問題文
A core spreads a flow over several equal paths using a label that carries nothing but a value for that purpose, and each router advertises a depth that relates to such a label. An engineer has to record what that advertised depth counts, and what a router that can read the labels but cannot use one of them has to advertise. Which statement is correct?
選択肢
- It counts the labels the router can both read from the top of the stack and use in spreading the load, and such a router has to advertise the number it can read.
- It counts the labels the router can read from the top of the stack whatever it does with them, and such a router has to advertise zero.
- It counts the labels the router can both read from the top of the stack and use in spreading the load, and such a router has to advertise zero.
- It counts the labels the router can read from the top of the stack whatever it does with them, and such a router has to advertise the number it can read.