3G Switching to HSDPA and back

[colo]

In the past 3 weeks or so, my E220 card has suddenly started relentlessly switching between 3G and HSDPA. This causes lag in games, voice calls, etc as there is a 1-3 second gap during switching where data isn't transferred.

Does anyone know how to fix this?

 

[ginggs]

In the past 3 weeks or so, my E220 card has suddenly started relentlessly switching between 3G and HSDPA. This causes lag in games, voice calls, etc as there is a 1-3 second gap during switching where data isn't transferred.

I think the switching between 3G and HSDPA is a symptom of the gap in data transfer, rather than the other way round.

 

[colo]

It only really happens during continuous transfer - voice transfer and gaming. So I don't think that could be it.
It never used to happen, just started recently.

 

[MrOoze]

I'm experiencing the exact same thing - seems MTN have made a change to their network.. unless it's localised to a tower. Where are you located, Colo?

I play WoW, and have not been able to play on my MTN connection for about 3 weeks now, due to the switching between HSDPA and 3g. It seems to me MTN have heightened the threshold at which HSDPA will switch to 3g, but then, it switches right back - and each switch brings about 1 second of no throughput - making for a very spiky experience if your doing something with steady, low bandwidth usage - like gaming.

My same hardware with a Vodacom Sim in it works perfectly, so it's definately network related. I've had a brief look around the net to see if there's any "HSDPA Only" options around - no luck yet.

Plz change it back, MTN!

MrOoze

 

[colo]

Yeah its definitely the same thing we're experiencing.
Its happened to me in both Vanderbijlpark and Kimberley, so it must be a national thing - I doubt youre located there, MrOoze.

 

[colo]

Could someone with the divine power to change this (or to contact someone who can change this) please speak now...

 

[Grouter]

This happens to me all the time on vc's network, and at the moment i'm in australia on the optus network and it's doing it here while i'm trying to skype and it's driving me dilly. also an e220. skyping is almost impossible.

edit: I've moaned about this plenty in the vc section - it was good for a while, but the problems returned. I think it's definitely a network / tower equipment issue.

 

[AirWolf]

I haven't seen any dashboards that offer the option to stick to HSDPA.

When I'm having problems with switching between 3G and HSDPA, I normally use a continuous ping:

ping www.google.co.za -t

This does help most of the time to keep the connection on HSDPA.

Give it a shot, and post your results [good or bad] here.

 

[Grouter]

I haven't seen any dashboards that offer the option to stick to HSDPA.

When I'm having problems with switching between 3G and HSDPA, I normally use a continuous ping:

ping www.google.co.za -t

This does help most of the time to keep the connection on HSDPA.

Give it a shot, and post your results [good or bad] here.

Thanks for that, i remember a thread about it a while ago in the vc section. MyBB is dead slow at the moment from australia so i don't want to search for it just now.

Problem I had then with vodacom, and it is the same here out in australia, is that the continuous ping packet size, in order to keep the connection on hsdpa, must be so (relatively) large that it gets to be a significant data user itself. In other words, a ping of a couple of bytes seems unable to prevent switching back to 3g from hsdpa.

 

[ginggs]

When I'm having problems with switching between 3G and HSDPA, I normally use a continuous ping:

Problem I had then with vodacom, and it is the same here out in australia, is that the continuous ping packet size, in order to keep the connection on hsdpa, must be so (relatively) large that it gets to be a significant data user itself.

Is the 'switching' from HSDPA to 3G really a problem? As far as I know. the HSDPA, HSUPA and HSD+UPA reports from the modem just mean that data is being transferred on the faster protocol on top of 3G.
It's not like switching from the 3G network to the 2G network.

 

[MrOoze]

Is the 'switching' from HSDPA to 3G really a problem?

Well, if I can skip the sciences of networks, etc.. Every time my light on my E220 changes from Dark blue to Light blue or vice versa, there is about 1 second of 'lag'. This would not be a problem at all if it wasn't happening every 5 seconds or so.

Doing some ping tests, I find that running a "ping -t" to google will give me a nice steady ~350ms. If I refresh a page in IE, my light will change to Light Blue, and my ping will have 1 line at ~1500ms. For a few seconds (while the light remains Light Blue) my ping returns ~150ms. Then the switch back to Dark Blue gives another ~1500ms. And back to ~350ms.

This is the cycle that happens continuously when doing steady, low bandwidth activities. For me, anyway.

I reiterate that there is no problem on VC. And that this definately wasn't a problem about 4 weeks ago. So what's changed, and why?

MrOoze

 

[colo]

I tried the ping google -t, and it didn't help.
Whatever MTN recently changed on their towers, they better change back soon -_-

 

[MrOoze]

I tried the ping google -t, and it didn't help.

