802.5 topology is called
802.5 topology is called token ring.
Token ring network specifies a star, with all end stations attached to a device called a multistation access unit (MSAU). Token ring (IEEE 802.5) was developed by IBM in the 1970s and is described in the IEEE802.5 specification. It is no longer widely used in LANs. Token passing is the method of medium access, with only one token allowed to exist on the network at any one time.
A token ring network is a local area network (LAN) in which all computers are connected in a ring or star topology and a bit- or token-passing scheme is used in order to prevent the collision of data between two computers that want to send messages at the same time.