How fast device feature of BACRouter improves MSTP token pass rate?

The test criterion is: 115.2kbps, 80m cable. 1 router and 10 mstp master devices, max_master=127, no NPDU traffic on bus, define non used mac as fast device.

Router mac

Fast device timeout config

Other device’s mac

Token pass rate(round/min)

Percentage Base no fast

127

—-

117~126

2301

100%

127

0ms

117~126

4856

211%

127

1ms

117~126

4734

206%

127

2ms

117~126

4473

194%

116

0ms

117~126

4690

204%

116

1ms

117~126

4577

199%

116

2ms

117~126

4343

189%

58

—-

117~126

1777

100%

58

0ms

117~126

4563

257%

58

1ms

117~126

4405

248%

58

2ms

117~126

4071

229%

110

—-

0,11,22,33,44,55,66,77,88,99

1153

100%

110

0ms

0,11,22,33,44,55,66,77,88,99

4037

350%

110

1ms

0,11,22,33,44,55,66,77,88,99

3813

331%

110

2ms

0,11,22,33,44,55,66,77,88,99

3393

294%

BACRouter Changelog

Old Firmware

4.15 2021.9.15 Download

Modbus: more convenient Master/Slave copy.

Modbus: supports batching modify slave’s Modbus parameter.

Modbus: MultiState objects could be mapped from bit range in a register.

4.14 2021.8.25 Download

There is a bug on rescue upgrade that old configuration is not deleted which may prevent WebUI from loading.  If old version WebUI could not be loaded because of invalid configuration, please rescue upgrade to this version twice, first time it will upgrade firmware, the second time it will delete old configuration.

A bug on Modbus virtual device mode is fixed which cause malfunction when virtual devices are more than 5.

A WebUI bug when Modbus slave number overflowing limitation is fixed.

The limiations of Modbus master and slave are changed from 100 to 128.

A WebUI bug when disabling “Packet capture mapping” is fixed.

More name delimiter characters are added. Internal object names are modified to avoid collision with new name delimiter characters.

4.13 2021.8.5  Download

Modbus slave settings add “Batch Address” functionality.

Move MS/TP “Extended frame” option to extended configure mode.

4.12 2021.7.23  Download

A long time bug from 3.x on ms/tp may cause ms/tp port stop working.

4.11 2021.7.16

There is a bug in 4.10 introduced by MS/TP timing revision,  which is caused by higher compiling optimization.

4.10 2021.7.13

BACnet protocol revision is changed to 16

Polarity in binary value object is proprietary property.

MS/TP timing revision for padding byte.

Modbus master: Batch Point, Batch Instance, Batch Import

Modbus slave: Import Point

Modbus master/slave: UI for copy and  move up/down.

4.09  2021.7.02  Download

Compatible to new hardware revision.

BTL compatibility: max_info_frames/max_master are writable from BACnet side.

4.08  2021.6.22

BTL 10.2.3.6 requires routers sending who-is-router-to-network to looking downstream router before reject messages.

Bugs which will be triggered when VBUS is enabled have been fixed.

4.07  2021.6.13

UI bug introduced in 4.05 may prevent user to access WebUI in certain situation. (Please note that http://IP/app/upgrade is a rescue entry to upgrade firmware)

Some minor UI bugfixs.

4.05  2021.6.7

Modbus object name remove top level “modbus_master”.

Object name delimiter “|” become configurable.

Value object is allowed to overlap with output object.

Some UI bugfixs.

4.04  2021.6.1

Lots of update on Modbus Gateway module: Multistate object, Value object, Binary text, Read group, Batch conversion, Import/Export CSV object definition.

Convert BASgatewayLX CSV Configuration To BACRouter JSON

4.03  2021.4.23

Modbus Gateway

Offline Configuration

3.23  2021.3.19

Bugfix for BACnet mapping module for capture control feature. The bug may cause daemon restart if capture is restarted from BACnet side.

Bugfix for max_apdu_length_accepted for outgoing request on ms/tp if extended frame feature not enabled.

More infos including “total/free memory”/”Booting time” are added into “System Settings” page on WebUI.

3.21  2021.2.22

Bugfixs for mstp slave proxy: daemon segfault&restart when binding removing. Incorrect hop count when send I-Am reply on other ports.

Reply APDU and network reject messages should respect busy status of destination net too.

3.20  2021.1.26

Limitation of creating network port is removed, only total network port rule applies now. It’s more easy for user to adjust and switch configuration of port.

If root password has not been set yet, the button to set root password on “System Settings” page will has red color to remind user.

3.19  2021.1.20

 Soc bug that prevent MS/TP from startup will occasionally be triggered on 3.18

3.18  2021.1.18

MS/TP add “Extended frame” option.

Reject-Message-To-Network should be unicasted to compliant to BTL.

TTL of registered foreign device should plus 30 seconds to compliant to BTL.

