Unusual issue with iPhone 4s and wifi

[davehere]

I've had the iPhone for less than a week. And the issue occurs while using my home wifi network. Basically Siri does not work, and I also have difficulty with logging in to specific sites using the app for the site (as opposed to using Safari).

While away from home using the carrier 3G network: Siri works very well. Also, as an example, I can use my local library app for using my library account. AppStore works fine.

At home with a strong wifi signal: Siri tells me that it can't deal with my request right now. And it's not possible to get to the login page on my local library app (The library app continuously loads and then times out). I also have endless loading/timeout issues with the AppStore.

My guess is that it's either an issue with the wireless router/modem or the iPhone itself?

The router uses 801.11b and g. Other devices in the home (MacBook, MacMini, Windows machine, iPad2, NookColor) have no problem and perform as expected with the wifi network.

I have googled and visited forums to troubleshoot this to no avail; and I'm not sure where to look next. So, any ideas on possible router settings or iPhone settings that I need to consider at this point?

More info from a test...

Cellular Data Off / Wireless On

Safari browse to misc websites - OK
Library App - Links on App work except for "Login Page"
Siri - Always says it can't help me right now. Try again in a little while.
Cellular Data On / Wireless Off

Safari browse to misc websites - OK
Library App - Works properly - OK
Siri - Works as expected - OK

 

[Applejuiced]

Yes, its an issue with that router blocking some traffic. Or firewall/port issue.

 

[davehere]

router settings

Any tips on which router settings to investigate? I've already gone over the router settings and everything seems normal. The iPhone is the only device not operating correctly.

 

[davehere]

Solved

I gave my phone a static IP address different from the router assigned one.

Works fine now.

I discovered that my roommate had set up a particular IP address for VPN while working from home a while back. When I got the phone and joined the network, the router assigned my phone that IP address.