There is no hard limit imposed by the code on the number of devices that can be attached to the LocalTalk segment. However, the number of devices is limited by the LocalTalk network architecture. If the LocalTalk network is properly repeated or bridged, there could be as many as 254 devices attached to the LocalTalk side of the bridge.
NOTE: The LocalTalk bridge will not function if a router is detected on the LocalTalk network.
"Inside AppleTalk, 2nd Edition" states: "The physical characteristics of the LocalTalk twisted-pair cable allow it to reliably support a recommended maximum of 32 devices." So, without a bridge or repeater, the limit is 32 devices.
However, 20 is the recommended number of devices supported when the bridge is also being used as a workstation. For more devices than that the Macintosh should run as a stand-alone bridge, because there will not be enough computing cycles available to process the user's requests in a prompt manner.
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