I've sat in many a meeting where the Macs "steal" all of the DHCP connections and I'm stuck watching the speaker instead of following TweetDeck.
I've had my wife's macbook bump mine off the network by stealing the IP my machine is using. Definitely an inconvenience when on skype.
Rapid DHCP: Or, how do Macs get on the network so fast?
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Re: Rapid DHCP: Or, how do Macs get on the network so fast?
#12I've sat in many a meeting where the Macs "steal" all of the DHCP connections and I'm stuck watching the speaker instead of following TweetDeck.
I've had my wife's macbook bump mine off the network by stealing the IP my machine is using. Definitely an inconvenience when on skype.
Re: Rapid DHCP: Or, how do Macs get on the network so fast?
#13Earlier quoted context omitted.
ChromeOS is based on linux, so I'd expect something similar to what Android does: userland dhclient with the same performance profile as the tablet he tested.
"Chrome OS" is Gentoo, not Android. One of my friends has a Cr47 and some hacking exposed dhcpcd inside, with some unspecified patching to bring it down to sub-second DHCP.
Re: Rapid DHCP: Or, how do Macs get on the network so fast?
#14Re: Rapid DHCP: Or, how do Macs get on the network so fast?
#15Ok, seriously? That isn't a bug in an implementation somewhere, but in fact a feature that Apple actually is proud of? Am I the only one who finds that if you get a room full of people sitting around with Macs at least one person gets their IP address stolen by someone else?
(edit: I just got downvoted, and then asked the people in the room with me, and they seemed to agree with my perceived correlation regarding the "another computer is using 192.1.0.1" issue... instead of just downvoting, maybe reply? It is actually quite common that DHCP leases on a network get reset for various reasons, and if you just jump on the network without revalidating your lease, you are actually quite likely to just "presumptuously" steal someone else's IP address.)
Re: Rapid DHCP: Or, how do Macs get on the network so fast?
#16Anecdotally, my mac is absolutely horrible at connecting to my wifi. I often have to try multiple times and some times I give up, have to walk over to the router and restart it before I can get on. Probably an issue with the router ultimately, but I don't have this problem with other devices.
Re: Rapid DHCP: Or, how do Macs get on the network so fast?
#17Earlier quoted context omitted.
I've had my wife's macbook bump mine off the network by stealing the IP my machine is using. Definitely an inconvenience when on skype.
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How this works out in the end may depend on the DHCP server in use. Perhaps the server may discover the broken ARP resolution and invalidate the lease, allowing the Mac to jump in and steal the address while the other device is still trying to figure out what happened.
Re: Rapid DHCP: Or, how do Macs get on the network so fast?
#18> This network recognition technique allows the Mac to very rapidly discover if it is connected to a known network. If the network is recognized (and presumably if the Mac knows that the DHCP lease is still active), it immediately and presumptuously configures its IP interface with the address it knows is good for this network. Ok, seriously? That isn't a bug in an implementation somewhere, but in fact a feature that…
And even if it screws this up, it looks like it does a proper DHCP request about a second after the interface comes up, so the problem will be fixed quickly.
Do you have any evidence that Macs in practice tend to inadvertently boot people off the network when they join?
Re: Rapid DHCP: Or, how do Macs get on the network so fast?
#19Interesting on the perspectives here. My macbook is faster at reconnecting than my linux laptop was, but it's still a few seconds. When I'm opening the lid, I typically still need to wait 2-4 seconds before the network is usable, sometimes it's a bit more. In comparison, it's still faster, but not 'instantaneous' as some people seem to suggest. Neither of my macbooks have been "instant" (but again, certainly faster t…
Re: Rapid DHCP: Or, how do Macs get on the network so fast?
#20> This network recognition technique allows the Mac to very rapidly discover if it is connected to a known network. If the network is recognized (and presumably if the Mac knows that the DHCP lease is still active), it immediately and presumptuously configures its IP interface with the address it knows is good for this network. Ok, seriously? That isn't a bug in an implementation somewhere, but in fact a feature that…
Why would that be the case? Assuming it only does this if it knows its previous DHCP lease hasn't run out, it's very likely (unless the DHCP server has been rebooted or has otherwise lost its lease table) that no other device is using that IP. And even if it screws this up, it looks like it does a proper DHCP request about a second after the interface comes up, so the problem will be fixed quickly. Do you have any ev…
(and yes: some routers hold on to only a certain number of inactive leases, and routers actually do get rebooted in home, office, and hotel environments quite often, crossing the boundary of the 1-2 day leases that are often given to clients.)