Remotely extend AWT over network protocol?

Hello, I am planning a highly interactive web-oriented application (a control panel). I have considered implementing it with pure HTML+JSP, possibly with some AJAX, but I don't really have the time to learn the AJAX toolkits out there, not does it seem fully worth it for this app.
The best solution would be to use a Java Applet, since it's easy to build a GUI in today's IDEs, and it integrates well with what I know. The problem is, this application must access an SQL database and possibly some other "private" classes that I don't want anyone snooping in. I could learn how to manaully send data over the HTTP connection from the applet, maybe even using tricks to asychronously perform this, but things become a bit confusing, and hard to scale.
What I'd like to be able to do is take an existing solution, hopefully open-source, and use it to extend an AWT/Swing interface, hopefully via an HTTP connection (for HTTP proxy/firewall's sake, if there is one), which simply renders the AWT interface on the client's end, but sends back events to the server. This way, it'd be transparent and convient. The client would get a GUI to use, but would be unable to sneak into classfiles in attempt to exploit the application. The app would essentially run on the server, but be rendered to the client in an applet (it'd be so seamless you could do it with any AWT-based app).
It'd be nice if I could specify code/classes to work client-side (i.e. "business logic"), to lower some networking load, but I may be getting a bit too wishful.
I am prepared to implement this myself, but I know a more robust and feature-rich AWT-stand-in API must already exist!
Thanks for any help you can provide!

I've been googling like crazy and sadly I've only come to two examples of what I'm talking about...but...
1) "RAWT - Remote AWT" - http://www.vm.ibm.com/java/rawt.html#terms - This is an old IBM project that is no longer supported. It appears to have been designed for a specific server series, but the binaries are nowhere to be found anyway. It basically replaced the standard AWT classes with it's own to extend the GUI to a remote client.
2) This is more of an example that what I really need ( http://www.bmsi.com/tuipeer/ ) - it renders an AWT interface simply as text (put simply), in order to be compatible with older terminal systems. If I were crazy, I could throw this in with an SSH or telnet connection and have quite an archaic looking GUI, but I certainly wouldn't want to do that!

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I've had a Samsung network extender for over a year and it's been great. About a week ago, my iPhone 5 stopped connecting to it. I've never had problems with this. All the lights on the extender are blue, so it seems it's working fine. Any suggestions

I've had a Samsung network extender for over a year and it's been great. About a week ago, my iPhone 5 stopped connecting to it. I've never had problems with this. All the lights on the extender are blue, so it seems it's working fine. Any suggestions?

Oh no! Lets ensure that you are connected. Have you tried to reset the Network Extender? Are other devices able to connect to the Extender? Is your Internet service up and running?
Share details so that we can help!
Thank you,
LenaA_VZW
Follow us on Twitter @VZWSupport

Best way to share aperture library over network on two computers?

I've read several posts about doing this and most recommend using an external HD and just hot swapping. However, is their not a better alternative? Can I not share my library over the network, or just remote connect to the other computer?
Thanks for the help!

Hi Terence and Leonie,
You can run several Aperture on the same computer as long as all Aperture are using distinct libraries.
What Aperture does is to create a simple lock file in <your Aperture library>.aplibrary/Database/apdb The lock file contains the PID of the process. So not two Aperture could open the same library (although I don't know how good they have manage the concurrent creation, locking, verification of this lock, this is a typical and difficult software engineering problem)
Anyway, I have not said that Aperture supports concurrent editing. That a file is a database or a simple text file, you have basically the same issues on network or in concurrent environment. So if the folder structure holds simple, flat text file or xml object or databases, it is still a bunch of files (this is a UNIX system by the way ).
Aperture contains more than one SQLlite file, there are some at the root folder, some under Database/apdb etc. there are also XML files that could be used as database.
Anyhow, editing a file (SQLlite, XML, txt, doc, etc.) either on a share or locally is plain similar. The drive can fail too, although much less likely than the network.
Network file edition can have a few shortcomings, but nothing that when known can be blocking.
Locking files over the network can however be tricky and depends largely on the network protocol used (NFS, SMB/CIFS or AFP just to name a few). In addition, if you import files from /Users/foo/Photos in Aperture (without copying them within Aperture), they might not be visible from another computer or only the previews, as the path /Users/foo/Photos is not "visible" from the other computer.
What really is a problem when you put a file not locally is the file system type and its features. HFS+ supports extended attributes (metadata), many other file systems support these but the API (how the software, such as Aperture, access this feature) might not be similar, in addition the amount of metadata or their structure might differ from file system to another. And this is where you might lose information.
A tool like Dropbox is pretty good at maintaining the metadata across different computers, and it has been adapted to do so for OS X specifically (and also for Linux and Windows).
The second problem is if you would have a Mac and share via SMB (the Windows share network protocol, aka CIFS on recent Windows versions) the library, SMB might not support the reading and writing of HFS+ metadata, thus data loss might occur.
Apple is just warning us of all these shortcomings, and advise to use local storage formatted as HFS+. Because even a local external disk formatted as NTFS or other file system could be a problem.
However, power users who understand the risks and limitations of a network share (in general) can create a disk image on a share (even if it is SMB). As for OS X, once the disk image is mounted, it is just like any other local hard disk, it is just "slower" especially latency wise. OS X supports perfectly disk image mounted on a share, it takes care of properly synchronising it.
Of course, due to the nature of the link between the application data and where they are stored, in case of application or OS crash, the amount of data loss could be greater than when the data are held locally.
I hope this clarify better my post.
Note: another shortcoming of having it on the network is: Aperture lock the library by creating a file with a process ID. If the same library is opened from another computer on the network, this other Aperture instance might see the lock file and could perhaps not find the corresponding running process. This Aperture instance might then decide to ignore the lock and proceed with opening the library. This might have some consequences.
But I haven't developed Aperture so I don't know how it would behave

