where is class E ip addresses?

Question

I am reading Richard Stevens' TCP/IP illustrated Vol1.He said class E ip addresses are reserved for future use.Considering he wrote the book at 1994,now is the future.So where is the class E ip addresses?

I tried to ping 240.0.0.3 but windows returns

Destination specified is invalid

thanks.

Answer 1

IP Address Class E and Limited Broadcast The IPv4 networking standard defines Class E addresses as reserved, meaning that they should not be used on IP networks. Some research organizations use Class E addresses for experimental purposes. However, nodes that try to use these addresses on the Internet will be unable to communicate properly.