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Rapid DHCP: Or, how do Macs get on the network so fast? (2011)

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Re: Rapid DHCP: Or, how do Macs get on the network so fast? (2011)

#31

Post by wtallis »

kalleboo wrote: post #8
ams6110 wrote: post #3

Could have been titled: How do Apple devices wreak havoc on home networks. When my kid comes home with his iPhone there is a better than even chance that my home network will go out to lunch. Router reboot time. Never happens with Windows or Android devices coming and going.

If it's "router reboot time" something is seriously messed up with your network. If that's an exaggeration and the iPhone is just booting other random stuff off the network, have you tried just increasing the DHCP lease time? On a home network that just sees the same devices day in and out you could safely set it to several days long.

Really, if your router's uptime isn't measured in months, you're doing it wrong. Probably by running the software it came with, instead of replacing it with an actually-maintained Linux distribution like OpenWRT or LEDE.

There are really very few routers out there anymore that have so little memory they can't be robust and run modern software. Flaky hardware is quite a bit more rare than some users seem to think. The problem is mostly that the hardware vendors have very little incentive to continue polishing the software after the device is shipping, because by the time you get fed up with the consequences of their crap software there will be a new model to sell you. They love that "buy a new router" is such a common troubleshooting step.

Re: Rapid DHCP: Or, how do Macs get on the network so fast? (2011)

#33

Post by 9935c101ab17a66 »

kalleboo wrote: post #10

I remember this feature used to cause a lot of problems with random IP conflicts, but I haven't had an IP conflict like that in years, so it seems they've made it a lot more robust. Or are routers/DHCP servers just less broken these days (I guess since Apple's market share has forced them to)?

I think Apple "updated" the network stack with 10.10 (maybe 10.10.1) and then had so many issues with IP conflicts with the new implementation that they actually backtracked and reverted to the original. The memory is hazy but if you're interested I can do a little digging and see if I can find some other info.

Re: Rapid DHCP: Or, how do Macs get on the network so fast? (2011)

#34

Post by csydas »

ams6110 wrote: post #21
csydas wrote: post #15

Earlier quoted context omitted.

I'd suggest that it warrants more investigation than just writing it off as Apple trashes networks. Hybrid Apple/Windows households have been common for the larger part of 2 decades now and certainly others do not experience the same issues guaranteed. So rather, the title would be Apple devices cause issues on your home network. Or more accurately, something on your home network works in an unintended fashion when y…

It's not just his iPhone. It's iPads, any Apple device that has been "away" for a while and then comes back. TFA describes how Apple is taking shortcuts in the DHCP negotiation. I blame them for assuming that the previous IP address assigned to the device will still be available.

Well, while this may be the case, I'm not quite sure how Apple device assuming same IP as before somehow triggers the disconnect from the rest. It may be part of the steps required to reproduce, but hundreds of other consumer routers with standard configuration handle such a scenario without booting the rest of the attached clients, which is why I woudl rephrase it as unexpected behavior from the router.

And Apple isn't taking a shortcut or a hack here, it's a known scheme: http://www.ietf.org/rfc/rfc4436.txt It's not so much doing anything special as crafting a special call to the network it tries to connect to. It's more of a shortcut to know if the Mac should go to the DHCP phase rather than cheating its way on to the network.

Re: Rapid DHCP: Or, how do Macs get on the network so fast? (2011)

#36

Post by smcl »

colanderman wrote: post #29

This is nice, but kind of useless when waking up from deeper sleep states, which prevent the password dialog from receiving keystrokes for a good five seconds anyway (despite teasing a blinking cursor).

That blinking cursor is especially sneaky. When they just loaded up what is effectively a screenshot while everything loaded, that could've been forgiven (better than a blank screen I suppose). But animating it so that it LOOKS like it's working ...

Re: Rapid DHCP: Or, how do Macs get on the network so fast? (2011)

#37

Post by Hydraulix989 »

RubyPinch wrote: post #20
Nition wrote: post #19

Earlier quoted context omitted.

I'm a bit disappointed that you're downvoted to grey right now because editing obscure config files and entering esoteric terminal commands is exactly why Linux is so difficult for the average user, and it's never going to improve if those who're already comfortable with it ignore the problem.

That's all fine and dandy for the desktop case. But its a dhcp server , network admins would be expected to touch config files, and the interface for a DHCP server really can't be much worse than the GUI version that microsoft supplies! but digressions, to say "this is why I won't use a linux desktop" in response to a server-specific use-case, is at best antagonistic!

It's still a fair point, even if a little "off topic' wrt parent and still perfectly on topic wrt this submission.

Re: Rapid DHCP: Or, how do Macs get on the network so fast? (2011)

#38

Post by matthewmacleod »

ams6110 wrote: post #3

Could have been titled: How do Apple devices wreak havoc on home networks. When my kid comes home with his iPhone there is a better than even chance that my home network will go out to lunch. Router reboot time. Never happens with Windows or Android devices coming and going.

Let’s be clear: this is an issue with your home network. If it’s not able to cope with a known and documented by RFC scheme for detecting network reattachment, then it’s broken.

Unfortunately, most domestic networking equipment is in my experience awful.

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