02-18-2013 8:49 AM
While I didn't encounter this problem initially when I started up my Mcell a few months ago, it has now become a daily ritual that I hope someone here can help me with.
Motorola SB 6120 modem -> Netgear WNR3500L router -> Mcell
The Mcell is connected to the router with a pair of Netgear Powerline 200 Nano Adapters because my modem and router are located in the basement with no exposure to window for the Mcell to see a GPS satellite. The connection is good.
My Charter ISP connection is 30 mbps down and 4 mbps and is rock solid.
What's happening and what I've done so far:
Usually once a day I will no longer see the AT&T Mcell indication at the top of my iPhone 5. When I check my wife's iPhone 4S she has also lost the AT&T Mcell indication.
Turning the phones off and then on does not bring back the Mcell connection. Switching Airplane Mode off and then on does not bring back the Mcell connection.
The Mcell has all solid green lights when I go to check it after seeing the lost connection. If I power cycle the Mcell, the phones will then show an Mcell connection again until the next time they lose the connection which is usually once/day but not at any particular time.
I have the latest firmware on all devices.
When I check my router's admin page after a lost connection, the router indicates that the Mcell's IP address has not changed and it remains the same after power cycling the Mcell.
On the WAN page for my router, I have set the MTU size to 1492 and set the NAT Filtering to "Open" instead of "Secured". No improvement after doing so.
Suspicious of the Powerline Adapters, I tried disconnecting and reconnecting the Ethernet cable from the Mcell to the Powerline Adapter to mimic a temporary loss of connection to the router to see if that affected the Mcell connection. The Mcell connection was not lost.
I have not set any open ports or a static IP address for the Mcell yet. Is what I'm experiencing indicative of this solution? Does anyone have any other thoughts as to what try next?
I don't want to waste my time with an AT&T Level 1 tech support person because their suggestions are almost always worthless. I have better luck contacting user forums and that is why I'm posting here.
Thank God I was able to convince AT&T to give me a Mcell for free because if I paid $200 for it, I'd be very upset right now.
Thanks In Advance!
02-18-2013 12:57 PM
If I understand your setup, you do not have the MicroCell near a window and you are not using an external GPS antenna cable. Is that correct? Is the GPS light a solid green? The MicroCell MUST have constant GPS lock for it to work properly, not just during the initial activation. Powerline Adapters work well for a lot of applications but I don't know how well they work with MicroCells. In theory, they should be fine but the MicroCell is finicky so that may be an issue as well. But at the very least, you need to maintain a GPS lock at all times.
02-18-2013 2:39 PM
The Mcell is on another floor with a window view. That is why I'm using Powerline adapters as my house in not wired for Ethernet. I have a solid green GPS light and when I measure the GPS signal using an iPhone app at the Mcell's current location, I get good signal strength.
As I stated, I can unplug the Powerline adapter's Ethernet cable and plug it back in again and the Mcell does not drop out so I do not believe the Powerline adapter is the cause of the problem.
Any other thoughts?
- edited 02-18-2013 3:17 PM
Ok. If all lights (ethernet, GPS, 3G) are not blinking green or red then you should be solid with the MicroCell and it's the iPhone's communicating with the MicroCell or vice versa. You can try resetting the iPhone's network settings but make sure you have settings written down because you may lose them (passwords, etc) and have to re-enter them. If that doesn't work, try priority setup. Modem -> MicroCell -> router. That takes the router and its settings out of the chain. Some folks prefer that connection. Powerline adapters are really cool but they are subject to line noise and if your line has become noisier for some reason, maybe.......
02-18-2013 4:39 PM
I really don't think it is an iPhone issue for two reasons. First, I lose the Mcell connection to both iPhones at the same time. Second, when I power cycle the Mcell, both iPhones automatically reconnect and indicate "AT&T M-Cell" at the top of the display. It might be a faulty Mcell but I don't know.
I read back in this thread somewhere about tower signal strength competing with the Mcell signal for your phone's attention. How does that work?
The Powerline adapters have indicators to show the communication speed and mine are always in the green which means it is approaching 200 mbps. I can't vouch for any noise though. However, I can't think of a worse-case scenario than completely losing the Ethernet connection and re-establishing it again which I can do numerous times by unplugging the cable and the Mcell keeps right on working and the iPhone show no loss of connection when I do that.
My hunch is that the Mcell is losing connection with the AT&T servers because of the router interfering with the communications somehow. Do you think I should mess around with a static IP or port-forwarding? I've power cycled the router and the Mcell and the IP address doesn't change.
I guess my next troubleshooting steps are to eliminate the Powerline adapters as a cause by moving the Mcell next to the router and hardwiring it to the router.