Confirmed service sent to broadcast address should be dropped on application layer to compliant to BTL

BBMD should drop unicasted forwarded npdu from local subnet with same udp port.

Bug on multiple BBMD detection when checking existence of entry in BDT with different udp port is fixed.

3.17  2021.1.13

WebUI adds network settings page, which will show routing table.

A bug on slave proxy is fixed: when there is a unicasted who-is send to slave device, the device instance range carried by the service should be respected, same as broadcasted one.

3.15  2020.10.26

MS/TP duplicate detection algorithm which is learned from duplicating of JCI FEC2611 and IOM3731 is added.

3.14  2020.10.23

MS/TP duplicated MAC detection is implemented. Duplicated MAC will be shown by Red color in “Recently active other devices”. Because of complexity of behavior on duplicating situation, the detection is inaccurate and for reference only.

A potential bug introduced from 3.0 in the low level MS/TP state machine is fixed.

3.13  2020.10.5

Based testing and clients’ feedback, many(maybe most) devices does not obey the MS/TP receive frame finite state machine described in BACnet standard when they encounter error.  Our proprietary “Timeout Interrupt” feature will cause trouble or degrade performance in this situation.  So “Timeout Interrupt” feature is removed.

More statistics is added to MS/TP runtime information page.

WebUI bug on BIP’s Foreign Device Mode introduced from 3.08 is fixed.

3.11  2020.7.14

Fix mstp calculation bug on time used for invalid packet.

Fix bug on mstp slave proxy introduced by 3.08

Some minor WebUI improvements.

3.10  2020.7.1

The config file format is changed much between 2.x and 3.x,  so from 3.00 to 3.09, when upgrade firmware, the upgrading script will install new config file.  This version add a “Keep config” option when upgrade firmware. If config file have something wrong, the WebUI will popup a warning when it is opened.

3.09  2020.6.30

Fixs bug introduced in 3.08 when fetch mstp runtime info.

Some minor WebUi improvements.

3.08  2020.6.28

Bugfix: 1 hop broadcast distribution is optional for BBMD, From version 3.00, BACRouter force other BBMDs to use 1 hop distribution if cross-network broadcast support is enabled. It’s incorrect behavior and fixed in this version.

BDT editing UI is improved. When submitting, BDT entries will be checked to detect possible misconfigure. The checking is also taken when receiving Write_BDT BVLL message.

If multiple BBMD support is not enabled, when receiving forwarded npdu from BBMD not present in local BDT, the npdu will be dropped and logged. It will help distinguishing configure problem of BBMD on most situation. “Report multiple BBMD” function in last verion is covered by this function, so it’s removed.

The filename of downloaded config is set as IP_Version.json, for example: 192.168.100.1_3.08.json

Config uploaded from file will be edited in WebUI before saving to eliminate any potential incompatibility.

3.06  2020.5.22

Ethernet is disabled by default. If BIP and Ethernet are enabled at the same time, a warning of possible circular route will be promoted.

The default capture size increases to 4M.

3.05  2020.5.15

Capture control function is mapped to BACnet.  Each datalink port has its “Capture buf_size” and “Capture command” Multi_State_Value. “Capture buf_size” could be set between “64K” to “16M”. “Capture command” could be set between “Stop&Clean”, “Start”, “Stop”.

3.04  2020.4.28

Password for root could be modified from WebUI now.

3.03  2020.4.23

BACRouter verifies other router’s live by query its routing table with Initialize-Routing-Table message. But addendum 135-2012AL removed the enforced supporting of Initialize-Routing-Table from router. So in this version BACRouter also monitors Reject-Message-To-Network message that could only be sent by router.

BIP BVLL header of forwarded npdu is 6 bytes larger than other npdu, so there was potential bug on packet length verification that is fixed on this release.

3.02  2020.3.26

Minor bugfixs for UI

3.01  2020.3.17

“Download config” and “Upload config” are added to “System setting”

3.00  2020.3.10

Add Packet capture feature:

Supported on all ports(Ethernet, BIP, MSTP).

Because Wireshark could not decode MSTP extended frames, MSTP extended frames are converted to traditional data frames. Fortunately, Wireshark doesn’t complain about overflowed data length.

MSTP packet could be downloaded as “Interval format”. it could be used to show exact idle time before packet by selecting “Seconds Since Previous Captured Pakcet” as “Time Display Format” in Wireshark. It is very helpful to analyze timing and performance problem.

Continuous download is supported. Automatic traffic logging is possible with the API.

MSTP auto addressing feature is removed.  Because the same time online for all devices could not be guaranteed, there is no perfect auto addressing solution. To help determine max_master and unused MAC on bus, “Sniffer mode” may be enabled, then “Current max master” could be obtained from run time info. Unused MAC also could be chosen referred to “Recently active devices”.