I have tried something similar to the ping idea. I downloaded a firefox mod which you can use to set a page to refresh automatically every xx seconds. I set it to 1 second and had a relatively smooth gaming experience.

Then I checked my usage... That's one workaround I shan't be trying again. Notwithstanding the fact that I shouldn't have to ping or trick the system into giving adequate service.

MrOoze

 

[vodacom3g]

I tried the ping google -t, and it didn't help.
Whatever MTN recently changed on their towers, they better change back soon -_-

The default Ping packet size might be too small to get the modem to switch into HS, up from R99.

Try and increase the packet size with the -l option, something like "ping -t -l 1024 and see what happens.

If it works, try and build a batch file that will do a big ping every so often, just enough to keep the modem in HS, but not every second.

BTW, from a network perspective, this is not good as you 'lock' resources other people on the tower might require, but then you gamers only live for latency and not being good neighbours.

 

[MrOoze]

The default Ping packet size might be too small to get the modem to switch into HS, up from R99.

Try and increase the packet size with the -l option, something like "ping -t -l 1024 and see what happens.

If it works, try and build a batch file that will do a big ping every so often, just enough to keep the modem in HS, but not every second.

BTW, from a network perspective, this is not good as you 'lock' resources other people on the tower might require, but then you gamers only live for latency and not being good neighbours.

I was actually just PMing you to take a look at this, V3G ... always 1 step ahead.

I'll try to get to some testing at lunchtime - see if I can find the ping threshold that will keep us in HSDPA. I suspect it's going to be quite the bundle-chewer.

May be more effective to find the minimum amount of time that the modem HAS to stay in HSDPA and just undershoot that. ie, if it's 5 seconds, run a single, great big ping every 4 seconds. I guess you were alluding to that.

I'll post back with anything I find.

MrOoze

 

[Grouter]

Notwithstanding the fact that I shouldn't have to ping or trick the system into giving adequate service.

+1 - a point I have made in the past too.

 

[vodacom3g]

+1 - a point I have made in the past too.

Remember, a wireless connection is substantially different than using fixed line solutions where you have a dedicated line per subscriber. On a wireless tower, you share the resources with all other users and there is a distinct limitation on these resources.

So the whole network is designed to give the best possible service, within these constraints, to everyone. Thus the network will switch you out of HS when you don't need high throughput and back again when you do.

For normal browsing, mail, etc. this should be pretty much transparent but obviously if you run latency sensitive applications (like gaming) you're going to notice the switch.

Not trying to push anyone away from using wireless )), but if you have a latency-sensitive application, fixed line will always be better. Just physics.

 

[MrOoze]

Remember, a wireless connection is substantially different than using fixed line solutions where you have a dedicated line per subscriber. On a wireless tower, you share the resources with all other users and there is a distinct limitation on these resources.

So the whole network is designed to give the best possible service, within these constraints, to everyone. Thus the network will switch you out of HS when you don't need high throughput and back again when you do.

For normal browsing, mail, etc. this should be pretty much transparent but obviously if you run latency sensitive applications (like gaming) you're going to notice the switch.

Not trying to push anyone away from using wireless )), but if you have a latency-sensitive application, fixed line will always be better. Just physics.

Absolutely understandable. It's just frustrating that it did work to suit our (gamers) needs, and now it doesn't. And Vodacom's trundling along fine. Are they planning to implement this change at VC?

I'm afraid I don't understand the benefit that switching to 3g faster offers MTN. Are they saving money somehow? Does this make a significant difference to network speeds of non-gamers? Perhaps you can shed some light, V3G.

MrOoze

 

[Grouter]

Not trying to push anyone away from using wireless )), but if you have a latency-sensitive application, fixed line will always be better.

I'll bet you didn't copy and paste that line from a VC ad

 

[vodacom3g]

Absolutely understandable. It's just frustrating that it did work to suit our (gamers) needs, and now it doesn't. And Vodacom's trundling along fine. Are they planning to implement this change at VC?

I'm afraid I don't understand the benefit that switching to 3g faster offers MTN. Are they saving money somehow? Does this make a significant difference to network speeds of non-gamers? Perhaps you can shed some light, V3G.

MrOoze

VC also works this way. It's inherent in the technology but it might be that VC switches faster so you won't notice as much.

Can't comment why MTN suddenly shows the slow switch, but won't be surprised if they rolled out new software and maybe a parameter got changed or something. Happens a lot, these networks are incredibly complex and to keep constant service levels over new software releases can be a challenge.

Just like in any other environment that requires constant software updates, i.e. anything with a CPU nowadays.