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What is happening with 3G?
Frogis's profile

Tutor

 • 

3 Messages

Wed, May 14, 2014 5:06 AM

HELP - 3G light is flashing, microcell was previously working fine

Hello,

 

   I figured it was worth posting here so I have yet to have success with anything else. 

 

Background

 

I live in an area almost exactly inbetween three AT&T cell phone towers, so subsequently my phone is constantly switching singnals from one tower to the other giving me very inconsistent service.  After diagnosing the problem with AT&T about six months ago they sent me a micro cell free of charge, and it worked absolutely fantastic until....

 

The Problem

 

About a week ago my microcell's 3g light started flashing, this had happened once or twice before so I performed a simple reset but it did not fix the problem like before.

 

  •   I tried resetting my modem, router, and microcell
  •   hard resetting my microcell for 30 seconds
  •   de-activing and re-activating my microcell twice
  •   checking my power cord to make sure it was the right voltage
  •   getting a replacement microcell sent to my house
  •   setting up my microcell in the alternate arrangement (modem-->microcell-->router)
  •   updating the firmware on my router

and none of these fixed the problems.

 

My current internet is about 30mbps DL and 10mbps upload so that isn't the problem

The ports on my router are all opened, and nothing has changed to effect that

 

After going extensively through the forums I am kind of at a loss of what to try next.  Any suggestions from people on the forums?

 

I am currently located in the East Bay of California (Alameda, CA)

 

Thanks very much.

 

-Frogis

 

 

OttoPylot

ACE - Expert

 • 

19.2K Messages

8 years ago

That's good. VDSL, which is a combination of fiber and copper, has some of the same issues as copper-only lines but can be less tolerant of line faults like bridge taps etc so it has to be carefully installed and maintained.

Avedis53

Professor

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2.2K Messages

8 years ago

If you are behind a "jury rigged" (old nautical term BTW as opposed to "jerry built") network at work, I'm not surprised you see a wide variablity in VOIP metrics.  I wouldn't draw any conclusions by what you see at work, even if they are with the same ISP.

 

Just to make sure I'm understanding your current status:

 

  Have you still had only one instance of the Mcell going to a flashing 3G light that cleared when you power cycled your Mcell?

 

I know you've mentioned that you have had your phone beep 3 times and then drop a call 4 times while connected to the Mcell.  Is this still happening?

 

I asked previously about voice quality during your phone conversations.  Robotic?  Cutting out? Fuzzy?  Have you noticed any of this?

 

I know you've mentioned that others nearby have experienced the same problem.  Otto's comment about a Service Area problem may be pertinent.

 

You said your ISP has switched you from interleaving to fast buffer.  Interleaving is an error correction protocol that is implemented for your line at the DSLAM. With interleaving enabled, the DSLAM can correct errors in the data stream it receives before passing that data to your gateway router.

 

It is usually implemented on noisy or marginal lines and can greatly increase sync stability and effectively eliminate "first hop" packet loss. The largest drawback to interleaving is that it will increase your ping time, specifically to your first hop gateway router.

If interleaving is not enabled on your line, it is configured as FastPath (fast buffer). FastPath allows the DSLAM to pass the data received from you to the first hop router without performing any error correction. As a result, marginal lines could experience an increase in packet loss and decrease in sync stability (i.e. frequent sync loss). However, FastPath has lower ping times, especially to the first hop router.

 

I question whether this change will help you and might hurt you.  I guess you will find out and your ISP can always switch back to interleave if it does muck things up.

 

Please provide answers to my listed questions so I am current on your problem.

 

 

guitargain

Scholar

 • 

187 Messages

8 years ago


@Avedis53 wrote:

If you are behind a "jury rigged" (old nautical term BTW as opposed to "jerry built") network at work, I'm not surprised you see a wide variablity in VOIP metrics.  I wouldn't draw any conclusions by what you see at work, even if they are with the same ISP.

 

Makes sense

 

Just to make sure I'm understanding your current status:

 

  Have you still had only one instance of the Mcell going to a flashing 3G light that cleared when you power cycled your Mcell?

 

Yes that is correct

 

I know you've mentioned that you have had your phone beep 3 times and then drop a call 4 times while connected to the Mcell.  Is this still happening?

 

Not since it happened the 4 times I mentioned

 

I asked previously about voice quality during your phone conversations.  Robotic?  Cutting out? Fuzzy?  Have you noticed any of this?

 

The voice quality seems to be fine as it always was with a little garbling or echo every once in a while.  Haven't used it enough to say the new mc is better or worse but doesn't seem to worse in the instances I have used it.  I do sometimes get an echo when talking to my wife when she is on MC and I am away but I get that from time to time calling other cell phones too so that's probably nothing to do with MC.

 

I know you've mentioned that others nearby have experienced the same problem.  Otto's comment about a Service Area problem may be pertinent.