If that doesn't work, then I can try the priority setup. The problem is that doing either of these steps requires moving the Mcell to a location that doesn't have line-of-sight, window access for the GPS. I've read in other forums that once you establish a GPS signal (steady green light), if you quickly unplug the Mcell and move it to another location in your house, it will retain the GPS location even though the Mcell can't "see" the GPS satellites. I don't know if this is really true though.
The whole point of the Mcell was to permit me to use our iPhones anywhere in the house (four floors). I live in an area that is far enough away from the nearest cell tower that on the bottom two floors of my house I get one or no bars of signal strength. I can get two or three bars on the top two floors though.
02-18-2013 9:32 PM
Ok. Lots of info. 200Mbps is just the line speed and doesn't really have a direct bearing to the speed that your phones are getting. My iPhone 5 will connect to LTE (outside of MicroCell range) at around 30Mbps but in-home, on the MicroCell, the iPnone speed is about 2-3Mbps, but the difference in phone response is minimal (see my post on the MicroCell and iPhone 5 Speed Test).
There are some issues surfacing with iPhone 4 and the iOS 6.1.1 update that is affecting some phones maintaining 3G connections. Hard to say if this is your issue or not. Apple is aware of it.
Everytime the MicroCell is rebooted, it establishes a connection to the closest tower and adjusts its transmission output according to the detected tower output. That can vary from time to time depending on many factors so re-booting the MicroCell often may affect MicroCell transmission strength. The difference should be negligible but re-booting the MicroCell should be kept to a minimum.
Moving the MicroCell quickly from one location with good GPS lock to an area with no GPS lock may work but it is no guranatee because the unit needs to maintain GPS lock at all times. If it works, great. But if it doesn't work, you haven't really proven anything.
I use port forwarding for my MicroCell because that has given me the most reliable and robust connection under any circumstances. One shouldn't have to do port forwarding because it should just be plug and play but in my case, and others, this was the best solution for me.
If you are really far away from a tower then that can be an issue because you still need to have a tower to connect to. If you are only getting 2-3 bars on the top floor and no bars on the bottom floor then you may want to change the location of your MicroCell. Put it on the top floor where the tower signal is the strongest and that may be enough to give you reliable connectivity on the bottom floors.
02-19-2013 12:20 PM
I understand that 200 Mbps is the maximum rating for the adapters. Interestingly enough, AT&T recommends Powerline adapters in their Mcell User's Guide and sells them on their website for applications such as mine.
I do not have LTE service at my location so my iPhone 5 uses 4G here. When I use Speedtest.net's Mobile app on my iPhone 5, I get 32.17 Mbps down and 6.33 Mbps up with 54 ms ping using WiFi. That is slightly under my computer's hard-wired Ethernet connection results and the purchased service from Charter.
Switching to 4G, I get 5.58 Mbps down and 1.54 Mbps up with 209 ms ping. That's through the Mcell and showing 5 bars and that's 2 floors down from the Mcell. Can't really complain about that all things considered.
Last night, I saw that both iPhone's connection to the Mcell had dropped and the 3G light was flashing green on the Mcell. That's is not what I had been usually seeing, which is a lost connection on both iPhones and a steady green light on the Mcell. After several minutes both iPhones automatically reconnected to the Mcell. The User's Manual states that a flashing green 3G light means that the Mcell may be activating or downloading new software. Since the iPhones automatically reconnected to the Mcell, I assumed that there was new software being downloaded. I don't know how often AT&T updates their software for the Mcell.
Sometime later during the night, the usual connection loss occurred again for both iPhones and in the morning I had to reboot the Mcell to establish a connection. I also noticed that the IP address to the router had changed.
Your explanation of the Mcell's adjustment of output depending on the nearest tower's signal strength is very interesting. I'll investigate Mcell locations after I see if setting a static IP address for the Mcell and opening ports 123 through 4500 for that address helps the problem.
- edited 02-19-2013 1:07 PM
It's been a long time since I looked at the Users Guide so I wasn't aware of the recommendation for PowerAdpaters. That's a bit surprising given that line condtions, installation, age of house, etc all can affect how well PowerAdapters work.
If the 3G was blinking green then communication between AT&T and the MicroCell was lost. That usually happens after an update while the MicroCell is going thru the update process but AT&T usually does their updates in the middle of the night so as to not interfere with the phone if in use.
If the IP address to the router changed that could explain some of your issues. Is your connection cable or DSL (static or PPoE) and do you have a static IP address from Charter? Port forwarding to a static assigned IP address for the MicroCell might correct your issues. That way, even if your router address changes, the address of the MicroCell doesn't, and if you base that static IP address on the MAC address of the MicroCell, you're assured of a connection, as long as the MAC address is detected. If the line conditions are fluctuating (for whatever reason), and the router is trying to detect connected devices, that may be confusing the MicroCell and your phones so they start looking for a signal, can't find one to lock on to, and disconnect. The MicroCell Troubleshooting Guide at the link in my sig has the correct protocols for the ports you need to forward, etc.
