Slow 3G connection

Hi all,
I’ve a Huawei 3G usb modem (K3765) used within a Huawei D100 WiFi modem.
With this conf I’ve an average throughput (speed) of 2.5 / 3 Mpbs.
Now, using the same modem with a Mikrotik RB751G-2HnD, the maximum speed is 0.7 - 0.8 Mbps.
What’s the problem ?
Are there default parameters to modify ?
Thanks.
Nicola.

I can’t answer your question, but I have a ZTE-MF821(4G/LTE) USB modem plugged into a RB751G-2HnD.

Plugged into my laptop I get a down/up speed of 60mbps/20mbps
Via the RB751 I get a down/up speed of 12mbps/3mbps

I thought it might have just been the CPU on the RB751 not keeping up, but when downloading at full speed it sits at about 3%, so I do not think that is the issue.

So if anyone has any ideas there are now two people interested in the answer

compare pings between the two setups while downloading one single file

For anyone else coming across this; the answer to the speed difference between when you have your 4G USB modem plugged into a laptop and when you run it through a Mikrotik is related to the PPP session.

If you have a USB 3G/4G modem that requires PPP to connect then you speeds will suffer if the mdoem is plugged into the mmikrotik. If you can find a modem that detects as an LTE interface AND your carrier will simply issue an IP Address if you have the correct APN then this is a better way to go.

We have found that the best way to go is to use a third party modem such as the Dovado Tiny to handle the 3/4G leaving the mikrotik to do what it does best. The Dovado (and I assume that there are others out there) supports a wide range of modems in bridge mode so the WAN interface of the mikrotik still has your public IP.

Andy

So the same device does not have a ppp/dial-up connection when used with Windows laptop ? Or it does ?

On the windows laptop it uses a connection manager supplied by the carrier (in this case Telstra Australia) that does not use PPP

This post in an australian broadband forum implies that there is some kind of 25mbps limit for PPP in the mikrotik http://whrl.pl/RdyXWC

Interesting. Has it been confirmed by the Mikrotik and does they plan to improve it?

I have not sent anything into support, or had any confirmation from them. I think they have bigger issues at the moment with all the serious problems that need fixing in v6.x. Over time though I think it would be a natural progression to improve the LTE support.

If this is an issue close to your heart though, don’t let me stop you from submitting something.

My correspondence with the MT support didn’t reveal any technical details or reasons why it is so, but they confirmed that PPP has speed issues: “when you will run a speedtest you will not get higher speeds that 25mbps on 4g, that is all.”. The 3G should be unaffected by it.

Thanks. Now we know for sure.

Though in the real world I have never got about about 12mbps with ppp over 3/4G