to another context ([cafeteria])
;
exten => 3,1,Goto(cafeteria,100,1)

exten => i,1,Goto(30,2)

[cafeteria]
exten => 100,1,Background(cafeteria)
exten => 100,2,Background(silence/3)
exten => 100,3,Goto(1)

exten => 1,1,Playback(cafeteria-menu-this-week)
exten => 1,2,Wait(2)
exten => 1,3,Goto(1)

exten => 2,1,Playback(cafeteria-menu-next-week)
exten => 2,2,Wait(2)
exten => 2,3,Goto(1)

; Invalid input sends the caller back to the main menu
exten => i,1,Goto(example-ivr,30,2)