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Battery saving tip - really works!

That's not the way DHCP works. If the phone is responding to DHCP queries from the router, as you suspect, that would happen whether or not it was a permanent/static DHCP lease. It's not like the normal lease is 60 seconds or something, they are probably at minimum 24 hours (probably longer).

So, if DHCP is the problem you described, then the ONLY solution would be to change the phone from DHCP and enter an IP address manually.

Fair enough. I know how to set up a wireless network and the difference between DHCP and static IPs, but I don't know much about the underlying technologies/protocols.

Cheers.
 
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Based on what the OP posted, using "DHCP Static" would have the same battery problem as DHCP. DHCP Static is not the same as setting a static IP on the phone (or other device). Instead, it's simply setting up a permanent DHCP lease on the router. Meaning, the device still looks to the router as the DHCP server to assign it an IP (the device is setup for DHCP). However, any time the device needs to be assigned an IP (every time it connects to the router or when a lease expires), the router gives it the same IP.

This is an alternative to using a true static IP, but it is still a DHCP IP and behaves as a DHCP IP in all ways.

So, if there truly is a battery hit for using DHCP, you will see the same battery hit using DHCP static.
haha, still confused. So my phone is .194, and on here someone said 101-253, so does that mean my is already static or a mix etc? Just trying to figure out what I have to change and do to test, I'm good with electronics right down to having an awesome home theater and media streaming... but when it comes to routers I just setup and that's it lol.

Are you changing it directly at the router accessed at the IP address, or just going to wifi -> advance -> change DHCP to Static?
 
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You have to configure your router too.
how do you do that specifically for the phone? Do you just change it to static as well, I have the dir-655 extreme. No clue as to what numbers etc you should enter for the address? Read you should enter different addresses in from before but no sure what that means, my phone autofilled the ip, gateway, dns etc. Connection on the router says DHCP Client for all (computers, phones etc)

Great with electronics, except for routers, I just set them up and leave as is lol

edit - in the network settings on router, won't let me change anything, offers to reserve/revoke the ip. But if I got to add a new one in and say use 194.168.0.202 to be outside of DHCP range it still says to make sure the address is within range (100-199).
 
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You have to configure your router too.

There is nothing to configure in the router for a static address on a device (phone or otherwise).

I won't have my S3 until tomorrow to know exactly what the menus are, but on Android 2.4 you would go to wireless settings, click menu > advanced, click "Use static IP" (which says below it "manually configure IP settings" and then put in your IP address, gateway and netmask.

Surf said he clicked that and it filled in his info for him, which is possible. Regardless if it fills it automatically, or you enter it, at that point that is the ONLY IP it will use. It no longer looks to the router for an IP, so there is NOTHING to configure on the router.

The only thing you need to do is make sure that the static IP manually entered into the phone is not within the range the router is using for DHCP.

Surf, it doesn't matter what IP you use on your phone, whether it's .194 or something else, you just want to make sure it's not within the range your router is using for DHCP. The only reason for avoiding that is because your router could then give the same IP to another device on your network and then you will get an IP address conflict. So, since you say the router is using 100-199 for DHCP, you want to use something below or above that for your static IP. You don't need to enter the IP address you choose in the router, just key it into your phone, something like .210 or something.
 
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There is nothing to configure in the router for a static address on a device (phone or otherwise).

I won't have my S3 until tomorrow to know exactly what the menus are, but on Android 2.4 you would go to wireless settings, click menu > advanced, click "Use static IP" (which says below it "manually configure IP settings" and then put in your IP address, gateway and netmask.

Surf said he clicked that and it filled in his info for him, which is possible. Regardless if it fills it automatically, or you enter it, at that point that is the ONLY IP it will use. It no longer looks to the router for an IP, so there is NOTHING to configure on the router.

The only thing you need to do is make sure that the static IP manually entered into the phone is not within the range the router is using for DHCP.

Surf, it doesn't matter what IP you use on your phone, whether it's .194 or something else, you just want to make sure it's not within the range your router is using for DHCP. The only reason for avoiding that is because your router could then give the same IP to another device on your network and then you will get an IP address conflict. So, since you say the router is using 100-199 for DHCP, you want to use something below or above that for your static IP. You don't need to enter the IP address you choose in the router, just key it into your phone, something like .210 or something.

Man, I just could not find this option in my S3. I'm afraid you can't do this way
 
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There is nothing to configure in the router for a static address on a device (phone or otherwise).

I won't have my S3 until tomorrow to know exactly what the menus are, but on Android 2.4 you would go to wireless settings, click menu > advanced, click "Use static IP" (which says below it "manually configure IP settings" and then put in your IP address, gateway and netmask.

Surf said he clicked that and it filled in his info for him, which is possible. Regardless if it fills it automatically, or you enter it, at that point that is the ONLY IP it will use. It no longer looks to the router for an IP, so there is NOTHING to configure on the router.

