[Dovecot] v2.0.alpha1 released

Timo Sirainen tss at iki.fi
Fri Oct 16 18:32:35 EEST 2009


On Oct 16, 2009, at 7:54 AM, Ed W wrote:

>> Not necessarily. Laptops don't kill existing WiFi connections when  
>> RJ45
>> is plugged into them.
>
> - Wifi and Wired on Windows XP and earlier (possibly vista also?) -  
> now XP does something clever, it appears to have connection tracking  
> in place and once a connection is started on a given interface then  
> that connection continues via the same interface even if the default  
> gateway is changed, ie default gateway only affects new tcp  
> connections and old connections are automatically routed through  
> their initial net device. This allows you to do some funky stuff  
> such as remote controlling a machine over a fast connection whilst  
> getting it to connect to some dialup connection, you can continue to  
> control the machine even after the dialup device is brought up, ie  
> the remote control app doesn't suddenly switch to the new connection.

Do you mean those interfaces would have the same or different IPs?

> I'm not 100% sure, but I think if you kill the wifi connection then  
> actually it will drop all TCP connections on the wifi interface  
> rather than switching them to the wired interface -

Right.

> so I don't think it's actually possible to achieve the effect you  
> described?

What I meant is what happens in most places where I plug in ethernet  
cable while a wireless connection is already there: I get a new IP for  
the wired connection. Then I have two IPs. Only one of the interfaces  
is the default gateway. But there's nothing special going on, all  
connections use their original local IP regardless of how the default  
gateway is changed. If you kill one of the interfaces, all of its  
conncetions will drop.

> Well, I would claim that it's only *important* to *synchronise*  
> communications with a hash of username+IP (where IP is a proxy for  
> communication interface in use on a given device).  I can't  
> immediately see the implications of syncing all communications with  
> a given user, but I think it's possible to be more specific if this  
> is useful?

Yes, the user+ip syncing is important. But I don't see any point in  
adding the +ip part, since user-only syncing is just as good for most  
people and better for a few others.

> Next usecase is:
>
> - In this case I desire to sync IDLE packets for multiple username  
> combinations, but going back to the same IP address, ie actually I  
> want to minimise wakeups per device and per device interface, ie if  
> my 3G card wakes up then I want to get all the data in for all three  
> logins...

Right, this is something that would require ip-only hashing. But I  
think I prefer user-only hashing..

> How can I address this use-case? Perhaps in this case its better to  
> use a single login and make the other accounts shared subfolders of  
> that account?  This isn't something I have tried so far though?

Shared folders would be better typically, I think..


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