[[TranslatedPages]]
= Preferences > Connection settings = 

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This is work in progress which is neither available in <tt>latest</tt> nor in <tt>tested</tt>. The corresponding features will be available shortly. 
Please check the JOSM Message of the Day.
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[[TOC(inline)]]

== The URL to the OSM server ==

=== Downloading and uploading to the default server ===

[[Image(use-default-api-url.png)]]

Most JOSM users want to exchange geo data with the standard OSM server operated by the OSM community. 

Tick the respective checkbox in order to download from and upload to the standard server (see screenshot above). This is the default setting.

=== Advanced option: Downloading and uploading to a custom server === 
Some JOSM users need to configure the API URL of an OSM server because they are working with a custom server:
  * Some users are working with local installations of the OSM server
  * Some users are working with development and test instances of the OSM server (for instance with [http://api06.dev.openstreetmap.org]).

[[Image(use-custom-api-url.png)]]

In order to use a custom URL:
  1. Remove the tick in the checkbox for the standard API URL (see screenshot above)
  2. Enter the API URL
  
Click on '''Validate''' to test whether an OSM API server is available at the given URL. If so, JOSM will display the icon [[Image(source:/trunk/images/dialogs/changeset/valid.png)]] to the right of the input field for the API URL. If the URL isn't valid, JOSM will display the icon  [[Image(source:/trunk/images/warning-small.png)]].


== Authentication Settings ==

=== Working anonymously or with an OSM account ===

You don't need to identify and authenticate yourself provided that you neither upload data to the OSM server nor download data for which you must authenticate first.

If you work '''anonymously''' you are allowed
  * to download geo-data from the OSM server and save it to a local file 
  * to download public GPS traces from the OSM server 
  * to load geo data from a file, edit it, and save it back to a file 

However, you can't
  * upload geo-data to the OSM server. You can't created, update, or close changesets either. 
  * download your private GPS traces 

You are recommended to [http://www.openstreetmap.org/user/new?referer=%2F create an OSM user account]. By using [http://www.openstreetmap.org/user/new?referer=%2F this form] you can choose an '''OSM username''' and an '''OSM password''' both of which you will use below. 

=== Basic authentication ===
Basic authentication is the basic mechanism to authenticate yourself at the OSM server. 

Here's a screenshot of the preferences panel for basic authentication: 

[[Image(basic-authentication.png)]]

To use Basic Authentication

  1. Go to the tab '''Authentication''' in the Connection Preferences
  2. Select the authentication method '''Basic authentication'''
  3. Enter your OSM username and your OSM password 

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<strong>Warning!</strong><br/>
The password is stored in plain text in the JOSM preferences file. 
Furthermore, it is transferred <strong>unencrypted</strong> in every request sent to the OSM server. 
<strong>Do not use a valuable password.</strong>
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=== OAuth based authentication ===
[http://oauth.net/ OAuth] is an open protocol to allow secure API authorization  in a simple and standard method from desktop and web applications. The OSM server supports OAuth in addition to basic authentication. 

OAuth has two major advantages over basic authentication:
  1. Your OSM password doesn't have to be saved in clear text in the JOSM preferences file.
  2. Your OSM password has to be transferred '''only once''' over the Internet, in contrast to basic authentication where your OSM password is trasferred as part of every request sent from JOSM to the OSM server. 

{{{
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<p style="background-color:rgb(253,255,221);padding: 10pt; border-color:rgb(128,128,128);border-style: solid; border-width: 1px;">
<strong>Warning!</strong><br/>
Currently, the OSM server doesn't offer a secure communication channel. Even if you use OAuth your password is therefore transferred <strong>once in clear text</strong> over the Internet. <strong>Do not use a valuable password</strong> until the OSM server provides a secure communication channel (HTTPS).
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For advanced users, OAuth has addional advantages:
  * With OAuth you can generate restricted Access Tokens which you given somebody else such that another mapper can act on your behalf. For instance, a mapper could generate an Access Token which grants somebody else the right to download its private GPS traces. Even if he gives this Access Token to somebody else, his OSM password is kept private. In addition, he can revoke the special Access Token at any time. JOSM supports this kind of advanced configuration in the [wiki:/Help/Dialog/OAuthAuthorisationWizard OAuth Autorisation Wizard] with the authorisation procedure '''Manual authorization'''. 

To use OAuth based Authentication

  1. In the Connection Preferences go to the tab '''Authentication'''
  2. Select the authentication method '''OAuth based authentication'''
  3. Click on '''Authorise now''' to launch the [wiki:/Help/Dialog/OAuthAuthorisationWizard OAuth Autorisation Wizard] (see screenshot below)

[[Image(oauth-preferences-step-1.png)]]

This will launch the [wiki:/Help/Dialog/OAuthAuthorisationWizard OAuth Autorisation Wizard]. Use one of the available authorization procedures in this dialog to get a valid '''Access Token'''. 

JOSM displays the retrieved Access Token in the preferences panel (see screenshot below):

[[Image(oauth-preferences-step-2.png)]]

Unselect the checkbox '''Save to preferences''' if you don't want to save the Access Token in the JOSM preferences. If you don't save it the Access Token will be lost when you close JOSM. If you later startup JOSM again you will have to retrieve a new Access Token to work with OAuth based authentication again. 

Click on '''Test Access Token''' to submit a test request with the token to the OSM server. JOSM will analyse whether this token is authorized to access the OSM server.

Click on '''New Access Token''' to generate a new Access Token. 

==== Advanced OAuth parameters ====
Select the checkbox '''Display Advanced OAuth parameters''' to display the important OAuth parameters
  * the [http://oauth.net/core/1.0/#anchor3 Consumer Key] and the [http://oauth.net/core/1.0/#anchor3 Consumer Secret] identifying JOSM as OAuth consumer
  * the Request Token URL where JOSM can retrieve [http://oauth.net/core/1.0/#anchor3 Request Tokens]
  * the Access Token URL where JOSM can retrieve [http://oauth.net/core/1.0/#anchor3 Access Tokens]
  * the Authorise URL where JOSM users are redirected to to authorise a Request Token

[[Image(oauth-advanced.png)]]

== Proxy Settings ==
JOSM communicates with the OSM server using the Hypertext Transfer Protocol ([http://en.wikipedia.org/wiki/Http HTTP]). If required it can relay its requests through a [http://en.wikipedia.org/wiki/Http_proxy HTTP proxy] or a [http://en.wikipedia.org/wiki/SOCKS SOCKS proxy].

  1. Go to the tab '''Proxy settings''' in the Connection Preferences
  2. Select one of the available options and enter additional configuration parameters 
  3. Save the preferences 

[[Image(proxy-settings.png)]]


=== Using the standard system proxy ===
If you always want to use the proxy defined as standard proxy on your computer you have to startup JOSM with a special command. The command line has to include the parameter {{{-Djava.net.useSystemProxies=true}}}, for instance 

  {{{java -Djava.net.useSystemProxies=true -jar josm.jar}}}


== File Backup ==