Loss of Data During Sustained Download

[zubbs1]

I recently started trying to use 4G LTE home internet. Here is all the raw specs:

Mofi 4500 V2 with the Sierra 7455 modem
ATT network
Tower - Band 2 (20MHZ), Band 4 (10MHZ), Band 12 (10MHZ), Band 30 (10MHZ) (according to band scanning on the mofi)

Generally get 45Mb/s down wireless and 65Mb/s down wired
My tower is ~0.5 miles line of sight from my house with a small treeline between, and I currently have no external antennas.

GSTATUS REPORT:

Code: Select all

AT!gstatus?
!GSTATUS:
Current Time:  159104           Temperature: 60
Reset Counter: 3                Mode:        ONLINE
System mode:   LTE              PS state:    Attached
LTE band:      B2               LTE bw:      20 MHz
LTE Rx chan:   1100             LTE Tx chan: 19100
LTE CA state:  INACTIVE                 LTE Scell band:B12
LTE Scell bw:10 MHz             LTE Scell chan:5110
EMM state:     Registered       Normal Service
RRC state:     RRC Connected
IMS reg state: No Srv

PCC RxM RSSI:  -52              RSRP (dBm):  -74
PCC RxD RSSI:  -58              RSRP (dBm):  -81
SCC RxM RSSI:  -51              RSRP (dBm):  -70
SCC RxD RSSI:  -48              RSRP (dBm):  -67
Tx Power:      --               TAC:         650C (25868)
RSRQ (dB):     -9.1             Cell ID:     053FED08 (88075528)
SINR (dB):     25.2

Now the questions:

1.) During sustained download activity (i.e. downloading a 100GB game from Steam) it will cruise along at maximum speed for some stretch of time, then nosedive to zero for up to 30 seconds, then return to full speed. The pattern stays the same for the entirety of the downloading.
My reseller emphatically swears there is no throttling or deprioritization on the sim (corporate hotspot account).
Does deprioritization equal zero data transmission, or just significantly less? I figured it would just go from like 40Mb/s to like 3 until the tower is less taxed and my rate would increase again.
Is this typical for 4G home internet, or is there possibly something with my setup? Is this a known issue that happens with the Mofi, the sierra 7455, or ATT?


2.) I know the Sierra 7455 can only carrier aggregate two bands. I found a detailed table outlining carrier aggregation possibilities that 2,4,12 and 30 can be aggregated together (caution- very large webpage table- I filtered for B2 as that appears to be my primary band) https://www.sqimway.com/lte_ca_band.php the tower nearest me does bands 2,3, and 12. Band 30 comes from another tower. Does carrier aggregation occur between more than one tower, or just on a single tower?

Is it realistic that I would see a noticeable increase in speed if I went the route of a DIY setup with a modem capable of 4 band carrier aggregation (or 3 if CA isn't between multiple towers)? Given my issues in question 1 above, is Quectel any better for the modem choice?

Sorry for the long post, I tried to be as thorough as possible. I appreciate any help you can give.

Cheers.

[gscheb]

Hello,
During this download are you using wifi or wired to Ethernet?

[zubbs1]

Hello,
During this download are you using wifi or wired to Ethernet?

I've seen the same pattern wired and wireless.

[gscheb]

ok,
So not just a wifi issue then. Are you doing other things with the internet while this is going on?

[Didneywhorl]

You can only connect to one tower at a time. Your modem may be able to do up to 7xCA but the tower setup and dynamic management determains how much you get.

Try a large download from somewhere else, like iTunes or something. See if the same issue occurs. You may be getting "managed" by the carrier network, or you may just be effected by oddities on Steams side.

Sierra makes a good modem, I prefer Quectels right now.

Upping to higher Category equipment and more antennas (4x mimo) MIGHT get you a better connection, but it might not. It will bring you current on equipment, the mofi base router and its modems are antiquated; though still useful up to around 90Mbps.

[terryjett]

I would expect this to happen with a 100GB file. Mobile networks are not designed to maintain steady connections and never were meant to download large files.. I experience the same thing even with 100MB files.

You may hear of others in larger cities not having the issue, but I personally have never had a steady download connection for large files. If it were mission critical for me to download a 100GB file, would ring up the carrier support and ask why downloads pause.

[BillA]

1.) During sustained download activity (i.e. downloading a 100GB game from Steam) it will cruise along at maximum speed for some stretch of time, then nosedive to zero for up to 30 seconds, then return to full speed. The pattern stays the same for the entirety of the downloading.

2.) I know the Sierra 7455 can only carrier aggregate two bands. I found a detailed table outlining carrier aggregation possibilities that 2,4,12 and 30 can be aggregated together (caution- very large webpage table- I filtered for B2 as that appears to be my primary band) https://www.sqimway.com/lte_ca_band.php the tower nearest me does bands 2,3, and 12. Band 30 comes from another tower. Does carrier aggregation occur between more than one tower, or just on a single tower?

Is it realistic that I would see a noticeable increase in speed if I went the route of a DIY setup with a modem capable of 4 band carrier aggregation (or 3 if CA isn't between multiple towers)? Given my issues in question 1 above, is Quectel any better for the modem choice?

