フリー問題

問題文

A new link has just come up between two routers and no OSPF relationship exists on it yet. One router starts emitting packets at a fixed interval so that any OSPF speaker on that link learns of its presence and its parameters. Which packet type is being sent?

選択肢

1. Those periodic packets are acknowledgment messages on that newly connected link.
2. Those periodic packets are database description messages on that newly connected link.
3. Those periodic packets are hello messages on that newly connected link.
4. Those periodic packets are link state request messages on that newly connected link.