Applet Security over Network

Hi, I have an Applet that requires access to the system clipboard of the client. I have never had to sign an applet before, and wanted to know if I need to have a Verisign certificate or equivalent in order to distribute this over network where I work.
The network uses NT authentication so is already secured and trusted, do I really need to go to the expense of getting a certificate just to be able to a small number of staff to use an applet at work? Or is there another way?
Many thanks in advance
AMD

Though there is already a 10 step approach for signing applets, I'll try to explain how you can sign an applet with a self signed certificate (free) and be able to manage your applet on your server so clients do not need to have a policy file on there computer. The only disadvantage of this approach is that a self signed certificate expires after one year, but since you can update your certificate on the server this should not be a big problem.
create your keystore with keypair:
keytool -genkey -keystore your_company.store -alias programmer_name
fill in the information for name company etc.
export the certificate from the store:
keytool -export -keystore your_company.store -alias programmer_name -file certificate_name.cert
Make a JAR file for your classes:
jar cvf your_applet.jar *.class
and sign your JAR file
jarsigner -keystore your_conpany.store your_applet.jar certificate_name
I always keep my certificates in another store. To this:
keytool -import -keystore all_your_certificates.store -alias programmer_name -file certificate_name.cert
Now you have got a signed applet. To post this on a server do this:
Inside the policy file you can specify the keystore location:
keystore "http://intranet.mysoft.com/admin/all_your_certificates.store", "JKS";
grant signedBy "programmer_name"
{permission java.awt.AWTPermission "accessClipboard";
permission java.awt.AWTPermission "createRobot";
permission java.awt.AWTPermission "readDisplayPixels";
Place the all_your_certificates.store and policy file on the intranet server.
The advantage of this way of working is everything can be managed remotely. As you can see, the applets that are signed by the certificate have permission for accessing the clipboard. You can specify different security settings for each certificate in the policy file.
Every visiter can now access your applet without needing the certificate installed because it can be found on the server.

Pulseaudio over network

Hi, I have a Thinkpad R400 and I also have an ArchLinux i686 home server connected via spdif to my home sound system. When I used debian Lenny, I got really old pulseaudio server, GUI, everything - it worked though. It worked only if I was logged in via X server (graphically) locally or remotely. So I installed Arch (thinking using the same OSes can ease things ... I was so naive) and I cannot get this pulse sound server running. First of all I cannot start pavucontrol over ssh tunnel, it has to be from within logged in session. my /etc/hosts.allow:
ALL:ALL
I would like to have the pulseaudio started as a daemon, not having to start X at all. I am unable to start it though. It just says FAILED and gives no reason at all. please tell me what should I do, what how-to should I abide or... Thank you

