RG            UP              CP         AAA      Web Server
     | User traffic|                |          |           |
    1|------------>|                |          |           |
     |             | User traffic   |          |           |
     |            2|-----via Si---->|    AAA   |           |
     |             |                |  Req/Rep |           |
     |             |               3|<-------->|           |
     |             | Create Session |          |           |
     |             |    Request     |          |           |
     |            4|<----via Ci-----|          |           |
     |             | Create Session |          |           |
     |             |    Response    |          |           |
     |            5|----via Ci----->|          |           |
     |             |                |          |           |
     | HTTP traffic|                |          |           |
    6|------------>|                |          |           |
     |             |                |          |           |
     | Redirect to |                |          |           |
     |   Web URL   |                |          |           |
    7|<------------|                |          |           |
     |             |                |          |           |
     |                                                     |
    8|-----------------Redirected to Web Server----------->|
     |                                                     |
    9|<----------------Push HTTP Log-in Page---------------|
     |                                                     |
   10|-----------------User Authentication---------------->|
     |                                                     |
     |             |                |  Portal Interchange  |
     |             |              11|<-------------------->|
     |             |                |                      |
     |             |                |   AAA    |           |
     |             |                |  Req/Rep |           |
     |             |              12|<-------->|           |
     |             |                |          |           |
     |             | Update Session |          |           |
     |             |    Request     |          |           |
     |           13|<----via Ci-----|          |           |
     |             | Update Session |          |           |
     |             |    Response    |          |           |
     |           14|----via Ci----->|          |           |
     |             |                |          |           |