Networking Explained, 2nd Edition

Chapter 9

Token Ring

In this chapter we present an overview of token ring networks, IEEE 802.5. Unlike Ether-

net/802.3 LANs in which nodes contend for media access, token ring LANs use a token-

passing scheme; that is, media access in token ring LANs is controlled by the possession

of a token. We discussed general issues relating to token passing, including a comparison

of random access and token passing protocols, in Chapter 5, which you might want to

review before proceeding. In addition to token ring, the IEEE standards include a second

token passing protocol called token bus. Although token bus use is uncommon, we present

a brief comparison of the two token passing schemes for completeness. An outline of the

major topics we present in this chapter ...