Draw a sequence diagram for the scenario for a session with an online stock broker:

John Doe logs in

System establishes secure communications

System displays portfolio information

John Doe enters a buy order for 100 shares of GE at the market price

System verifies sufficient funds for purchase

System displays confirmation screen with estimated cost

John Doe confirms purchase

System places order on securities exchange

System displays transaction tracking number

John Doe logs out

System establishes insecure communications

System displays good-bye screen

System exchange reports results of trade