Jump to content

  • Log In with Google      Sign In   
  • Create Account

Banner advertising on our site currently available from just $5!


1. Learn about the promo. 2. Sign up for GDNet+. 3. Set up your advert!


Android PC Interactions


Old topic!
Guest, the last post of this topic is over 60 days old and at this point you may not reply in this topic. If you wish to continue this conversation start a new topic.

  • You cannot reply to this topic
7 replies to this topic

#1 Paradopolis   Members   -  Reputation: 101

Like
0Likes
Like

Posted 04 November 2013 - 09:02 PM

Hey all!

 

First time here, I am personally just getting started in game development though I have a bit of coding background by now. I am looking to start a side project that has interactions between a mobile platform, specifically android, and PC. Ultimately though, I'd like to be able to put the game on Steam, which I realize is another story but that's not specifically what I am concerned about.

 

So, I would like to avoid having a server component to my game. The idea is that I can have players playing the game on PC, but use the mobile app while they are out in order to collect items and play mini games to "augment" the PC experience. The mobile side of things is, for one reason or another, going to be exclusive to Android.

 

So my concern right now is what I can use to sycnhronize my app with my pc client. Again, I'd like to avoid using a server for it since I'd rather not maintain something that's just going to be a bridge. It seems like there are APIs I could use like the Google Play Game Services but I have no experience with it going cross platform. The other issue is if I want to put my game on Steam, I don't really want to start maintaining the Google API AND the Steam API even if it is possible.

 

I may just be barking up the wrong tree... Anyone have any experience with transferring data from a Mobile app to a PC client? Should I just end up using a server? Are there any APIs available I can look into to help me get data across? 



Sponsor:

#2 Dragonsoulj   Crossbones+   -  Reputation: 2160

Like
0Likes
Like

Posted 04 November 2013 - 09:36 PM

The only options I can think of are:

  • Setting up your own server
  • Renting a server
  • Direct network connection between PC and Android to download current data
  • Direct connection between PC and Android to transfer current data (like USB)
  • Some sort of key/password system to transfer the data

One of the benefits of the server setup would be that they don't require both devices to be connected to each other (network/USB) and on at the same time. You could still use your server with Steam when you make that leap (at least I think you can).


Edited by Dragonsoulj, 04 November 2013 - 09:40 PM.


#3 frob   Moderators   -  Reputation: 24220

Like
0Likes
Like

Posted 04 November 2013 - 10:37 PM

Moving this from the "Coding Horrors" forum to the "Mobile & Console" forum, although it might be a good candidate for the networking forum as well.

Since you don't want to have an intermediate server, you will need to establish some sort of direct connection.

If you assume the devices are connected on the same local network, which is a fairly reasonable requirement for this sort of thing thanks to ubiquitous wifi, there are several options available.

You should include an option of direct IP address entry. This would help with power users and people who understand a bit about networking, as well as help with troubleshooting the hard cases.

Next, since we can assume the wifi connectivity is going to be part of a local network, you can use UDP broadcasts to find listening machines on the network. A few moments on Google searching for Java UDP broadcast brings up sites like this that cover the solution fairly well.

If you implement both, you can put one of the devices in "listen" mode, and then have the other device either connect directly by IP address or do a UDP broadcast scan. Either way it will hit the device that is listening, and that device can communicate back and complete the connection.


You will likely want to add some security and failsafe mechanisms to prove that both ends approve of the transfer, thus preventing someone from accidentally pulling the data from their tablet instead of their phone for example, or in an attack scenario, from a rogue co-worker stealing all the items from their peers.


And a final note, since the system is transmitting data between two unsecured and untrusted machines don't transfer anything with any real value. Any reasonably competent network programmer could monitor the connections and reverse engineer the protocol and keys to give themselves unlimited everything

Check out my book, Game Development with Unity, aimed at beginners who want to build fun games fast.

Also check out my personal website at bryanwagstaff.com, where I write about assorted stuff.


#4 Paradopolis   Members   -  Reputation: 101

Like
0Likes
Like

Posted 04 November 2013 - 10:55 PM

Oh man. You know I was so concerned with thinking about large scale network communication I never even thought of things like just using a local network. I could actually just use JmDNS for something like this pretty easily as well.

 

The more I think about it, the more I think the right way to do this is with a Server, but in a pinch I think using local network discovery will be a good prototype. I can switch that up with a Server without too much effort if I want to invest money in this later.

