Timeline for Why token ring uses a physical star?
Current License: CC BY-SA 3.0
13 events
| when toggle format | what | by | license | comment | |
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| Nov 8, 2015 at 17:42 | vote | accept | Utku | ||
| Nov 8, 2015 at 17:40 | comment | added | Ron Maupin♦ | @Utku, breaking the ring, as described in the article, will result in the path having ends (it will no longer be a ring with no ends). That means it is a bus. The end stations will need to know that the ring is broken beyond them so that they can send the token back the way it came instead of continuing on the normal path. This site isn't made for this type of discussion, and you should use Network Engineering Chat for more questions and further discussion. | |
| Nov 8, 2015 at 17:35 | comment | added | Utku | Yes. Multiple non-adjacent failures would break the system in two separate LANs. But can we call it a token bus topology in that case? Because still, two non-adjacent computers on the same LAN cannot directly communicate. It seems like a lines to me. | |
| Nov 8, 2015 at 17:28 | comment | added | Ron Maupin♦ | @Utku The MAU is the ring. If you didn't use a MAU, all the workstations would need to be powered up all the time, and any cable failure would break the ring, essentially giving you a token bus topology (a different IEEE LAN). What is described above (in your question) can handle a single break, but two workstations, opposite each other on the ring, being down would create two separate LANs which are unable to communicate. | |
| Nov 8, 2015 at 17:24 | comment | added | Utku | Oh I see. So token ring is actually not a star physically too. Then the remaining question is: Why token ring couldn't be wired as described in the Wikipedia article? That is: Connecting the nodes in a ring using an inbound and outbound cable between each nodes. Or even using a single cable between each node, provided that the same cable can be used for both receiving and transmitting. This way, we wouldn't need a MAU. (Well, at least on single point failures and/or failures on adjacent nodes.) | |
| Nov 8, 2015 at 17:21 | history | edited | Ron Maupin♦ | CC BY-SA 3.0 |
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| Nov 8, 2015 at 17:21 | comment | added | Ron Maupin♦ | @Utku, I found the picture showing the ring healing. | |
| Nov 8, 2015 at 17:15 | comment | added | Ron Maupin♦ | The MAU has relays at each cable connection point. If the electrical connectivity of an attached cable is broken (broken leg, shutdown workstation, etc.), the relay trips and closes the the cable off from the ring. | |
| Nov 8, 2015 at 17:12 | comment | added | Utku | But how does the MAU bypasses the broken section? From this image, I don't see any way to bypass it. | |
| Nov 8, 2015 at 17:10 | history | edited | Ron Maupin♦ | CC BY-SA 3.0 |
added 1 character in body
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| Nov 8, 2015 at 17:09 | comment | added | Ron Maupin♦ | I grabbed the wrong image. I have multiple versions. | |
| Nov 8, 2015 at 17:07 | comment | added | Utku | Thanks for the image edit. I was confused and on my way to writing a comment for clarification :) | |
| Nov 8, 2015 at 16:59 | history | answered | Ron Maupin♦ | CC BY-SA 3.0 |