1. Packet Service Packet Extraction VC Access Service VC_FSH Service VC Frame Service MC_Insert Service MC Frame Service MC_OCF Service Virtual Channel Reception VC_OCF Service Virtual Channel Demultiplexing Master Channel Reception Master Channel Demultiplexing All Frames Reception Figure 2-6: Internal Organization of Protocol Entity (Receiving End) Figure 4-14: Internal Organization of Protocol Entity (Receiving End)

2. Packet Service Packet Processing VC Access Service VC_FSH Service VC Frame Service MC Frame Service MC_OCF Service Virtual Channel Generation VC_OCF Service Virtual Channel Multiplexing Master Channel Generation Master Channel Multiplexing All Frames Generation Figure 2-5: Internal Organization of Protocol Entity (Sending End) Figure 4-7: Internal Organization of Protocol Entity (Sending End) MC_Insert Service

3. Packet Service Packet VC Access Service VC_FSH Service VC Frame Service MC Frame Service MC_OCF Service VC_OCF Service Figure 2-7: AOS/TM Space Data Link Protocol Channel Tree VCA_SDUFSHVC_OCF VC Frame VCID Insert MC_OCF MC Frame MCID MC_Insert Service Commutator/ Decommutator Multiplexer/ DeMultiplexer Key

4. Figure 4-1: AOS Transfer Frame Structual Components Transfer Frame Primary Header Master Channel Insert Zone ( Optional ) Transfer Frame Secondary Header ( Optional ) Transfer Frame Data Field Transfer Frame Trailer ( Optional ) Operational Control Field ( Optional ) Frame Error Control Field ( Optional ) 6 OctetsUp to 64 OctetsVaries to fill framr4 Octets2 Octets Transfer Frame Primary Header Master Channel Insert Zone ( Optional ) Transfer Frame Secondary Header ( Optional ) Transfer Frame Data Field Transfer Frame Trailer ( Optional ) Operational Control Field ( Optional ) Frame Error Control Field ( Optional ) 6 OctetsFixedUp to 64 OctetsVaries to Fill Frame4 Octets2 Octets Figure 4-1: TM Transfer Frame Structual Components Fixed Transfer Frame Header Error Control ( optional ) 2 Octets

5. Figure 4-2: TM Transfer Frame Primary Header Transfer Frame Version Number Spacecraft ID Virtual Channel ID OCF Flag Master Channel ID Transfer Frame Data Field Status Master Channel Frame Count Virtual Channel Frame Count 2 Octets 2 bits10 bits3 bits 1 bits 1 Octets 2 Octets

6. Figure 4-2: AOS Transfer Frame Primary Header Transfer Frame Version Number Spacecraft ID Virtual Channel ID Signaling Flags Master Channel ID Frame Header Error Control (Optional) Virtual Channel Frame Count 2 Octets 2 bits10 bits1 bit 1 Octet3 Octets2 Octets Replay Flag VC Sec Hdr Flag VC Frame Count Usage Flag Spare VC Frame Count Cycle 6 bits1 bit 4 bits