Sorry for the long post, I tried to be as thorough as possible. I appreciate any help you can give.

Cheers.

1. I live in a larger city with great signal, and download 5-10GB files regularly but never see a pause.
I use a download manager (FDM - https://www.freedownloadmanager.org/) with the multi segment download feature turned on in order to speed up and max out my mobile connection (up to 200Mbps = 25MB/s). The difference is like night and day between Chrome's single segment downloading vs multi-segment mode.

2. Carrier aggregation could happen using the same or different towers, including the same or different bands (intra/inter bands), however there's nothing you can do to force CA (the tower is in control), other then locking your modem to a couple of active bands in your area. I prefer to leave the the modem on auto-scan in order to maximize the chances for CA even if the carrier changes bands/towers overnight (it could happen any time).

One of the best ways to get better speeds is by upgrading a higher CAT# modem, which usually also allows multiple CA's as high as 7, but again it's up to the tower to use it or not. A good antenna setup can help too.

Also, you may want to check to see if maybe someone else in your home is either streaming video or downloading something while your connection pauses/stops. Mobile data ain't the best for sharing multiple concurrent users.

[gscheb]

Ok,
My son uses steam and downloads file size 10 to 100 all the time. Use T-Mobile service.
When first started used mofi 4500 used to drop signal every 10 minutes or so doing these downloads.
Then we got rid of mofi and then used mc7455 with golden orb issue went away. Currently using Quectal EP06 and have no issues downloading files on steam.
While you have the Mofi I would try Throttling the download to half your speed abilities within steam.
Can do this under settings in steam.

[zubbs1]

Ok,
My son uses steam and downloads file size 10 to 100 all the time. Use T-Mobile service.
When first started used mofi 4500 used to drop signal every 10 minutes or so doing these downloads.
Then we got rid of mofi and then used mc7455 with golden orb issue went away. Currently using Quectal EP06 and have no issues downloading files on steam.
While you have the Mofi I would try Throttling the download to half your speed abilities within steam.
Can do this under settings in steam.

Just queued up a quick download and ran it at 24Mb/s limit. It took about 3-5 minutes, but it repeated the same pattern. I thought it was only at max bandwidth, but apparently not.

Sounds like I need to test out a new card/router setup.

I have a RT68U Router:



Is it possible to mount the modem to it using the USB input on the router, then flash golden orb onto it? This would at least save me the money on another router.

Cheers.

[terryjett]

1. I live in a larger city with great signal, and download 5-10GB files regularly but never see a pause.

Never had the luxury of great signal I guess. But then again have not lived in a large city in past 25 years. My life evolves around RSA (rural service area). Even with 80% signal, great stats constantly have varying speeds when downloading files.

Anyway, hope you get it figured out. Curiosity got the best of me, will be following

[Didneywhorl]

Yep, the RT-AC68U is on the list....

Ofmodemsandmen.com

[gscheb]

Right now my son is downloading a 200 GB file from blizzard. Been running 3.5 hours so far. While we doing other things with it as well.
Just letting you know since this is a bigger file. My signal isn't great either modem says like 58%.
Once again this is a Quectal EP06 on T-Mobile.

[BillA]

Right now my son is downloading a 200 GB file from blizzard. Been running 3.5 hours so far. While we doing other things with it as well.
Just letting you know since this is a bigger file. My signal isn't great either modem says like 58%.
Once again this is a Quectal EP06 on T-Mobile.

With mobile data there are lots of variables which come into play during downloads, including modem/router used, antennas, carrier, distance from tower, time of day/night, server load you're downloading from, etc. The only thing you can do is to insure you have the best possible signal/modem/antenna on your end, and pray to the mobile god for the rest.

[Adm1jtg]

Never had the luxury of great signal I guess. But then again have not lived in a large city in past 25 years. My life evolves around RSA (rural service area). Even with 80% signal, great stats constantly have varying speeds when downloading files.

Anyway, hope you get it figured out. Curiosity got the best of me, will be following

Also in rural area, lots of trees, cant even make a phone call without a booster and I see the same dips quite often even when running a simple speed test. I have frequently seen it jump to 30 and end on 8 all in the time of a speediest.

I am also using an EP06 but like i said my signal and all is far from ideal.

Also if you are using a mofi sim4 your already using a sierra 7455 so the above poster saying he/she updated to that modem and goldenorb and it having solved the issue... it had to be goldenorb not the modem that fixed things. If your mofi has carrier aggregation its a sim4.

Also maybe not directly in answer to your question but related, have you evaluated each band for signal strength and download speed and quality and tried locking down to the best you have? In my case a weaker signal with more quality worked far better then the strongest signal and of course left to its own my modem would always pick the strongest signal. Onve I found the best overall signal then I looked at the possible CA combinations for my modem and locked it down to the 2 bands that worked best together

[terryjett]

Pretty much got my issue solved. I always run he latest firmware for router and modem.

Once I replaced my power supply with a good 5 amp switching version, the issue seemed to disappear. While I was at it, drove a 12 ft grounding rod just outside and grounded all equipment to it. Have updated firmware in both router and modem since then and still solid as a rock.

Still have a few issues during peak summer, but nothing like before replacing my power supply.