Siri's Service Stutters Spark Strife

Siri, the voice-activated virtual personal assistant that's enamored owners of the iPhone 4S since the device was launched in October, has been hit by another service outage.

Users began posting complaints about the latest outage to the Twitter Siri page on Wednesday, saying they couldn't get Siri to respond to voice commands because it couldn't connect to the network.

Siri connects to Apple's servers to process requests, and there's been speculation that perhaps the servers were overwhelmed by the unexpectedly high volume of traffic coming from Siri users.

Alternatively, wireless bandwidth or connections may be playing a role in the outages, Charles King, principal analyst at Pund-IT, told MacNewsWorld.

"Since Siri was the most notable new feature on the [iPhone 4S] and Apple hyped it accordingly, not having the necessary resources internally or via external providers suggests a stunning lack of foresight," King suggested.

Apple did not respond to requests for comment by press time.

Oy, Manzana! Que Pasa?

Siri works out of the box in a number of languages, according to Apple.

It uses the processing power of the dual-core A5 chip in the iPhone 4S and communicates with Apple's data centers using 3G and WiFi networks.

The first outage reportedly occurred immediately after the iPhone 4S was launched last month, and the latest outage hit on Thursday.

Virtual personal assistants like Siri build on the information and services of the Web, and the challenges they face include semantics, context awareness, service delegation, and mass personalization, Tom Gruber, one of the cofounders of Siri, said in this presentation at the Semantic Technologies Conference in June 2009.

More on VPAs

Siri and other virtual personal assistants are essentially shared reusable knowledge-based systems, and they pose special requirements for interoperability, Gruber said in a 1993 paper on principles for the design of ontologies used for knowledge sharing.

"The more complex these features get, the more points of failure they have," Allen Nogee, a research director at In-Stat, told MacNewsWorld.

On the other hand, Siri is still in beta, and Gruber said during his presentation that virtual personal assistants get better with time.

That's probably because they amass more data in their knowledge bases and can make better inferences.

Solving Siri's Sounds of Silence

To date, Siri's outages have been relatively short, but that doesn't help matters.

"Like all outages, if they occur at the point in time that affects you, they are serious for you," In-Stat's Nogee pointed out.

"If I were a businessperson considering using Siri in my organization, this outage would definitely make me think twice," Pund-IT's King said. "There are other similar options such as Voice Assist that are definitely ready for prime time today."

Voice Assist lets users make calls, manage their emails, and send text messages from any phone using voice commands.

However, Siri is still in beta, and therefore people probably don't rely on it working too well, although that could change as time goes on, Nogee stated.

"It's important that Apple learns from this and gets the kinks out," Nogee added.

In the short run, Apple might tap Amazon S3 servers, but in the longer term the company might leverage its own cloud data centers or deploy more resources, King remarked.

This is the second technical problem to hit the iPhone 4S. It's already suffering from excessive power consumption, evoking widespread user complaints. Apple on Wednesday told AllThingsD this power issue was caused by a bug in iOS 5.