CSL highlights potential of LTE roaming

Seen in the exhibition hall at this week’s Mobile Asia Congress event: CSL’s LTE roaming demo/trial with parent company Telstra, which showcased the benefits of local breakout for LTE roamers.

The trial utilized Telstra’s GRX to transport Diameter signaling between the two networks. Telstra roaming customers tested services on CSL’s LTE network including HD multi-party video conferencing, video streaming and data speed benchmarking against existing 3G roaming.
 
One key result that differentiates LTE roaming from 3G roaming: getting the same throughput speeds as local users thanks to LTE’s local breakout capability that allows data traffic to be offloaded to the roaming network rather than routed all the way back to the home network first.
 
“With 3G, there is no local breakout because operators want the traffic sent back home to them so that they can charge for it,” CSL chief technology officer Christian Daigneault tells telecomasia.net. “LTE brings signaling into the picture, so you can still charge for data even with local breakout.”
 
The end result is getting similar throughput speeds as local users, which also means improved latency by up top 90% compared to 3G. “So we’re showing that local breakout makes a big difference,” Daigneault says.
 
LTE operators will also have the option of offering users home routing for suitable apps like exclusive home operator services and corporate VPNs.
 
Daigneault cautions that the demo is just that – a demo, not a finished product available for Telstra or CSL customers. “There are still some things that haven’t been resolved yet, like just how to do signaling,” he says. “If you do it one-to-one like we’re doing with Telstra, it’s simple. We’re just showing that it can be done and the benefits you get, such as better latency.”
 
Meanwhile, CSL – along with its equipment supplier ZTE – also demonstrated CS Fallback technology as its initial voice solution for LTE.
 
“The first LTE smartphones will be coming early next year, so we wanted to showcase the capabilities of CS Fallback for voice,” Daigneault says, adding that the results have been good.
 
“The big challenge with CS Fallback has been that some vendors think it will slow down call-set-up times significantly, but we’ve seen no real impact,” Daigneault says, though he admits the technology adds a couple of seconds to call set-up. “But users aren’t really going to notice the difference unless they use a stopwatch when they make a call.”
 
Daigneault also said CSL’s use of CS Fallback early on won’t prevent it from adopting VoLTE – the GSMA-supported voice solution for LTE – in the future.