 

You said your ISP has switched you from interleaving to fast buffer.  Interleaving is an error correction protocol that is implemented for your line at the DSLAM. With interleaving enabled, the DSLAM can correct errors in the data stream it receives before passing that data to your gateway router.

 

It is usually implemented on noisy or marginal lines and can greatly increase sync stability and effectively eliminate "first hop" packet loss. The largest drawback to interleaving is that it will increase your ping time, specifically to your first hop gateway router.

If interleaving is not enabled on your line, it is configured as FastPath (fast buffer). FastPath allows the DSLAM to pass the data received from you to the first hop router without performing any error correction. As a result, marginal lines could experience an increase in packet loss and decrease in sync stability (i.e. frequent sync loss). However, FastPath has lower ping times, especially to the first hop router.

 

I question whether this change will help you and might hurt you.  I guess you will find out and your ISP can always switch back to interleave if it does muck things up.

 

That's the cool thing about having a friend at the telephone company he can switch it back without me having to involve the office. He told me he wanted me to do all the ping tests and speedtests and voip tests with it this way and see what happens which i can't do until I get home tomorrow morning.  Gotta answer 911 calls on the ambulance til then.:)

 

Please provide answers to my listed questions so I am current on your problem.

 

 


 

OkieSaytar

Mentor

 • 

51 Messages

8 years ago

Looking at my DHCP lease's I set a static one IP for MCell.

 

When Powered up it sets another IP......10.x.x.x ......(the IPSec Tunnel I assume)..so in effect My MCell has 2 IPs.

One I give it.............and the one the IPSec in the MCell sets up.

 

I don't think it makes any difference......this was done on the just received (3rd one) Replacement.

 

Did not observe this behavior on the other two previous Mcells.

 

If left on dynamic dhcp it only gets the one 10.x.x.x.....................go figure.

OttoPylot

ACE - Expert

 • 

19.2K Messages

8 years ago

Something is wrong with your setup then. The MicroCell cannot assign it's own IP address. There is a hard-coded UDP address and iptables used to do NAT as well as udhcpd to handle the dhcp-server duties but that is not configurable or accessible to the enduser (at least not easily). The protocols are built-in to the SoC chips and are the same across all the model/version lines.

OkieSaytar

Mentor

 • 

51 Messages

8 years ago

Exactly.....it ask for it's own DHCP address and presents its internal mac # when it creates the tunnel ......if the customer's DHCP server is on and working it will get an address.

 

EDIT: All routers (of which MCell is) have more that no MAC...The external WAN address and Internal Address.

 

I didn't configure anything......the DHCP server and the MicroCell did their own dance.

 

You reading that into what I said yourself....I was just commenting on what I had. I know it is all Hard Coded in the MCell.....and if it ask the DHCP server will give...........simple.

 

You can't PROBE the address for packets or whatever as its a Tunnel, but you can see the IP the MCell creates.

 

If I could post a screen shot of my DHCP page it would show the device IP, MAC and manufacturer ID (1st - 3 pair's of mac address).

 

Also you can check this link out    Gibson Research......if your interested....it is to Steve Gibson Research.....he's been creating PC utilities as long or longer than Peter Norton did before he sold out to Symantec, and his research is well known.I used alot of his security and PC utilities back in the DOS and Early Windows (3.11) days. Take that for what you think its worth.

 

It is a port scanner that probes for ports and does a little deeper analysis and can show open, closed AND "Stealth Ports" those open but configured not to respond to normal pings for security reasons, like some of the so called port scanner sites.

 

Every "tech" I have talked with sends you to yougotsignal, ipchicken, etc........these sites will not show or report back on open, stealthed ports.Most of those sites will try to charge you for anything that will do more.....

 

Stealthed ports are OPEN and work as designed.....but as I have discussed before they don't respond for network security reasons. He explains it on the site.

 

I will be passing my information and scans on up to Engineering. For whatever good it will do, which has been little so far. The real interest seems to be lacking.

 

 

Chow.

 

OttoPylot

ACE - Expert

 • 

19.2K Messages

8 years ago

You are free to do what you want. If you would like to pm me with whatever further information you get I'd be happy to pass that along to the Admins. I have sent them links to some of your other technical posts. However, posting that here will serve no purpose to the novices who come here for help other than confuse them.

Avedis53

Professor

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2.2K Messages

8 years ago

@ guitargain - Report back when you have more history with your current Mcell.

Avedis53

Professor

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2.2K Messages

8 years ago

For God's sake Otto.....get the admins to fix this PM problem.  I can't create new PMs or reply to PMs with Firefox.  I have to switch to IE to send PMs.

Avedis53

Professor

 • 

2.2K Messages

8 years ago

Forget PMs....I can't send or reply with IE either now.

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