MSTP support real time analysis for max master and show it on run time info, if the value is not matched to the setting, “unmatched” is showed after it.

MSTP support sniffer mode. it could analyze and record data without interfering the bus.

The WebUI of MSTP port add options for basic mode and extend mode.

The timeout settings for MSTP are changed from Integer to Float.

MSTP port’s slave proxy is only support broadcasted Who-Is in previous version. Now it support unicast too.

MSTP port’s slave proxy send unicasted I-AM instead of broadcasted one in previous version.

There is a bug in previous version that Who-Is packet readed by MSTP slave proxy module bypass source address routing verify. it’s fixed this time.

BBMD module add option to log error when multiple BBMDs are found in local lan.

Modify feature introduced by version 2.17. “Accept unmatched destination IP” option is provided, if it is selected, only warning message will be logged, else error message will be be logged and the packet will be dropped.

Many WebUI improvements.

2.18  2019.4.16

Improved IP&Ethernet processing performance.

Process 0 in unconfirmed COV notification service is reserved for unsubscribed notificationCOV. Not longer reports error when can not find matched process for 0.

2.17  2019.4.2

In previous version, when BACRouter receive Original-broadcast BVLL from unicast address or Original-unicast BVLL from broadcast address, it would print error message then drop it.  A customer reported that Johnson Controls’ CCT sends Original-broadcast BVLL to unicast address, so now we only print warning message.

2.16  2019.2.25

From version 2.0.8,  only proprietary network layer messages would be relayed. Now all unknown network layer messages will be relayed.

2.15  2017.10.19

Redirect URL from “/” to “/?” to support Edge web browser (avoid keep asking authorization)

MSTP: Fix bug in standard state machine which would cause passing token to self when duplicated token is found.

MSTP: With standard state machine device in sole master mode would send max_info_frames * Npoll frames after polling one master. A more reasonable behavior is implemented that device send max_info_frames * Npoll frames after finish polling all masters.

2.14  2017.10.13

Fixed bug introduced from 2.0, it should not wait reply when it send expecting reply request to mac address 255 on MSTP.

2.13  2017.9.19

Potential bug (barely) may be triggered if MSTP auto mac and baudrate forcing are enabled together.

2.12  2017.7.10

Optimizing route entry protection: Deletion from route hop will bypass protection.

Support devices utilizing 6.5.3 methods 1 and 4 for establishing the address of a BACnet router for a particular DNET.

2.11  2017.6.16

This update help building up routing table quickly in large BACnet inter-network.

When BACRouter startups, it broadcasts out Who_Is_Router_To_Network without network number specified to learn routing info from other routers.

When Who_Is_Router_To_Network/Router_Busy_To_Network/Router_Available_To_Network without network number specified is received, BACRouter reports network number up to 1120 instead of 112 in previous version.

2.10  2017.6.13

Bugfix: ReadRange on property_list should not return object_identifier; object_name; object_type.

Delay 1 second for sending Network_Number_Is when router startup, because if router is a BIP foreign device, the foreign device registering have not completed yet.

2.09  2017.6.10

Protect route entry 60 seconds from last activity. Avoid broadcast storm in circular routing path.

2.08  2017.6.7

Bugfix: Vendor proprietary network message should be correctly relayed.

When relay Reject-Message-To-Network with reason 4(Too long), use unicast address instead of broadcast address.

Relax daemon’s max_apdu_retries to 10, in accord with WebUI.

2.07  2017.6.5

Compliant to BACnet Router and BBMD device profile.

Try to purge invalid route entry if no reply is received for Who_Is_Router_To_Network or Initializing_Routing_Table. This feature helps to rescue from mess network configuration.

Avoid sending too many I_Am_Router_To_Network with circular routing path.

Reduce memory consumption in complicated inter-network.

2.06  2017.6.1

Avoid BBMD broadcast storm. If Forwarded-NPDU is received from broadcast address, do not re-broadcast it.

When relay Reject-Message-To-Network with reason 1/2/4, use broadcast address.

Discard Reject-Message-To-Network with incorrect route info.

Check source net of incoming NPDU.(Trickily handle Initializing-Routing-Table)

2.05  2017.5.23

Bug: global broadcasted initializing-routing-table should be executed.

Bug: WebUI BIP mode select should not be applied without submiting.

Limit number of route entry in runtime info page to avoid request failure in very large internetwork.

2.04  2017.5.11

Fix WebUI Bug for verifying BDT.

Save configuration and restart when receive reinitialize-device service request.

2.03  2017.5.7

BIP BBMD NAT mode support udp port modifying.

BIP BBMD NAT mode do not listen to local net broadcast address and not send broadcast to local net.

BIP foreign device mode do not listen to local net broadcast address.

