[CentOS] Is avahi essential?

Les Mikesell lesmikesell at gmail.com
Sat Jan 14 17:01:23 UTC 2012


On Sat, Jan 14, 2012 at 8:57 AM, Marc Deop <damnshock at gmail.com> wrote:
>>ARP: In a traditional ethernet network, when you try to connect to a
>>machine on your local network with the number 10.20.30.40 then your
>>machine will send out an ARP broadcast packet "whois 10.20.30.40" and
>>then the machine in question will respond with its MAC address and then
>>the machines can talk via ethernet.
>
> Ain't it the router the one that responds?

No, the device with the IP responds directly.

> I mean, it usually has an ARP table to speed up things ;)

Everything keeps an arp cache so they don't have to repeat the lookup
for every packet, but routers expect to talk to a lot of devices and
hold the cached pairs longer - perhaps up to 20 minutes.   Most other
devices have very short timeouts so they'll notice an IP change more
quickly.

-- 
   Les Mikesell
    lesmikesell at gmail.com



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