Hello, For all of the reasons described, it may not be possible, using TCP.
It may be possible using UDP, however. I have been successful at creating a bidirectional conversation between a [Verizon] Droid and a PC using UDP, while the same code failed miserably on T-Mobile. Conclusion: T-Mobile filters out the packets, Verizon allows them. The only question then is how they might handle hairpin routing, and of course this depends on where the NAT is located. I will test this as soon as I get my hands on another Droid. So, the scenario that *may* work would require that you: 1) Have some external server to help negotiate the conversation 2) Use UDP rather than TCP Scott SoftwareForMe.com On Thu, Mar 4, 2010 at 10:04 PM, Bob Kerns <[email protected]> wrote: > It's more than that. There's no reason for there to be any routes for > anything except phone to APN, and no reason for them to not filter out > all incoming requests and inter-phone traffic as a security measure. > > You can't persuade your cable modem to let you talk directly to your > neighbor, either. > > Even if you found cases that worked, with phones hopping from tower to > tower, and there being no reason for it to work as a matter of policy, > I don't think it's anything you could ever make robust and reliable. > > On Mar 4, 5:26 pm, Mark Murphy <[email protected]> wrote: > > Jon Dixon wrote: > > > Thanks for your response. Before I abandon this design, please > > > comment on this use case. Let's say I have two phones on the same > > > carrier (Verizon). Would not these phones be on the same side of the > > > NAT firewall? > > > > Not necessarily. The NAT could be applied at the tower, the central > > office, or any number of other points that would be in between the two > > users. > > > > -- > > Mark Murphy (a Commons Guy)http://commonsware.com| > http://twitter.com/commonsguy > > > > Android 2.0 Programming Books:http://commonsware.com/books > > -- > You received this message because you are subscribed to the Google > Groups "Android Developers" group. > To post to this group, send email to [email protected] > To unsubscribe from this group, send email to > [email protected]<android-developers%[email protected]> > For more options, visit this group at > http://groups.google.com/group/android-developers?hl=en > -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en

