Switching between 3G and HSDPA

I

Iam3G

Expert Member
Joined
Apr 9, 2007
Messages
2,317
Reaction score
0
Location
Cape Town
I know that 3G and HSDPA is built on the same infrastructure(meaning 3G and HSDPA is more or less the same thing), but at the same time its also 2 different networks our modems attaches to.

With the current software, we are able to control the switch between 3G/HSDPA to GPRS(and vice versa).

At the moment i'm happy with Vodacom's 3G/HSDPA, but theres a tiny insignificant issue i'm battling with. And i all i need some clarity as to if its at all possible.

I'm happy with the fact that i no longer experience any disconnections from the network and of the switch between 3G/HSDPA and GPRS, but my problem lies with the switch between 3G and HSDPA, and the switch between the 2.

IMO, its a disconnection within itself, especially concerning online gaming. My question is, is it at all possible to control the switch between 3G and HSDPA?
 
Iam3G said:
At the moment i'm happy with Vodacom's 3G/HSDPA, but theres a tiny insignificant issue i'm battling with. And i all i need some clarity as to if its at all possible.

I'm happy with the fact that i no longer experience any disconnections from the network and of the switch between 3G/HSDPA and GPRS, but my problem lies with the switch between 3G and HSDPA, and the switch between the 2.

IMO, its a disconnection within itself, especially concerning online gaming. My question is, is it at all possible to control the switch between 3G and HSDPA?
Click to expand...

3G and HSDPA use the same infrastructure. HSDPA uses a more efficient coding scheme to achieve faster speeds. If you modem detects the availability of HSDPA it will automatically use HSDPA. I think the entire Vodacom 3G network supports HSDPA (Vodacom3G can clarify this) so there is no need for your modem to switch to 3G.

WireFree
 
ABCD0018.jpg


Decent speed but *** latency.
 
WireFree said:
3G and HSDPA use the same infrastructure. HSDPA uses a more efficient coding scheme to achieve faster speeds. If you modem detects the availability of HSDPA it will automatically use HSDPA. I think the entire Vodacom 3G network supports HSDPA (Vodacom3G can clarify this) so there is no need for your modem to switch to 3G.

WireFree
Click to expand...

Correct.
 
Well i have this same effect, especially on MTN. The dash literally shows "3G" then goes to "HSDPA" , and continues to switche between them at times. Usually this switch comes along with lag-spike/delay [not necessarily a hard disconnect on the dash]. I only notice in places like online gaming where even a slight change in speed/whatever can cause the game to dc from the server etc....

So yea, while the theory is explained above, there seem to be a physical connection switch happening? This switch does something with the "stability" during the switch and that's the prob. In my MTN case i often see it bounce around as if it can't find HSDPA properly and falls back to 3G ....so i'm confused...

I think the entire Vodacom 3G network supports HSDPA (Vodacom3G can clarify this) so there is no need for your modem to switch to 3G.
Click to expand...

Ideally yes, but for some reason it still does pick up 3G ? Rather let me ask it this way:
Why is 3G picked up at all if there's HSDPA on the entire network? In fact why have it there?
 
Last edited:
diabolus said:
Well i have this same effect, especially on MTN. The dash literally shows "3G" then goes to "HSDPA" , and continues to switche between them at times. Usually this switch comes along with lag-spike/delay [not necessarily a hard disconnect on the dash]. I only notice in places like online gaming where even a slight change in speed/whatever can cause the game to dc from the server etc....
Click to expand...

Thats exactly what i'm experiencing. I immediately get disconnected from the game server. Or when i loading a page it just hangs, and i need to refresh a couple of times. This is what i meant by ot being a disconnection within itself.

diabolus said:
So yea, while the theory is explained above, there seem to be a physical connection switch happening? This switch does something with the "stability" during the switch and that's the prob. In my MTN case i often see it bounce around as if it can't find HSDPA properly and falls back to 3G ....so i'm confused...
Click to expand...

On the VMC/VMCLite Dashboard, after entering the PIN, if you leave it to initialize, it initializes to 3G. The modem's light blinks Blue. Once connected, the light switches to Cyan, and on the dashboard it displays 3G+. And while the connection is on, and you leave it idle it switches back to 3G(light goes back to blue, Dashboard displays 3G). Once you hit refresh on a page, light goes back to Cyan and Dashboard displays 3G+ again.

So there is infact a switch between 3G and HSDPA. So if there's a way to control the switch between GPRS and 3G, surely there should be a way to control the switch between 3G and HSDPA? Yes i know 3G and HSPDA uses the same infrastructure, but its still 2 different things, becoz you have one or the other.

If the software was developed in such a way to control GPRS and 3G, could such an option be added to control 3G and HSDPA?
 
Last edited:
GPRS/EDGE and 3G/HSDPA are two different networks, running at different frequencies, etc. So switching between the two is quite a process with hand-over, etc.

Switching between 3G-R99 and HSDPA is more a matter of jumping between different coding schemes (slightly more complex, but not much). Signal quality can do this for example.

What you might also be seeing is that the data card 'idles' in R99, i.e. when you're not transferring data, it will go into R99 but as soon as you start sending data it will switch into HS. This is basically to manage resources better.

You could try and run a background ping and see if it forces the card to stay in HS
 
vodacom3g said:
GPRS/EDGE and 3G/HSDPA are two different networks, running at different frequencies, etc. So switching between the two is quite a process with hand-over, etc.

Switching between 3G-R99 and HSDPA is more a matter of jumping between different coding schemes (slightly more complex, but not much). Signal quality can do this for example.

What you might also be seeing is that the data card 'idles' in R99, i.e. when you're not transferring data, it will go into R99 but as soon as you start sending data it will switch into HS. This is basically to manage resources better.

You could try and run a background ping and see if it forces the card to stay in HS
Click to expand...

Thanks. I understand it better now.

By running a ping in the background... i've logged onto a chat room where theres always data being transfered. Is that what you mean?
 
vodacom3g said:
Will also work if there is enough data flowing.

Typically you'll do a "ping -t *hostname*" in a DOS box.
Click to expand...

Tried the chat room thing, it didnt work either.

Isnt being logged onto the game server also a ping? Becoz theres always data being transfered while logged on.

and by hostname do you mean the game server? And doesnt the ping in the DOS box only last a few seconds?
 
The "-t" part of the command will make the ping run until you hit CTRL-C ;-)
 
You must log in or register to reply here.
Back
Top
Sign up to the MyBroadband newsletter
X