ACiDCA7 Comments - Answer Overflow

ACiDCA7

•Created by ACiDCA7 on 4/1/2025 in #help

getting tcp connection state

But the device should be able to establish a new connection

tcp wise most likely but via the protocol to actually talk with the device not. just in case someone else reads this im going to sleep now aswell though

41 replies

CC#

•Created by ACiDCA7 on 4/1/2025 in #help

getting tcp connection state

jeay good night and thank you for the discussion

41 replies

CC#

•Created by ACiDCA7 on 4/1/2025 in #help

getting tcp connection state

aah i forgot to mention that if we dont notice early enough the the device is gone that we produce 100s to 1000s of dollars garbage but ¯\_(ツ)_/¯ not my money

41 replies

CC#

•Created by ACiDCA7 on 4/1/2025 in #help

getting tcp connection state

the conenction will stay in timewait even if device just dies until the timeout. from point of server everything is fine. but then device revives, tries to reestablish a new conenction on same port but cant anymore.. this is the shortest i can explaint it.

or don't understand

jep might be the case... to be honest i had jsut hoped for a quick solution, im currently writing in my free time and dont want to invest too much time into wrok related stuff..xD

41 replies

CC#

•Created by ACiDCA7 on 4/1/2025 in #help

getting tcp connection state

pretty much yea

41 replies

CC#

•Created by ACiDCA7 on 4/1/2025 in #help

getting tcp connection state

i count the app as the application layer.. at some point as you say you get into the session or transport layer

41 replies

CC#

•Created by ACiDCA7 on 4/1/2025 in #help

getting tcp connection state

there were some parameters you could set to set the checkhealthinterval of the tcpsocket. i dont currently have the sourcecode on me so cannot tell exactly how it was done. this will check the tcpconnection on deeper osi level (windows knows about it). if device is gone the conenctionstate goes from established to time-wait. usually couple tries before its completly disconnected. we set that param pretty low, i think it was in the 10s of ms default is somewhere in the multiple seconds iirc. the crux is tho that time-wait is for the tcpsocket still connected while what we want is that if it goes into timewait we know about it to treat it appropriatly

41 replies

CC#

•Created by ACiDCA7 on 4/1/2025 in #help

getting tcp connection state

windows can query conenctionstate on deeper osi level. without the apps knowing anything. then it knows if its established listening whatever

41 replies

CC#

•Created by ACiDCA7 on 4/1/2025 in #help

getting tcp connection state

the problem with the existing dead connection is that like in the case above the connection was just shortly gon

41 replies

CC#

•Created by ACiDCA7 on 4/1/2025 in #help

getting tcp connection state

well what do i send without breaking protocol... how do i know that the connection is gone without sending anything?

41 replies

CC#

•Created by ACiDCA7 on 4/1/2025 in #help

getting tcp connection state

so the safestt bet is to just kill everything and start anew but tcp timeout is not playing nice

41 replies

CC#

•Created by ACiDCA7 on 4/1/2025 in #help

getting tcp connection state

these are all kinds of devices where i dont have really any say in implementation since they come from all kinds of companies

41 replies

CC#

•Created by ACiDCA7 on 4/1/2025 in #help

getting tcp connection state

device looses connection temporarly or whatever, missing packets, when again in range maybe device wants to reconnect thinks has to do handshake again but server didnt had timeout yet -> nothing works anymore

41 replies

CC#

•Created by ACiDCA7 on 4/1/2025 in #help

getting tcp connection state

not always possible... some devices have a specific protocol where no heartbeat is possible

41 replies

CC#

•Created by ACiDCA7 on 4/1/2025 in #help

getting tcp connection state

i do but like written i sadly cannot bet that the connections get closed properly and they will linger as connected until tcptimeout

41 replies

CC#