Introduction to Data Communications
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When the packet arrives at node G, node G reads the destination address and reads the information. Node G marks the information packet as read and passes it on.

Note: the Source and Destination addresses remain unchanged after passing through Node G. Node B is still the Source address and Node G is still the Destination address.

The packet continues around the ring, until it reaches the source address Node B. Node B checks to make sure that the packet has been read - this indicates that Node G is actually present. The information packet is erased. Node B then releases the token onto the ring.

Information marked READ is passed through the ring back to the Source - Node B

The information packet is called the Token Frame. The token is called the Token (sometimes referred to as the free token). This can be confusing. Remember, when we talk about a frame, we are talking about data/information. When talking about a token, we are talking about bus arbitration and permission to use the bus.

Introduction to Data Communications
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