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NetCon 101 part 5 – The Routing Table, how it is built


aes routing table

You may have heard or read the phrase “Routing Table” when referring to a Subscriber.  This solution explains what the Routing Table is and how it is generated.An AES IntelliNet Subscriber maintains a list of ID’s, up to eight for the purpose of passing its messages or data packets through, in route to the head end or Central Receiver. The list is generated by listening. Any transmission by any other device on the IntelliNet network at the  same frequency and with the same Cipher code that is passed through the Transceiver and decoded by the Subscriber is evaluated. The Subscriber that hears the transmission will extract values contained in the header of the transmission detected.

The extracted information will include the ID of the device currently transmitting the packet along with its Link Layer / Level (LL), NetCon (NC) and Status or fault code. The signal strength of the transmission will also be evaluated. The signal strength evaluation includes whether the Carrier Detect level was reached (CD) and a value that identifies how readable the data was.Upon decoding a packet header, the extracted values are compared with the current list or Routing Table. If the ID is in the list and the values have not changed the Table is left as is.

If there was a change to a value of an ID in the list, the list is modified. If the ID is not in the list, then it is evaluated to determine if it should be in the list. That evaluation includes the signal strength, Status code and whether the LL is equal to or better than what is currently in the list. If the ID rates a place in the list, the list is modified, the Table is sorted and the Subscriber calculates new LL and NC values.

The important thing to take away from this lesson is that the Routing Table is built by listening. Attempts to communicate back to those ID’s in the list, does not occur until the Subscriber has a Data Packet to transmit and only then, if it progresses through the List of ID’s and reaches that ID in the process of using its Routing Table because others in the list before it have failed to have a packet Acknowledge received.

Updated: October 19, 2016 — 7:25 PM

The 10 Deadliest US Hurricanes (1851 – 2006)



What can be said about Hurricanes that hasn’t been said about about a divorce.   They ruin lives are expensive and can be deadly.  The worst hurricane so far hit Galveston  in 1900.  

Apparently city officials never imagined a large hurricane hitting their island so they decided not to build seawalls.      Once things were rebuilt everything was raised 17 feet by bringing in more sand and a large seawall was constructed.  

Below are the top ten worst hurricanes  in the USA since 1851 until 2006.  


1.Great Galveston Hurricane (TX)190048000
2.FL (Lake Okeechobee)192842500
3.Katrina (LA/MS/FL/GA/AL)200531200
4.Cheniere Caminanda (LA)189341100-1400
5.Sea Islands (SC/GA)189331000-2000
7.Audrey (SW LA/N TX)19574416
8.Great Labor Day Hurricane (FL Keys)19355408
9.Last Island (LA)18564400
10.Miami Hurricane (FL/MS/AL/Pensacola)19264372



Updated: October 14, 2016 — 11:35 AM

NetCon 101 Part: 3 – Edition 9 (V 2.6+) vs. Pre Edition 9 (earlier than V 2.6)

Back before UL revision 9 came out the NetCom values  read 0 to 7. 0 being the best and 7 the worst. After the UL Revision 9 changes  the NetCon values changed to  5 to 7.  5 is the best 7 is worst.    A NetCom 5 is needed to pass a fire inspection. The detailed explanation is below. 

A Subscriber developed before the UL 864 9th Edition Compliant models calculate NetCon differently than the later. Edition 9 compliant Subscribers begin at firmware version 2.6+. The firmware version features typically follows all models. If another model is released with a version 2.6+ or higher, it would include the basic Subscriber functions as any other at that version with specific model variations added as needed. Version 2.6+ was designed to operate in a MultiNet environment and still be able to use NetCon 5 to indicate at least two unique paths exist in the current Routing Table all the way to the MultiNet Receiver/7705i.Earlier firmware than 2.6 was developed around the Single RF head end receiver concept, where they would report their NetCon as 0 if the #1 ID in the Routing Table was reporting a Link Layer/Level (LL) of 0.

RF Head End devices such as the 7003, 7703 or a 7170 IP-Link, are the only devices that can report LL as 0. A pre-V 2.6 Subscriber would report itself as a NetCon of 0, because the ID at the top of the list is a LL 0. In other words, if the #1 ID in the list is the single Stand Alone Receiver, it reports NetCon as 0.A V 2.6+ or higher does not report a NetCon of 0 with a LL as 0 in the #1 position. This prevents the reporting of NetCon 0 when a single IP-Link is at the top of the list. Two IP-Links are required to establish a NetCon of 5. Two IP-Links would in fact constitute two unique paths all the way to the 7705i. A third IP-Link would provide three unique paths, but NetCon would still be calculated as 5 adhering to the Edition 9 algorithm’s rules.

Updated: September 11, 2016 — 1:32 PM

How NetCon is calculated for AES radios (PART 2)

How can there be several IDs at the top preference locations in a Routing Table, which have a Good Signal Quality (SQ) and yet have a NetCon of 7?
If NetCon is 7 and there are what appears to be Good SQ IDs at the top of the list, then there is something else that is preventing the Subscriber from considering the ID as Good.It may be that the NetCon of the #1 listed ID has itself got a NetCon of 7. A Subscriber can’t be better than the best (#1) ID listed in its routing table.
It may be that there are some faults being reported by the ID, which are not displayed in the information presented to you.Signal Quality is only one factor in determining if a listed ID is “good” to decrement NetCon.

The list of what is considered good:

Signal above a threshold. (SQ=Good)
No Faults reported. (i.e. low battery, AC fail)
Link Layer better than current LL of this Subscriber.
NetCon is less than 7

Updated: August 24, 2016 — 4:13 PM

How NetCon is calculated for AES radios (PART 1)

I have 6 years experience troubleshooting and programming AES radios and just want so share some information with you guys.  This will cover radio model numbers  7788/7744 , 7706 and 7058.  Explaining how NetCon works does get detailed so I broke it up into 8 parts.  Make sure to scroll all the way to the bottom of this page to see the rest of the parts.



Following is a general explanation of how NetCon is calculated by an AES UL 864, Edition 9 compliant model Subscriber (7744F or 7788F).

aes polling example

  Look at your routing table. What is the Level/Link Layer (LL) of the #1 ID in the list? Is its Signal Quality (SQ) = Good? How many IDs are in the list at the same LL as #1 with a Good SQ? Subtract that number from 7. That should be the NetCon based on that routing table. On Edition 9 compliant units, NetCon will not be lower than 5 even if there are three units at the same Level that are good.Generally, if the SQ is not good, then it is quite possible that the Level was incremented by 1 for the purpose of sorting lower in the list. Sorting is primarily done on the LL.  If there are no Good SQ or all IDs have faults, then the NetCon will be 7.


With one ID at LL 1 and SQ = Good the Subscribers LL should be 2 with a NetCon of 6.With two IDs LL 1 and SQ = Good the Subscribers LL should be 2 with a NetCon of 5.With one IP-Link ID at LL 0 and SQ = Good and another IP-Link ID at LL 0 or 1 with SQ = Marginal the Subscribers LL should be 1 with a NetCon of 6.

 With two IP-Link IDs at LL 0 and SQ = Good the Subscribers LL should be 1 with a NetCon of 5.

 7788F/7744F Rev 1.64Z5 also considers other ID’s in a table listed at a higher Level if it’s NetCon

Updated: August 24, 2016 — 4:05 PM
Big O DFW © 2014
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