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Classification of Mobile Ad Hoc Networks

connectedDevicesWhat is a Mobile Ad Hoc Network? It is a collection of mobile nodes, such devices as PDAs, mobile phones, laptops etc., that are connected over a wireless medium. Thee is no pre-existing communication infrastructure (no access points, no base stations) and the nodes can freely move and self-organize into a network topology.

Such a network can contain two or more nodes. Every owner of a mobile phone equiped with a bluetooth module can build up a direct connection to the other phone and exchange data. It’s the simpliest form of an ad hoc network, one hop piconet. Only one hop is actually not so exciting. Mobile multi-hop ad hoc networks are much more interesting. There are three classes of such networks.

  • MANets – Mobile Ad-hoc Networks. It”s the classical ad hoc network that came from the military sector. These networks were developed to connect planes, tanks, troops at the battlefield. They are completely self-organizing. The other possible areas where they could be applied are disaster recovery, car-to-car communication, home networking. This class of ad hoc networks can be seen as the forefather of the other classes.
  • WMN – Wireless Mesh Networks. Like MANets, but there is a set of nodes, stationary mesh routers which form a wireless multi-hop ad hoc backbone. The mesh routers can be connected to the Internet and thus all the participants of the backbone have an access to the Internet. Imagine you are at the airpot where there are only few access points (mesh routers). You have no direct contact to a one, but still you have an Internet access due to the other guests of the airport. The mesh routers make the routing task more simple and the protocols running on them allow the backbone to be easy to set up and self healing.
  • WSN – Wireless Sensor Networks. This special class of ad hoc networks is used to monitor some phenomenon in a certain area. The nodes have often only the simple task to deliver the monitoring information such as measured temperature, air polution, median speed of the cars on a highway etc. to the minitoring system. The devices partitipating in a sensor network are just special sensors that differ greatly in their purpose from the user devices. Thus the solutions designed for the general multi-hop ad hoc networks where mobile devices execute such applications as Skype, instant messaging, streaming applications etc., just don’t suite for sensor networks.

The idea of ad hoc networks is not that very innovative. It’s almost as old as the Internet. In the last years the interest to the ad hoc networks has grown very much. Especially in the car and entertainment industry.

HockeyApp in a praxis

hockeyapp_logoHockeyApp is a solution for collecting app crash reports, get feedback from users and distribute your betas. It can be integrated with apps for iOS, Android and Windows. This week I had an opportunity to evaluate it and now want to deal with my experience.

 

 

 

  • Integration into an iOS app is really easy. Using Cocoapods it’s just one entry in your podfile:
    pod 'HockeySDK', :subspecs => ['AllFeaturesLib']

    Be sure to enable AllFeaturesLib if you need a feedback functionality.

  • To start using HockeyApp in your project, you first need to register the app under your HockeyApp account. After doing that, you get an identifier for your app. This one you’ll need in your project
  • With these lines of code you initialize HockeyApp and get it running:
    [[BITHockeyManager sharedHockeyManager] configureWithIdentifier:@"yourHockeyAppAppId";
    //you can add the following line before calling startManager to disable the In-App-Update feature
    [[BITHockeyManager sharedHockeyManager] setDisableUpdateManager:YES];
    // Do some additional configuration if needed here
    [[BITHockeyManager sharedHockeyManager] startManager];
    [[BITHockeyManager sharedHockeyManager].authenticator authenticateInstallation]; // This line is obsolete in the crash only builds
    
  • From now on all crash reports appear  automatically at the backend side
  • To integrate a feedback form  just build in two buttons into your app with corresponding handlers:
    - (IBAction)composeFeedbackAction:(id)sender
    {
        [[BITHockeyManager sharedHockeyManager].feedbackManager showFeedbackComposeView];
    }
    
    - (IBAction)feedbackListAction:(id)sender
    {
        [[BITHockeyManager sharedHockeyManager].feedbackManager showFeedbackListView];
    }
    
  • At the backend the administrator can view user feedbacks and reply them. In the app the user gets automatically notified about new replies.
  • Integration with Jenkins is also a matter of a few minutes. There is a plugin for uploading .ipa files to the HockeyApp. Depending on your needs, this Jenkins-plugin can release the app version immediately into a download area of the HockeyApp. The download area can be accessed then by beta-testers or if you define also by a public.

All in all HockeyApp is a pretty helpful tool. Maybe it’s not a suitable solution for individual developers because of the pricing model, but for companies it can be an attractive alternative.

 

End of the story for Microsoft Band

Microsoft BandAccording to numerous rumors there might be no follower for Microsoft Band 2. This is still not officially confirmed by Microsoft, however, this seems to be only a question of time.

Personally I cannot really follow this strategy step of Microsoft. Weak market? This is the only explanation I can think of. Yes, Microsoft Band 2 is not perfect. But still it has its fans. Currently, its the only device on the markt with such a wide range of sensors.

I had also an opportunity to play a bit with its SDK. It makes a pleasant impression. The only shortcoming I can point on is the way for accessing the health data. It is only possible to access the data in real time. There must be always a bluetooth connection between your iPhone/Android/Windows  app and the band, during the native “Microsoft Band” app can access the internal memory of the band and read data stored on it.

If the next generation of the Microsoft band had been extended by an interface for accessing the data stored on the band, it would make it to an attractive wearable. At least from the app developing point of  view.

Smartphones und die Holzerfassung

forestNoch bis vor kurzem hieß es Smartphones und Tables im Wald seien nur ein Spielzeug. Wie soll es überhaupt gehen, die Holzmessdaten in strömendem Regen oder prallender Sonne, dazu oft noch ohne Internet zu erfassen?  Doch die Zeiten haben sich geändert. Die Geräte werden immer tauglicher für den Einsatz im Wald. Dabei müssen es nicht immer die teueren Toughbooks sein. Auch iPads und Android Geräte lassen sich durch stoßfeste und wasserdichte Cases zu einem praktischen Werkzeug bei der Holzerfassung aufrüsten.

Viele Forstbetriebe und Holzankäufer haben das Potenzial von Smartphones/Tablets bereits erkannt und integrieren diese in ihre Abläufe. Die Holzmessdaten werden nicht mehr mit Stift und Papier aufgenommen, was früher immer fehlerträchtig und lästig war, sondern werden direkt in der App angegeben. Die Apps sind häufig in der Lage die Holzdaten mit einem Verwaltungssystem zu synchronisieren. Die Synchronisation erfolgt wenn die Internetverbindung vorhanden ist. Bis dahin werden Holzmessdaten auf dem Smartphone/Tablet aufbewahrt.

 

New look, new goals

field-viewI gave up my private web site i-gorod.org and now moved my internet presence to a new domain. It is not only the domain name that was changed, but also the concept. i-gorod was once a chat for the friends of mine. Afterwards I made it to a developer blog and never found time to full it with content.

igoMobile is in opposite my business card. On one hand it enlightens the projects I work on. On the other hand it will help me to maintain the contacts, extend my network and find new challenges.