| Ａ． | Ｂ． | Ｃ． | Ｄ． | |
| 7 | Physical | Application | Application | Application |
| 6 | Data-Link | Session | Presentation | Presentation |
| 5 | Session | Presentation | Session | Session |
| 4 | Transport | Transport | Network | Transport |
| 3 | Network | Network | Transport | Network |
| 2 | Presentation | Data-Link | Data-Link | Data-Link |
| 1 | Application | Physical | Physical | Physical |