Re: 7845i keeps dropping IP connection

["petem" <petem001@xxxxxxxxx>]

"Jim" <alarminex@xxxxxxx> a écrit dans le message de groupe de discussion :
972e3ad2-f6ca-4a03-b6f3-2cf474724cb8@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> On Oct 22, 9:53 pm, "Petem" <petem...@xxxxxxxxx> wrote:
>> "Jim"  a écrit dans le message de groupe de discussion :
>> d930cf88-047c-4940-9511-e53277a46...@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
>>
>> > Sometimes you'll find that there's just "something" about a particular
>> > router that doesn't jive with something on YOUR network but will work
>> > without a hitch on another network with different components.    Go
>> > figure!
>>
>> Totally true, had once a big argument with a network specialist...or
>> so...
>> telling him that his 3com switch had a non compatible auto negociate with
>> my
>> DVR so I could not connect it directly to his switch, the only way to
>> make
>> it work was if I used a small switch (d-link 4 port) between the dvr and
>> 3com switch.
>>
>> the dvr was setup to 100mb full duplex and the switch was allways
>> detecting
>> the dvr as 10mb full duplex.. damn it was hell to make him understand
>> that
>> autonegociate doesnt allways work..after 3 days of email and visit on
>> site
>> (he didnt want the dlink switch to stay there) he finally reprogram the
>> port
>> on the switch to be fix at 100mb full duplex..all was well after that..
>>
>> One other time a customer was using a small network ionterface from dsc
>> to
>> do local  and outside download for a pc4020 and dsl3 for user..
>>
>> the customer was complaining that he was not able to connect to the
>> device
>> during the day.. just at night..
>> That was very strange.. On site I pluged my laptop and started sniffing
>> the
>> packet on the network cable that was going to the device..there was about
>> 30mb/s of broadcast packet going to every computer on the
>> network(broadcast
>> packet are data sent to all device on a network...) But the catch was
>> that
>> the device was a 10mb/s half duplex old thing.. try to send 30,b/s to a
>> 10mb/s device you will overload it and you wont be able to communicate
>> with
>> it..
>> The network guys told me that it was impossible to have that much
>> broadcast
>> on there network. so I made them download ethereal (now wireshark) and
>> they
>> were not knowledgable enough to understand what there were looking at..
>>
>> I had to bring from the shop a laptop I used to debug real nasty problem
>> on
>> network that had computer associate port sniffer ( A damn good program
>> but a
>> bit pricey) then with a pie chart diagram of the packet received on that
>> computer for 10 minute they did understood the obvious..
>>
>> Know what was all this broadcast stuff.. Radio station.. 5 or 6 people
>> were
>> listening to some radio station over the internet..all different one.
>> Usely
>> it should not have created any problem. But here there proxy server for
>> the
>> network were converting Unicast packets to broadcast packets...(Unicast
>> is a
>> way to send only one packets over internet and have it restransmit to
>> every
>> one at once that ask for it..so radio station dont have to send there
>> data
>> to 30000 pople at once (think of the bandwith needed for that!!!)
>>
>> So networking is a strange world.. anything and the inverse can happen
>> and
>> you need some really good alarm tech to understand it..
>
> Sounds like you get into it a lot deeper than I do.
>
> I'm more of a trial and error trouble shooter and if I can't figure it
> out, call the manufacturer tech line. Only do residential and small
> business simple network setups. Router, maybe a switch or two, a few
> computers. I've networked a couple of home automation/whole house
> audio/video systems.  Always setting up from scratch so there's not
> much trouble shooting to do. Most of what I do works the first time so
> I must be doing something right.

Like most people do..

I used to train other tech for tcp-ip, network and ethernet stuff..
All this is pretty obvious if you have a basic training.. the you can build
on it..

Here in Quebec we have training for our members on all this so they can keep
up pace with technology.. one good thing of regulation ;-))))