Collisions occur on the S-Link bus in the same way they do in any network: where more than one device tries to talk at the same time. A collision could occur between 2 S-Link devices (i.e. CD players) or between the Slink-e and a S-Link device. Like most networks, S-Link devices avoid collisions by waiting until the line is clear before talking. Slink-e obeys the same protocol and doesn't attempt to talk until other devices are done. If two devices attempt to talk simultaneously, a collision can still occur. Slink-e automatically detects collision errors and reports them to you. Additionally, since the Slink-e "loops back" any outgoing messages, you can verify that any message was sent legibly in software. Since the Slink-e has 4 S-Link ports, the likelihood of collisions can be reduced by placing devices on separate ports.