| # The Share section With JAlbum you don't have to publish an album to share it with friends. JAlbum is equipped with a web server that lets you share albums straight from your local hard disk. Your visitors still only need a plain web browser to view your albums. The process is very simple: Make an album, then go to the "Share" tab and press "Share current album". You can have several albums shared at the same time! When an album is shared you just copy the address that JAlbum generates and paste it into chat clients like Messenger and Skype. As your computer and JAlbum needs to be running for album sharing to work this isn't probably suitable for long-term albums, but there are several cases when one is chatting with friends and wants to show them the images from last weeks trip or party. JAlbum file sharing has many advantages: Albums can be shared instantly after being made. No signing up for a web account or upload delay. No size barriers other than the size of the local hard disk Viewers don't need any special client software, only their web browser (unlike many other peer-to-peer networks) ## User interface controls Shared albums -Displays your shared albums and lets you select them for editing. Share current album -Click this button after making an album and it will be instantly shared Start -Manually start the web server that does the album sharing Stop -Stop the web server. This instantly stops all album sharing Settings... -Open the web server settings dialog box (see below) Name (URI) -This name identifies each shared album and also forms part of the final album address Local path -Path to album directory to share Address -Web address to shared album. Copy and paste address to friends when chatting using Messenger or Skype for instance Go to -Open shared album in your web browser Security settings... -Open dialog window that allows you to password protect each album Active -Toggle sharing of this album Update -Update changes made to the current shared album Remove -Remove this shared album ### Web server settings dialog Port -TCP port to listen to between 1 and 32767. JAlbum tries to pick a unique port number to allow JAlbum file sharing to work even though multiple machines use JAlbum file sharing behind a firewall (actually a gateway with NAT translation). Only one program can listen on a specific port on each machine so if you get an error while starting the web server, just change to another (random/free) port number. Hostname -Name that identifies this server on the Internet. If left blank, the IP address will be used. You can get a unique friendly identifying name for your machine by signing up with the free DynDNS service for instance Start web server when JAlbum starts -It is recommended that you set this setting in order to make your albums more available Establish port mapping in firewall -Most home users that have a broadband connection are behind a broadband router that contains a firewall (typically called "the firewall"). This box typically does so called address translation (NAT) in order to allow several machines to share a single IP address on the Internet. For JAlbum file sharing to work with these boxes one needs to allow incoming "TCP" traffic to the relevant port and pass it to the computer running JAlbum file sharing. If your firewall supports the common UPnP (Universal Plug and Play) standard, JAlbum will attempt to configure this for you automatically as you start the web server No logging -Do not log album sharing activity Log to system console window -Log album sharing activity to the system console window (Help menu) Log to file -Log album sharing activity to file. JAlbum will use the NCSA log file standard. Log date format -Date format to use when logging. See date format documentation. Log file name -File name for log file (defaults to logging to JAlbum install directory). You can also specify a full path ## Security information JAlbum will sense if you are behind a firewall and try to open a "port forwarding" to let web traffic in. When you close JAlbum, the sharing will stop and the port forwarding will be removed again. For all this to work you need to have a UPnP enabled firewall. Most firewalls for home use are UPnP capable today. If you don't have UPnP support, you can always configure this port forwarding manually. JAlbum will assist you in this process. So what are the security implications of this? I would say hardly any. If a malicious software has made it into your local network it can pass information back and forth through a firewall even if port forwarding isn't configured. Just opening a port forwarding in itself doesn't cause any harm. Second, to hack a computer running any server, the classic approach is to inject unexpected data that causes so called "buffer overflow" inside the listening application. However with Java such attacks are not possible as the Java machine checks all buffer boundaries. This makes Java web servers very safe. Third, JAlbum uses the popular Jetty web server that is the base for J2EE application servers such as Geronimo, JBoss, and JOnAS. Jetty is also included in many products including IBM Tivoli, Sonic MQ and Cisco SESM.