The only thing you need to do is make sure that the static IP manually entered into the phone is not within the range the router is using for DHCP.

Surf, it doesn't matter what IP you use on your phone, whether it's .194 or something else, you just want to make sure it's not within the range your router is using for DHCP. The only reason for avoiding that is because your router could then give the same IP to another device on your network and then you will get an IP address conflict. So, since you say the router is using 100-199 for DHCP, you want to use something below or above that for your static IP. You don't need to enter the IP address you choose in the router, just key it into your phone, something like .210 or something.

That's what I meant. You need to make sure the IP address isn't in the dhcp range otherwise there can be conflicts where devices get kicked off the network because a new device gets assigned that IP.

If this is happening then the phone could be using the mobile network whenever its getting kicked off, which will of course not save battery.
 
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Originally Posted by tnedator<br />
There is nothing to configure in the router for a static address on a device (phone or otherwise). <br />
<br />
I won't have my S3 until tomorrow to know exactly what the menus are, but on Android 2.4 you would go to wireless settings, click menu > advanced, click "Use static IP" (which says below it "manually configure IP settings" and then put in your IP address, gateway and netmask. <br />
<br />
Surf said he clicked that and it filled in his info for him, which is possible. Regardless if it fills it automatically, or you enter it, at that point that is the ONLY IP it will use. It no longer looks to the router for an IP, so there is NOTHING to configure on the router.<br />
<br />
The only thing you need to do is make sure that the static IP manually entered into the phone is not within the range the router is using for DHCP.<br />
<br />
Surf, it doesn't matter what IP you use on your phone, whether it's .194 or something else, you just want to make sure it's not within the range your router is using for DHCP. The only reason for avoiding that is because your router could then give the same IP to another device on your network and then you will get an IP address conflict. So, since you say the router is using 100-199 for DHCP, you want to use something below or above that for your static IP. You don't need to enter the IP address you choose in the router, just key it into your phone, something like .210 or something.
<br />
<br />
Man, I just could not find this option in my S3. I'm afraid you can't do this way
 
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There is nothing to configure in the router for a static address on a device (phone or otherwise).

I won't have my S3 until tomorrow to know exactly what the menus are, but on Android 2.4 you would go to wireless settings, click menu > advanced, click "Use static IP" (which says below it "manually configure IP settings" and then put in your IP address, gateway and netmask.

Surf said he clicked that and it filled in his info for him, which is possible. Regardless if it fills it automatically, or you enter it, at that point that is the ONLY IP it will use. It no longer looks to the router for an IP, so there is NOTHING to configure on the router.

The only thing you need to do is make sure that the static IP manually entered into the phone is not within the range the router is using for DHCP.

Surf, it doesn't matter what IP you use on your phone, whether it's .194 or something else, you just want to make sure it's not within the range your router is using for DHCP. The only reason for avoiding that is because your router could then give the same IP to another device on your network and then you will get an IP address conflict. So, since you say the router is using 100-199 for DHCP, you want to use something below or above that for your static IP. You don't need to enter the IP address you choose in the router, just key it into your phone, something like .210 or something.
Yeh that's what I tried last night and today again and it doesn't work, if I enter 192.168.1.210, the ip in the router still shows 192.168.1.194 and wifi will say connected on phone but can't browse or anything (no connection). And if I put back 192.168.1.194 in the phone it doesn't work anymore even though it shows on the router, have to restart the phone then it connects fine.
 
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Yeh that's what I tried last night and today again and it doesn't work, if I enter 192.168.1.210, the ip in the router still shows 192.168.1.194 and wifi will say connected on phone but can't browse or anything (no connection). And if I put back 192.168.1.194 in the phone it doesn't work anymore even though it shows on the router, have to restart the phone then it connects fine.

What does the IP address say when you go to Settings > About Device > Status ?
 
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What does the IP address say when you go to Settings > About Device > Status ?
Either or, if I don't change it it says .194, if I change the ip to .210 or whatever it reflects that change and will say it's connected but can't browse etc

But the router will still show the device as .194

edit - restarted the phone and it seems to work on .210 and shows that as static ip on the phone, but the router still shows it connected as dhcp .194
 
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Either or, if I don't change it it says .194, if I change the ip to .210 or whatever it reflects that change and will say it's connected but can't browse etc

But the router will still show the device as .194

edit - restarted the phone and it seems to work on .210 and shows that as static ip on the phone, but the router still shows it connected as dhcp .194

Try changing the setting in your router too.

There should be a section for configuring LAN clients - go there and you should be able to assign a static IP address to a MAC address that's connected to the network. You can find your phone's MAC address in the same place you found the IP address.
 
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Try changing the setting in your router too.

There should be a section for configuring LAN clients - go there and you should be able to assign a static IP address to a MAC address that's connected to the network. You can find your phone's MAC address in the same place you found the IP address.
What's weird is the phone works now, and shows the static ip entered.... however the router doesn't reflect it at all, the device doesn't even show up on it yet it works fine online??? :thinking:
 
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What's weird is the phone works now, and shows the static ip entered.... however the router doesn't reflect it at all, the device doesn't even show up on it yet it works fine online??? :thinking:

Hate to sound like a broken record, but...