02-19-2013 3:50 PM
I'm on the west coast and it was about 10 PM when I noticed the blinking 3G light so maybe AT&T thinks that's late enough...who knows?
I have a cable modem and Charter has dynamic IP addressing for residential customers. Since my Mcell is behind the router, I have set a static IP address for the Mcell based on its MAC address and forwarded the proper ports as per the instructions.
I'll post back with results.
FYI, If you haven't read this article at Anandtech about the Mcell, it is very informative but somewhat technical.
02-19-2013 4:00 PM
In addendum, I think some of my trouble is due to the number of devices I have connected to my network. Last count shows 12 including a repeater so I can get WiFi coverage throughout my house. As devices are dropping on or off my network, IP addresses are getting shuffled around in the router.
Also, the iPhones' WiFi will bounce between the router and the repeater depending on where we are in the house since they automatically switch to the stronger signal of the repeater on the upper floors when the basement-located router gets out of range. I don't think that affects the Mcell though.
02-19-2013 8:25 PM
I've read that article from Anandtech. It is old but the basic information is still somewhat sound. If your LAN is as complicated as you say then that could be your problem. Too many conflicting signals.
02-21-2013 3:22 PM
It started out looking promising. I went a day without the iPhones losing a connection to the Mcell but it happened again late last night and again this morning. So the static IP address and port-forwarding changes don't appear to have helped any.
Next step I'm taking is to drop everything off the network except my two computers and the iPhones and see if that makes any difference. If so, then I'll add network equipment back one at a time to see if there is a singular offender. Perhaps my repeater is causing the problem.
If that doesn't help, then I'll try the alternate installation with the Mcell in front of the router which is located in my basement. I'll use a couple of long Ethernet cables and temporarily locate the Mcell by a window to establish a GPS lock and then move the Mcell to where I'd like to have it. Hopefully it will be satisfied with the GPS signal lock long enough to see if the alternate installation makes a difference. If that works in fooling the Mcell and it eliminates the lost connections then fine. If I eventually lose GPS lock then I'll look at getting an external GPS antenna if the alternate installation works.
I don't really like this solution because I'd rather have the Mcell centrally located in the house to cover all floors but if it just covers the lower two floors where my cell phones drop off the tower and I have to go through a switchover to the tower on the upper two floors then I guess that's what has to be.
02-21-2013 3:33 PM
One other question. I've seen it recommended in this forum that one do a network reset on the iPhones to help establish a connection with the Mcell. How can that work? The iPhones communicate with the Mcell using the cell phone's cell transceiver , not the WiFi transceiver.
- edited 02-21-2013 7:52 PM
I just read the setup instructions today to answer another question and the docs do say to not put the MicroCell in the basement so that's a consideration.
Resetting the iPhone has worked for some. Technically I'm not sure why but it may have something to do with the way the signal is recognized and configured (on the phone). It can't hurt anything. Just make sure you have your network setting written down in case the phone's settings go to default. I keep my WiFi on all of the time with my iPhone and there is no problem with the MicroCell.
Please remember that the GPS signal needs to be maintained at all times so you need to figure out how to keep that setup (either in front of a window or with an extension antenna that is is contact with the sky).
03-01-2013 9:12 AM
Ok....so I tried removing everything connected to my router except the Mcell and I still lose the connection to our iPhones. I then tried connecting the Mcell directly to my modem first and running the output to my router (alternative connection). Again, I lose the connection to my iPhones at night (only thing consistent about this is that the lost connections always occur at night while we are asleep). I tried deactivating and then reactivating the Mcell while using the alternative connection and I still get the same result. I tried a hard reset while using the alternative connection and I still get the same result.
One thing I noticed while using the alternative connection is that the packet loss my router sees has gone up alarmingly. I am a participant in the SamKnows ISP database where my router communicates on a hourly basis with SamKnows servers to measure connection quality parameters (downstream speeds, upstream speeds, lag, packet loss, jitter....etc). This information is used to measure the quality of the services provided by ISPs and is reported to the FCC. I don't believe this is having any effect on the Mcell as the router is downstream of the the Mcell.
At any rate, I've tried everything I can think of except replacing the Mcell and that will be the next step. If the new Mcell does the same thing, then my next solution will be to install a digital AC timer that will automatically power cycle the Mcell early every morning as a power cycle is the only way to re-establish a connection to my iPhones.
Now, off to the sad land of AT&T customer support to convince these clowns to replace my Mcell......