Different network conditions between prepaid sim and contract sim

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deweyzeph

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I'm experiencing really strange problems with a contract data sim card. I'm currently in the middle of the Karoo, got a Huawei B660 router attached to a LPDA 11Dbi antenna and up until yesterday the connection was rock solid. The router has got the farmer's contract data sim card in it. When I do a traceroute there is massive packet loss to any destination I do a traceroute to.

However, when I swop in my own personal prepaid sim card with a data bundle loaded on to it and do a traceroute to the exact same destination, the traceroute is flawless, no packet loss whatsoever and the connection works great.

How can it be possible that connecting to Vodacom with a contract sim card can have completely different network conditions to a prepaid sim card? And how can I fix this? It's the same router, same antenna, pointing to the same tower, just different sim cards.
 
Well, this is the Vodacom forum, and I mentioned my post that I'm connecting to Vodacom.
 
strange that you mention this. yesterday i was asking around the office if it's possible that a prepaid MTN SIM gets a stronger signal than a contract SIM. this because a phone with prepaid SIM at position A gets a stronger signal than contract SIM in a phone at position B. if i swap the phone positions the signal stays the same.

sorry to hijack :-)
 
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maumau said:
strange that you mention this. yesterday i was asking around the office if it's possible that a prepaid MTN SIM gets a stronger signal than a contract SIM. this because a phone with prepaid SIM at position A gets a stronger signal than contract SIM in a phone at position B. if i swap the phone positions the signal stays the same.
Click to expand...

The strange thing is that the signal strength is exactly the same when I swop sim cards (about -71 DBi), it just that the latency and packet loss increases exponentially when I connect using the contract sim card.
 
deweyzeph said:
I'm experiencing really strange problems with a contract data sim card. I'm currently in the middle of the Karoo, got a Huawei B660 router attached to a LPDA 11Dbi antenna and up until yesterday the connection was rock solid. The router has got the farmer's contract data sim card in it. When I do a traceroute there is massive packet loss to any destination I do a traceroute to.

However, when I swop in my own personal prepaid sim card with a data bundle loaded on to it and do a traceroute to the exact same destination, the traceroute is flawless, no packet loss whatsoever and the connection works great.

How can it be possible that connecting to Vodacom with a contract sim card can have completely different network conditions to a prepaid sim card? And how can I fix this? It's the same router, same antenna, pointing to the same tower, just different sim cards.
Click to expand...
What are your IP addresses when connected on the contract and prepaid SIMs?
 
ginggs said:
What are your IP addresses when connected on the contract and prepaid SIMs?
Click to expand...

I'm using the "internet" apn on both, and for both I am being assigned a private IP address in the 10.x.x.x range on WAN interface of the router.
 
Vodacom 4G is only enabled for post pay subscribers currently.
 
ginggs said:
What are your IP addresses when connected on the contract and prepaid SIMs?
Click to expand...

Sorry, just realised I made a mistake.

Looks like I'm being assigned a proper external IP address of 41.x.x.x on the prepaid sim card (the one that works flawlessly) and being assigned a private IP address of 10.x.x.x on the contract sim card (the one with high latency and packet loss).

Could this have something to do with it?
 
deweyzeph said:
What's that got to do with anything?
Click to expand...

Might have been a factor if you were in a 4G area. So obvious actually.

But after this post it's probably something else:

deweyzeph said:
Sorry, just realised I made a mistake.

Looks like I'm being assigned a proper external IP address of 41.x.x.x on the prepaid sim card (the one that works flawlessly) and being assigned a private IP address of 10.x.x.x on the contract sim card (the one with high latency and packet loss).

Could this have something to do with it?
Click to expand...

Would be funny if the contract sin didn't actually work and your pc/laptop was just using someone's wifi hence the internal range.
 
Qwikslver said:
Vodacom 4G is only enabled for post pay subscribers currently.
Click to expand...
O/T: Where have you been?
http://mybroadband.co.za/news/cellular/74042-vodacom-lte-for-prepaid-officially-launched.html

deweyzeph said:
Looks like I'm being assigned a proper external IP address of 41.x.x.x on the prepaid sim card (the one that works flawlessly) and being assigned a private IP address of 10.x.x.x on the contract sim card (the one with high latency and packet loss).

Could this have something to do with it?
Click to expand...
I'm sure it could.
 
Qwikslver said:
Might have been a factor if you were in a 4G area. So obvious actually.

But after this post it's probably something else:
Click to expand...

I'm at a client's farm in the Karoo, so there is definitely no "4G", by which I assume you mean LTE?

Qwikslver said:
Would be funny if the contract sin didn't actually work and your pc/laptop was just using someone's wifi hence the internal range.
Click to expand...

The private IP address is being assigned to the WAN port of the 3G router by Vodacom itself, there's no PC or laptop involved in this at all. Vodacom often assigns private ip addresses in the 10.x.x.x range instead of assigning a public IP address. Why, I don't know. It seems to happen pretty randomly whether you get a private or public IP address assigned to you when you make a connection.
 
jannievanzyl said:
Maybe try the unrestricted APN to see if it makes a difference.
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With the prepaid sim:

When using the "internet" apn, I sometimes get assigned an external 41.x.x.x address and sometimes a 10.x.x.x address

When using the "unrestricted apn" (which was provisioned), I always get assigned an external 41.x.x.x address.

With the contract sim:

When using the "internet" apn, I always get assigned a private 10.x.x.x address

When using the "unrestricted" apn (for which the contract sim has never been provisioned) I am able to make a connection, but I always get a private 10.x.x.x address assigned.

The problem with packet loss and high latency only occurs with either sim when a private 10.x.x.x address has been assigned.
 
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You have to provision the SIM for access to the unrestricted APN before it will work. It will give you a internet routeable address, which by the looks of things, should solve your problem. IIRC the unrestricted IPs fall in a 41.192.x.x range.
 
morkhans said:
You have to provision the SIM for access to the unrestricted APN before it will work. It will give you a internet routeable address, which by the looks of things, should solve your problem. IIRC the unrestricted IPs fall in a 41.192.x.x range.
Click to expand...

I don't want to use the unrestricted apn for this client though. They are on a contract sim, so I don't want any risk that the OOB shark is going to get them if there's some sort of DOS attack or anything else that may generate massive amounts of incoming traffic. The key question is why should there be such substantial packet loss on the "internet" apn in the first place?
 
deweyzeph said:
I don't want to use the unrestricted apn for this client though. They are on a contract sim, so I don't want any risk that the OOB shark is going to get them if there's some sort of DOS attack or anything else that may generate massive amounts of incoming traffic. The key question is why should there be such substantial packet loss on the "internet" apn in the first place?
Click to expand...

Jannie will have to answer that question, but I suspect it has something to do with the device doing the NAT/Firewalling. It's either overloaded or broken in some way.
 
morkhans said:
Jannie will have to answer that question, but I suspect it has something to do with the device doing the NAT/Firewalling. It's either overloaded or broken in some way.
Click to expand...

Jannie, would it help if I gave you the Cell ID of the tower the 3G router is connecting to?
 
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