An IP Gateway is needed to provide the communications between your computer and the World Wide Web. A Network Switch can send the data, or packets, to the intended computer because of the capabilities of an IP Gateway Router.
What is a Sea Flea? There is much confusion about what people mean when they refer to a sea flea. While there is a marine creature of the Leptostraca family found in the waters around Australia that is called a sea flea, more often the term is actually used to describe the jellyfish larvae that can make sea bathers break out is a rash.
For example, this crustacean (although it resembles an insect, the sand flea is actually not one) is also called a sand fly, beach flea, hop-a-long, no-see-um, biting midge, and punkie or punky. The sand flea is less than 1/8 of an inch (3 mm) long and is often difficult to see.