jerlands Posted March 31, 2016 Share Posted March 31, 2016 The hop count is NOT related to the retries at all. Hops are the number of times the signals is repeated by devices to extend the range of transmission distance. ACKs are transmitted by the receiving end to acknowledge the command has been received successfully. If the originating device does not receive and ACK signal the originating device may try again and make another attempt. This is a retry and not related to Hops or Hop Count to get to the intended destination. I'm not understanding this correctly... (from post #14) Std-Direct Ack] 16.68.32-->ISY/PLM Group=0, Max Hops=3, Hops Left=2 Doesn't this show the Hops count from the originating device or is the originating device receiving the hops count from the non-end devices ACK transmission? (or neither Jon... Link to comment Share on other sites More sharing options...
larryllix Posted March 31, 2016 Share Posted March 31, 2016 I'm not understanding this correctly... (from post #14) Std-Direct Ack] 16.68.32-->ISY/PLM Group=0, Max Hops=3, Hops Left=2 Doesn't this show the Hops count from the originating device or is the originating device receiving the hops count from the non-end devices ACK transmission? (or neither Jon... I am not 100% sure on this but from your events post that you can have (Max Hops=3, Hops Left=3) I have to assume that the one to one Originator to Target device doesn't count as a hop. soo..... In your example to me this means this. Origin------>DB device(hop)-------->PLM Max Hops=3, Hops Left=2, therefore one hop was done to get to the PLM. ^ ^ ^ | | ------------- Hops left received as 2 = 1 hop used. | --------------Hops left received as 3, resent as Hops left = 2 ---------------Hops left sent as Max Hops = 3 Sounds like an Easter Bunny thing here Edit:bad typo Link to comment Share on other sites More sharing options...
stusviews Posted March 31, 2016 Share Posted March 31, 2016 This excerpt from the Whitepaper may help understanding hops: ... all INSTEON devices are capable of repeating messages by receiving and retransmitting them. Without a mechanism for limiting the number of times a message can be retransmitted, an uncontrolled‘data storm’ of endlessly repeated messages could saturate the network. To solve this problem, INSTEON message originators set the 2-bit Max Hops field to a value of 0, 1, 2, or 3, and they also set the 2-bit Hops Left field to the same value.A Max Hops value of zero tells other devices within range not to retransmit the message. A higher Max Hops value tells devices receiving the message to retransmit it depending on the Hops Left field. If the Hops Left value is one or more, the receiving device decrements the Hops Left value by one, then retransmits the message with the new Hops Left value. Devices that receive a message with a Hops Left value of zero will not retransmit that message. Also, a device that is the intended recipient of a message will not retransmit the message, no matter what the Hops Left value is.Note that the designator ‘Max Hops’ really means maximum retransmissions allowed. All INSTEON messages ‘hop’ at least once, so the value in the Max Hops field is one less than the number of times a message actually hops from one device to another. Since the maximum value in this field is three, there can be four actual hops, consisting of the original transmission and three retransmissions. Four hops can span a chain of five devices. Edit: all devices withing range get the signal at the same time and retransmit at the same time. If ten devices receive the original signal and all ten repeat the signal, the count is still decremented by only 1. Link to comment Share on other sites More sharing options...
larryllix Posted March 31, 2016 Share Posted March 31, 2016 .... A Max Hops value of zero tells other devices within range not to retransmit the message. A higher Max Hops value tells devices receiving the message to retransmit it depending on the Hops Left field. If the Hops Left value is one or more, the receiving device decrements the Hops Left value by one, then retransmits the message with the new Hops Left value. Devices that receive a message with a Hops Left value of zero will not retransmit that message. Also, a device that is the intended recipient of a message will not retransmit the message, no matter what the Hops Left value is Note that the designator ‘Max Hops’ really means maximum retransmissions allowed. All INSTEON messages ‘hop’ at least once, so the value in the Max Hops field is one less than the number of times a message actually hops from one device to another. Since the maximum value in this field is three, there can be four actual hops, consisting of the original transmission and three retransmissions. Four hops can span a chain of five devices. Thanks Stu. That supports the idea I was deriving from the events that a hop is a retransmission and the original to the end device does not count as a hop. That's a lot of signal jumping around with Insteon! It would be good if you had clean comms to be able to lower the system Max Hops to 2 in order to speed up your Insteon Network. This also means that, if the Access Points do not decrement the Hops Left counter, more than a pair of them, could be dangerous for infinitely repeating Insteon signals back and forth. Link to comment Share on other sites More sharing options...
jerlands Posted March 31, 2016 Share Posted March 31, 2016 I have two copies of Insteon details and the older copy doesn't show the sender retransmitting messages but the newer one does. What I'm confused about is Hops Left=(x) and where that value comes from. Is it returned with the ACK, written in route, or the number of retransmissions by the sender? Jon... Link to comment Share on other sites More sharing options...
jerlands Posted March 31, 2016 Share Posted March 31, 2016 If the value Hops Left=0 reflects the number of retranmissions by the sender then it seems possible it took 2 hops to actually reach the receiver but in that time frame another transmission by the sender occurred. Jon... Link to comment Share on other sites More sharing options...
larryllix Posted March 31, 2016 Share Posted March 31, 2016 I have two copies of Insteon details and the older copy doesn't show the sender retransmitting messages but the newer one does. What I'm confused about is Hops Left=(x) and where that value comes from. Is it returned with the ACK, written in route, or the number of retransmissions by the sender? Jon... This may have been answered in Stu's post but... The Max Hops and the Hops Left are sent inside each Insteon packet by the originator. Each hopper subtracts one from the Hops Left count and resends it. When the PLM gets it, the remainder is inside the packet when it receives it. I believe after that, the extra repeats are ignored by ISY and discounted. Link to comment Share on other sites More sharing options...
jerlands Posted March 31, 2016 Share Posted March 31, 2016 This may have been answered in Stu's post but... The Max Hops and the Hops Left are sent inside each Insteon packet by the originator. Each hopper subtracts one from the Hops Left count and resends it. When the PLM gets it, the remainder is inside the packet when it receives it. I believe after that, the extra repeats are ignored by ISY and discounted. Yeah, it makes sense because the message is from the recipient to the sender and wouldn't have record of the senders retransmissions Jon... Link to comment Share on other sites More sharing options...
stusviews Posted March 31, 2016 Share Posted March 31, 2016 I agree. ...Max Hops value tells devices receiving the message to retransmit it depending on the Hops Left field. If the Hops Left value is one or more, the receiving device decrements the Hops Left value by one, then retransmits the message with the new Hops Left value. .. a device that is the intended recipient of a message will not retransmit the message, no matter what the Hops Left value is. So, if the Hops Left is not 0, then devices that are not the intended recipient will retransmit the signal (unless hops remaining is 0), but those signals are ignored. The only record maintained is the hops sent and the hops left. Each device hop counter has no knowledge of the hops count received. The device simple decrements the count by one. Link to comment Share on other sites More sharing options...
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