2.02  2017.5.5

Regards device sent Who-Is-Router-To-Network has no route to that network.(Delete that route entry from route table)

When Initializing-Routing-Table request modify network number of route port, I-Am-Route-To-Network is sent to report new network number.

Fix bug introduced by ver2.0 for saving new BDT modified by BVLL Write-Broadcast-Distribution-Table message.

2.01  2017.5.3

Add upgrade entry “http://ip/app/upgrade for rescue.

More intuitive log.

Improve network reject behavior.

Fix overflow bug when send I-Am-Router-To-Network(if network numbers reported > 738).

Sending I-Am-Router-To-Network at dynamic time interval.

2.0  2017.4.19

Option to enable Device object inside router.

Allow setting modification from BACnet side.

Support What_is_Network_Number and Network_Number_Is message

Option to support MSTP max_info_frames by occupy time.

Introduce MSTP new concept of auto/forced baudrate.

Guarantee of MSTP message delay(10 seconds).

WebUI is more intelligent.

1.22  2016.10.26  Download

Increase max route table entry from 1024 to 65534(unlimited).

1.21  2016.10.18

Slave Proxy: Increase ReadProperty(Multiple) sending rate if remote device is fast device.

BVLL response NAK for BBMD-related BVLL request but BBMD is not enabled. (Addendum 135-2012ax-5)

BVLL response NAK Upon receipt of a Distribute-Broadcast-To-Network message from a un-registered foreign device. (Addendum 135-2010ad-10)

1.20  2016.10.8

BIP provide option to accept buggy broadcast to 255.255.255.255

Reduce minimum value of register interval for BIP Foreign Device Mode from 30 seconds to 15 seconds.

1.19  2016.9.23

Change webui reboot to restart, if IP/Netmask/Gateway/DHCP is not changed, fastly restart self

MSTP add fast device timeout interrupt feature

MSTP fast device minimums timeout is set to 0ms (actually 1.5bits plus 50us after turnaround)

MSTP fast device minimums token pass timeout is limit to 20ms

MSTP runtime info shows devices is active in past 10 seconds

1.18  2016.9.13

BIP BBMD support NAT, add two config parameter: “Accept BDT push from other” and “Accept foreign device register”.

Show Ethernet MAC address on “Setting” page.

1.17  2016.9.8

Requested by some OEM customer, now login authorization domain could be customized when place order.

1.16  2016.9.7

Bugfix: slave proxy should not response to who-is from port that device is not proxied on.

Bugfix: write to remote BBMD BDT fail

Lots UI improving.

1.15  2016.9.1

New slave proxy feature.

MSTP add no_turn_around frame count and padding frame count diagnosis information.

Some UI improved.

Fix decode bug when no turnaround frame following a padding frame.

1.14  2016.8.24

It’s a big release, many new features and bugfix:

MSTP add setting for Treply_timeout and Tusage_timeout.

MSTP add fast device feature, allow user define some nodes as fast device, apply as short as 1 milliseconds to Treply_timeout and Tusage_timeout

MSTP add more diagnosis information as: mac conflict frame count, send conflict count, token lost count, pass token fail count, reply timeout count, frame error count, token duplicate count.

MSTP enhance compatible to some devices no respecting 40bits turnaround requirement.

MSTP fix bug decode extended frame.

MSTP fix bug calculate test response header crc on specified situation.

1.13  2016.8.16

Low level api change, not affected.

1.12  2016.8.12

Add serial no.

1.11  2016.8.10

Firmware filename has version and crc.

Show version on left tree menu.

Auto refresh page after reboot or firmware upgrade .

Other UI bugfixs.

Bandwidth of BACnet MSTP

A common problem of BACnet MSTP is low bandwidth utilization. Some researches disclose that more than 50% traffic on MSTP bus is token frame.

Unfortunately, many poor implement of MSTP make it worse. For example, in standard, the Tturnaroud is 40 bits, that is said, on 115200bps, node only need to wait 0.35 millisecond to send frame when it receive token. But in practice, there are a lot of devices wait at lease several milliseconds.

Our implement of MSTP try best to improve bandwidth. In previous laboratory test, we achieve 98.8% bandwidth utilization on our BACnet router. The test criterion is:

115200bps, 4 node with mac address from 0 to 3, max_master set to 3, no NPDU. in theory, the max token relay rate is 960 per seconds. we get 948 per second.

In another test, we send a read property request (23 bytes frame) each second, then get a Reply_Postponed frame, then a  read property response (29 bytes frame). we still get token relay rate of 943 per second.

Update Feb, 2017, We make a stress test for ReadProperty service on above configuration, set max_info_frames to 10 in all devices, 2 devices request, the other 2 devices reply. The result is 153~154 ReadProperty requests are served each second.

Update March,2017. Thank to our detailed runtime info, user could get token pass rate easily. 9 months after we release first firmware, We perform above test again, then get 956.6 per second, 99.6% bandwidth utilization.