Optimize Audio Performance

Flawless audio under all conditions

Consumer electronics firm characterizes and defines product performance — cuts development and technical support time by 80%.

“The IWL Network Emulator helped us emulate the most probable real-world customer usage scenarios in the lab, so that we could learn how our product would perform under both extreme and routine network conditions. This meant that we could cover all required usage scenarios, provide clear information on product performance to our sales channels, pinpoint issues and problems before they arose.”

— Lead Engineer

Company profile

The Company’s flagship product: a music player that plays audio from streaming music services, internet radio stations, and podcasts.

The concept: combine powerful technology and simple, natural controls to make every day moments joyful.

Challenge: Seamless, trouble free operation

For a successful product launch, the music player must accommodate every possible consumer usage scenario, including all the limitations and issues with home Wi-Fi networks and last mile connectivity.

The music player operates in home Wi-Fi environments. These environments manifest a plethora of problems:

Insufficient Wi-Fi range and power
Under-provisioned Wi-Fi (too many users; too heavy a load)
Radio interference
Device driver upgrade and incompatibility issues
Interference from other Wi-Fi access points, especially in urban areas

These environmental conditions cause packet loss, delay, duplication, jitter, and re-ordering, potentially wreaking havoc on the audio experience.

Emulating home Wi-Fi scenarios

Testing began with IWL’s home network scenarios. Then, more custom scenarios were included for home Wi-Fi to evaluate music player performance under a wide range of conditions. These included latency, limited bandwidth, and packet drops to emulate an overloaded wireless network.

A scenario with 5% packet loss and latency around 150 ms.
An upload bandwidth restriction of 128 Kbps and a download restriction of 1.5 Mbps.
A scenario combining (1) and (2).

Emulating the carrying of music players around the home

One use case: mobile music players. Customers carry the music player around their house while streaming live music. Lab testing required only a single wireless access point connected to the IWL network emulator as a means to route traffic through it. Then, applying custom time-varying impairments:

Random switching between two paths, A and B, with a 5% chance of a switch every second.
- Path A (Wi-Fi inside your house) has 0% packet loss, 80ms latency, upload rate of 512 kbps and download rate of 1.5 Mbps.
- Path B (Wi-Fi on your patio) has 2% packet loss, 120ms latency, upload rate of 512 kbps and download rate of 1.5 Mbps.
A scenario that mimicked evolving bandwidth as a device moves about your house.
- Normal base rates of bandwidth and latency.
- Time 0 to 60 secs has the normal base values.
- Time 60 to 120 secs steadily slides the rates down to 25% of the base rates, increases packet loss to 3%, and increases latency to 150 ms.

The IWL network emulator’s time varying impairment GUI controls and support for multiple, concurrent network flows to target specific packets and protocols made it possible to perform the desired custom scenarios. Additionally, impairment statistics gathered from live networks were also used in scripts that controlled the time-varying impairments in the lab, allowing automated testing.

Complete operational transparency saved money

Because the electronics company knew how the music player would perform under real-world home networking conditions, the designers could provide sensing and detecting code to dynamically adjust the customer's music experience. The music player can reliably detect when the Wi-Fi is overloaded, turned off, etc. to eliminate negative user experiences and user frustration.

The electronics company estimates that the music player’s enhanced functionality has eliminated about 80% of network related development and testing time.

"By using the IWL network emulator to customize a comprehensive portfolio of home network performance and testing scenarios, we were able to perfect the experience for our users. We eliminated guessing games and tedious manual testing sessions. We are really pleased with the IWL network emulator.”