The final test

E1 What kind of document is TS 23.501?

• A list of the service requirements a 5G network has to meet
• The architecture of the 5G system: which functions exist and what each one owns
• The exact messages a phone and a network exchange

E2 How may two control-plane functions of the 5G core talk to each other?

• Only over a dedicated link between the two
• Over whichever the operator has cabled up
• Only over service-based interfaces

E3 Which network function is the only one that forwards a user's packets?

• The AMF
• The SMF
• The UPF

E4 A device is registered but has sent nothing for hours. What does the core still have?

• Nothing — the record was dropped when the device went quiet
• An open tunnel waiting for its next packet
• A record of the device, and the ability to page it

E5 What does a device need before it can send a packet to a data network?

• A PDU session
• A network slice of its own
• A QoS Flow

E6 Which of the three stages does TS 23.501 belong to?

• Stage 1, the requirements
• Stage 2, the architecture
• Stage 3, the messages on the wire

E7 The document says "some or all of the UPF functionalities may be supported in a single instance of a UPF". What does that tell you about a network function?

• It is a named list of jobs, and a real network may run many instances of it
• It is a product a vendor sells under that name
• It is one server, running one program

E8 A registered phone lies on a bedside table all night, sending nothing. Which pair of states is it in?

• Registered and connected
• Deregistered and idle
• Registered and idle

E9 What is the finest thing a 5G network can give a separate quality treatment to?

• A whole session
• A QoS Flow
• A single packet

E10 Which two documents does the scope name as the companions of this one?

• TS 24.501 and TS 29.500
• TS 38.300 and TS 38.401
• TS 23.502 and TS 23.503