DO NOT WORRY ABOUT THE ROUTER if you have your phone set to a static IP. As long as your static IP is out of the DHCP range on the router (which .210 is), then you are fine.

What you are seeing on the router is the DHCP lease that hasn't expired. What that is showing is that if your phone (based on it's MAC address) was to reconnect to the router with the phone set to DHCP (not static) then it would be assigned the .194 address. That IP is currently reserved for your S3. At some point the DHCP lease will expired and then that will leave the list.

I'm not familiar with that linksys, so I can't tell you exactly, but typically routers show a setup of DHCP reserved IPs and a list of actually connected devices. It's possible that the linksys doesn't separate them, but regardless, if you are using a static IP outside of your DHCP range, you simply don't have to worry about what the router says and SHOULD NOT change it in the router to the .210 IP, because that's outside of the DHCP range.

So, in summary, ignore the router, don't change anything in it. Have your phone set to static with the .210 IP, and you are good to go with a static IP.

Whether or not it improves battery life is a different issue, but doing the above and you will be static and the phone will not contact the router for DHCP info.
 
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Hate to sound like a broken record, but...

DO NOT WORRY ABOUT THE ROUTER if you have your phone set to a static IP. As long as your static IP is out of the DHCP range on the router (which .210 is), then you are fine.

What you are seeing on the router is the DHCP lease that hasn't expired. What that is showing is that if your phone (based on it's MAC address) was to reconnect to the router with the phone set to DHCP (not static) then it would be assigned the .194 address. That IP is currently reserved for your S3. At some point the DHCP lease will expired and then that will leave the list.

I'm not familiar with that linksys, so I can't tell you exactly, but typically routers show a setup of DHCP reserved IPs and a list of actually connected devices. It's possible that the linksys doesn't separate them, but regardless, if you are using a static IP outside of your DHCP range, you simply don't have to worry about what the router says and SHOULD NOT change it in the router to the .210 IP, because that's outside of the DHCP range.

So, in summary, ignore the router, don't change anything in it. Have your phone set to static with the .210 IP, and you are good to go with a static IP.

Whether or not it improves battery life is a different issue, but doing the above and you will be static and the phone will not contact the router for DHCP info.
yeh I'll see tomorrow as far as battery life, seems to be fine staying connected. I know before it would disconnect and reconnect few times a day randomly. Hasn't seemed to of done that since changing it to static.
 
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Well haven't seen any difference, standby and use are basically the same. Maybe it only works with certain phones?

Maybe you didn't have the wakelock in the first place? It could depend on the network configuration.

This tip is for those who are suffering from a "wlan_rx_wake" wakelock which is keeping the phone awake for hours at a time.
 
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Maybe you didn't have the wakelock in the first place? It could depend on the network configuration.

This tip is for those who are suffering from a "wlan_rx_wake" wakelock which is keeping the phone awake for hours at a time.

How would one diagnose if their phone is affected by this wakelock condition? I don't have my S3 yet (Verizon), but would like to know more about this just in case I need it later. In the OP it was stated "I have BetterBatteryStats installed and checked the kernel wakelocks. I was getting a "wlan_rx_wake" wakelock which was causing 92% of my kernel wake locks." So would I have to install BetterBatteryStats and look there to see if this condition existed?
 
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How would one diagnose if their phone is affected by this wakelock condition? I don't have my S3 yet (Verizon), but would like to know more about this just in case I need it later. In the OP it was stated "I have BetterBatteryStats installed and checked the kernel wakelocks. I was getting a "wlan_rx_wake" wakelock which was causing 92% of my kernel wake locks." So would I have to install BetterBatteryStats and look there to see if this condition existed?

That's right :)
 
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Maybe you didn't have the wakelock in the first place? It could depend on the network configuration.

This tip is for those who are suffering from a "wlan_rx_wake" wakelock which is keeping the phone awake for hours at a time.
Could be, I do get a lot of wake locks sometimes but all it says for process is media server.... and searching on XDA and others. Nobody seems to know what causes that.
 
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Could be, I do get a lot of wake locks sometimes but all it says for process is media server.... and searching on XDA and others. Nobody seems to know what causes that.

Just a thought from a neophyte but if you're getting a lot of wake locks from a media server when on wifi could it be due to another dlna device on your network communicating with the s3 over wifi?
 
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Just a thought from a neophyte but if you're getting a lot of wake locks from a media server when on wifi could it be due to another dlna device on your network communicating with the s3 over wifi?
No idea, I only have the computers and printer and other devices (Fire etc) on the network. But even with them off it still occurs. I've searched high and low and tons of theories as to what causes media server wake lock on XDA but nobody knows how to fix it or what exactly causes it.
 
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