 

Thanks for the advice guys!

 

And @Dragonsoulj Yeah, I definately could use a server with steam without issue. I'm not sure how exactly, but i'm sure Steam isn't running those MMO's servers for them so it's not entirely sandboxed.

 

Thanks again you two!



#5 frob   Moderators   -  Reputation: 24220

Like
0Likes
Like

Posted 04 November 2013 - 10:56 PM

Following up on how easily it can be reversed... if you tie the collection of items to something like a Steam achievement that is actually quite valuable. Within a few days you would see two types of cheats:

1. Instant items cheat. This would be a simple little script that allows the game to connect and hands it 1000 items for free. No work required.

2. Denial/Steal items cheat. This would be a little more common on a corporate network or college campus, it would continuously broadcast the search for devices. When a device is detected it would automatically collect the items from the player. So an unsuspecting victim hits "listen" on the device, and by the time they hit "scan" on the other device the vandal's script has time to connect to it and reset whatever victories the player may have made.

You cannot do much to prevent the first one, but you should probably add a few steps to reduce the risk of the second.

Check out my book, Game Development with Unity, aimed at beginners who want to build fun games fast.

Also check out my personal website at bryanwagstaff.com, where I write about assorted stuff.


#6 Paradopolis   Members   -  Reputation: 101

Like
0Likes
Like

Posted 05 November 2013 - 08:13 AM

I definately want to have some way of handling cheating. I know without a server to validate data, that's difficult, but I have some things in mind. I definately plan to have some kind of syn / ack / syncack between the mobile and PC so that the user knows that the pc client is requesting to transfer their stuff over, and it should display a random number so that both the pc and mobile can be sure this is the same device. The transfer will work similiar to a bluetooth connection.

 

The second thing I want to add is public private encryption to make it harder for a man in the middle attack to just listen in, figure out the protocol, and make their own item generator (or worse, if its too easy just send the same message they hear over and over again.). All challenges I have learned about, though I've never personally dealt with them. I'm always open to advice though :)



#7 frob   Moderators   -  Reputation: 24220

Like
0Likes
Like

Posted 05 November 2013 - 09:32 AM

The second thing I want to add is public private encryption to make it harder for a man in the middle attack to just listen in, figure out the protocol, and make their own item generator (or worse, if its too easy just send the same message they hear over and over again.).

It won't help because they control both endpoints.

If you control and secure both endpoints, encrypted communications means the outside party does not know the details of the message (although they can infer quite a lot).

If an attacker controls the client endpoint they can attach the app to a debugger and watch the data before it is encrypted. They can fully understand your protocol and inject whatever data they want. They can attack you all day long using a legitimate session. The only thing they cannot do is modify data between other endpoints they don't control. (Example: bad guys can connect to banks and try to send bad data, but they cannot easily modify your connection with the bank.)

If an attacker controls the server endpoint, or an attacker controls both endpoints, they can do anything they want. In this scenario encryption does nothing except provide pebble in the shoe of the attacker, and a false sense of security in the victims.

Check out my book, Game Development with Unity, aimed at beginners who want to build fun games fast.

Also check out my personal website at bryanwagstaff.com, where I write about assorted stuff.


#8 wodinoneeye   Members   -  Reputation: 914

Like
0Likes
Like

Posted 06 November 2013 - 12:23 AM

I kind of wonder if its possible for these games to record a blow by blow action log which could be replayed by any players client (PC or handheld) so that there would be proof of what a player did to get a 'score' or/and 'achievement'.  Playing the game back would make most cheaters visually obvious (and faking it a much bigger headache to try to 'cheat' convinvincingly).

 

Other players in the online score boards (the 'thin' server component) could see what others did in their play (to allegedly get their high  scores)  and be able to point out those (with proof) who are a 'waste of skin' cheater and ridicule them publicly

 

Compressing the (replayable)  log data of sufficent detail is easier for simpler games and data transfer sizes continuously get easier/improve

 

A secondary interest is FOR some people to cheat and do outrageous things in a game (the hacking becomes the 'feat' instead of some false high/fast score.   Playing back amusing scenarios from the community is a component which could add somewhat to the game.


Edited by wodinoneeye, 15 January 2014 - 09:36 AM.

--------------------------------------------Ratings are Opinion, not Fact




Old topic!
Guest, the last post of this topic is over 60 days old and at this point you may not reply in this topic. If you wish to continue this conversation start a new topic.



PARTNERS