24 replies to this topic

[MECX]

MitchellO, on May 29 2007, 08:27, said:

Yeah standard 3G UMTS lets you be on a call and transferring data. Done it with a HTC Universal on UMTS.

Cheers for that :-)

Where abouts in the country are you>?

I suppose this is only a problem with HSDPA nodes then, unless anyone knows the standard way Normal 3G performs when transfering data and a call needs to be made--- It could drop to Circuit switched I suppose>?

[MitchellO]

MECX, on May 29 2007, 18:45, said:

Cheers for that :-)

Where abouts in the country are you>?

I suppose this is only a problem with HSDPA nodes then, unless anyone knows the standard way Normal 3G performs when transfering data and a call needs to be made--- It could drop to Circuit switched I suppose>?

Sydney Australia

[neilg]

thanks for the replies.  I am being served by HSDPA coverage eg: in HSDPA and connected as HSDPA rather than UMTS, but I am not 'in session' for data.  Eg no active PDP context.
As far as I am aware all voice call on 3G networks are still being connected as CS calls since it is the only way to get even 12Kbps voice QoS guarunteed.  ALthough the 3G/HSDPA networks do support IP Voice calls the network QoS so far cannot handle it so voice calls are still routed by good old fashioned CD.  (In fact I think quite a few of the networks are actually using higher rate CS for data traffic for certain services to guarantee QoS) - nice and bandwidth inefficient!

I'll keep tinkering and post back what I find!

[MECX]

neilg, on May 29 2007, 10:06, said:

thanks for the replies.  I am being served by HSDPA coverage eg: in HSDPA and connected as HSDPA rather than UMTS, but I am not 'in session' for data.  Eg no active PDP context.
As far as I am aware all voice call on 3G networks are still being connected as CS calls since it is the only way to get even 12Kbps voice QoS guarunteed.  ALthough the 3G/HSDPA networks do support IP Voice calls the network QoS so far cannot handle it so voice calls are still routed by good old fashioned CD.  (In fact I think quite a few of the networks are actually using higher rate CS for data traffic for certain services to guarantee QoS) - nice and bandwidth inefficient!

I'll keep tinkering and post back what I find!

Im sure the call traffic is packet switched in 3G as the operators are all moving towards fully IP CORE networks, they are infact using "Mobile soft switches" to change the Circuit swtiched data from the 2G mobile Phone to the base station to packet switched data to make a more efficient use of bandwidth accross the CORE networks.

3G is 100% packet swtiched from the phone to the Node, they may use the CS network to route to 2G nodes but im sure its packet swtiched from end to end for a 3G-3G call.

Interesting to hear comments im by no means an expert in this.

[neilg]

MECX, on May 29 2007, 10:36, said:

Im sure the call traffic is packet switched in 3G as the operators are all moving towards fully IP CORE networks, they are infact using "Mobile soft switches" to change the Circuit swtiched data from the 2G mobile Phone to the base station to packet switched data to make a more efficient use of bandwidth accross the CORE networks.

3G is 100% packet swtiched from the phone to the Node, they may use the CS network to route to 2G nodes but im sure its packet swtiched from end to end for a 3G-3G call.

Interesting to hear comments im by no means an expert in this.

:-) me neither and I guess we are going off topic :-)  Last I heard the IMS is only just now being rolled out with CSCF and media gateways etc.  Certainly most of the original 3G networks (with the exception of a few greenfileds) were rolled out with either enhancements to 2G MSC and xGSNs or a new 3G MSC and xGSNs with the RAN being all new (RNC and Node B rather than BSC and BTS in the 2G world).  Basically general status today is UMTS R99/R4 is most common, but that IMS core networks are gardually being dropped in - that said I am a little out of date these days as I tend to be involved in 'bolting on to' rather than providing network infrastructure outright, so maybe thinsg have moved on a bit quicker!