How does Australia guard its borders? Surrounded by the sea, the coastline is so long.

Hehe, I know what the landlord means. You mean Australia has a long coastline and there are not enough people to prevent smuggling. In fact, this should be from a realistic perspective. Australia has a long coastline, but Australia is an isolated continent, surrounded by the sea, which is far from other continents and islands. In other words, if you want to sneak into Australia by water, you need to take an ocean-going ship or a medium-sized ship. It would be "impossible to prevent" to land in the vast unguarded area on the west coast of Australia by boat, but which boat can cross the ocean? Indonesia, East Timor and Papua New Guinea are close to the north of Australia, but they actually need some distance. Australia has many navies and air forces there. Although it is not guaranteed to be tight, it will not allow a medium-sized or large ship to come in without permission. As long as legitimate ships land at designated ports, these ports will have special inspections to check the documents of passengers who land. stowaways usually come in by hitting this checkpoint. It goes without saying that there are many defenses near several coastal cities. For example, some people want to go ashore from no man's land or sparsely populated places on the west coast of Australia, which requires miniaturization of ships. The coast guard patrols the sea far from the coast, not the coast. With the help of advanced equipment, the observation range is very large. Even if a small boat escapes the guards and lands on a no-man's land or sparsely populated coast, it will face difficulties in land transportation and shortage of drinking water, which is similar to desert exploration. This kind of smuggling is really not easy, so the number of people smuggling in the past is far less than that from Mexico to the United States (land border)