Okay, server side /etc/pulse/daemon.conf
daemonize = yes
fail = no
allow-module-loading = no
allow-exit = no
use-pid-file = no
system-instance = yes
enable-shm = no
shm-size-bytes = 64 # setting this 0 will use the system-default, usually 64 MiB
; lock-memory = no
; cpu-limit = no
; high-priority = yes
; nice-level = -11
; realtime-scheduling = yes
; realtime-priority = 5
exit-idle-time = -20
; scache-idle-time = 20
; dl-search-path = (depends on architecture)
; load-default-script-file = yes
; default-script-file =
; log-target = auto
; log-level = notice
; log-meta = no
; log-time = no
; log-backtrace = 0
; resample-method = speex-float-3
; enable-remixing = yes
; enable-lfe-remixing = no
; flat-volumes = yes
; rlimit-fsize = -1
; rlimit-data = -1
; rlimit-stack = -1
; rlimit-core = -1
; rlimit-as = -1
; rlimit-rss = -1
; rlimit-nproc = -1
; rlimit-nofile = 256
; rlimit-memlock = -1
; rlimit-locks = -1
; rlimit-sigpending = -1
; rlimit-msgqueue = -1
; rlimit-nice = 31
; rlimit-rtprio = 9
; rlimit-rttime = 1000000
; default-sample-format = s16le
; default-sample-rate = 44100
; default-sample-channels = 2
; default-channel-map = front-left,front-right
; default-fragments = 4
; default-fragment-size-msec = 25
server side /etc/pulse/system.pa
### Automatically load driver modules depending on the hardware available
.ifexists module-udev-detect.so
load-module module-udev-detect
.else
### Alternatively use the static hardware detection module (for systems that
### lack HAL support)
load-module module-detect
.endif
### Load several protocols
.ifexists module-esound-protocol-unix.so
load-module module-esound-protocol-unix
.endif
load-module module-native-protocol-unix
### Automatically restore the volume of streams and devices
load-module module-stream-restore
load-module module-device-restore
### Automatically restore the default sink/source when changed by the user during runtime
load-module module-default-device-restore
### Automatically move streams to the default sink if the sink they are
### connected to dies, similar for sources
load-module module-rescue-streams
### Make sure we always have a sink around, even if it is a null sink.
load-module module-always-sink
### Automatically suspend sinks/sources that become idle for too long
load-module module-suspend-on-idle
### Enable positioned event sounds
load-module module-position-event-sounds
### Automatically restore volumes
load-module module-volume-restore table="/var/pulse/volume-restore.table"
load-module module-native-protocol-tcp auth-anonymous=1
#load-module module-native-protocol-tcp
server side /etc/pulse/default.pa
.nofail
### Load something into the sample cache
#load-sample-lazy x11-bell /usr/share/sounds/gtk-events/activate.wav
#load-sample-lazy pulse-hotplug /usr/share/sounds/startup3.wav
#load-sample-lazy pulse-coldplug /usr/share/sounds/startup3.wav
#load-sample-lazy pulse-access /usr/share/sounds/generic.wav
.fail
### Automatically restore the volume of streams and devices
load-module module-device-restore
load-module module-stream-restore
load-module module-card-restore
### Automatically augment property information from .desktop files
### stored in /usr/share/application
load-module module-augment-properties
### Load audio drivers statically (it's probably better to not load
### these drivers manually, but instead use module-hal-detect --
### see below -- for doing this automatically)
#load-module module-alsa-sink
#load-module module-alsa-source device=hw:1,0
#load-module module-oss device="/dev/dsp" sink_name=output source_name=input
#load-module module-oss-mmap device="/dev/dsp" sink_name=output source_name=input
#load-module module-null-sink
#load-module module-pipe-sink
### Automatically load driver modules depending on the hardware available
.ifexists module-udev-detect.so
load-module module-udev-detect
.else
### Alternatively use the static hardware detection module (for systems that
### lack udev support)
load-module module-detect
.endif
### Automatically load driver modules for Bluetooth hardware
.ifexists module-bluetooth-discover.so
load-module module-bluetooth-discover
.endif
### Load several protocols
.ifexists module-esound-protocol-unix.so
load-module module-esound-protocol-unix
.endif
load-module module-native-protocol-unix
### Network access (may be configured with paprefs, so leave this commented
### here if you plan to use paprefs)
#load-module module-esound-protocol-tcp
load-module module-native-protocol-tcp
load-module module-zeroconf-publish
### Load the RTP reciever module (also configured via paprefs, see above)
load-module module-rtp-recv
### Load the RTP sender module (also configured via paprefs, see above)
#load-module module-null-sink sink_name=rtp format=s16be channels=2 rate=44100 description="RTP Multicast Sink"
#load-module module-rtp-send source=rtp.monitor
### Load additional modules from GConf settings. This can be configured with the paprefs tool.
### Please keep in mind that the modules configured by paprefs might conflict with manually
### loaded modules.
.ifexists module-gconf.so
.nofail
load-module module-gconf
.fail
.endif
### Automatically restore the default sink/source when changed by the user during runtime
load-module module-default-device-restore
### Automatically move streams to the default sink if the sink they are
### connected to dies, similar for sources
load-module module-rescue-streams
### Make sure we always have a sink around, even if it is a null sink.
load-module module-always-sink
### Honour intended role device property
load-module module-intended-roles
### Automatically suspend sinks/sources that become idle for too long
load-module module-suspend-on-idle
### If autoexit on idle is enabled we want to make sure we only quit
### when no local session needs us anymore.
load-module module-console-kit
### Enable positioned event sounds
load-module module-position-event-sounds
### Cork music streams when a phone stream is active
load-module module-cork-music-on-phone
# X11 modules should not be started from default.pa so that one daemon
# can be shared by multiple sessions.
### Load X11 bell module
#load-module module-x11-bell sample=bell-windowing-system
### Register ourselves in the X11 session manager
#load-module module-x11-xsmp
### Publish connection data in the X11 root window
#.ifexists module-x11-publish.so
#.nofail
#load-module module-x11-publish
#.fail
#.endif
### Make some devices default
#set-default-sink output
#set-default-source input
please tell me what else should I post. Also, is it necessary to have the cookie synced over network (nfs, sshfs etc...) or is it OK if I just copy it?

Difference between an Extended 802.11n Network and a WDS Network?

If the question is confusing, I'm referring to the article here...
http://www.macgurulounge.com/started-learn-extend-airport-networks-wds/
Why would I choose one over the other? Is it just that WDS works with mixed (b/g/n) networks, while an "extended n" requires every station to be n-compatible?
Thanks.

The "extend a wireless network" setup maintains "n" speeds on the network. All of the AirPorts on the network must be capable of "n" operation in order to run the configuration.
WDS runs on maximum "g" speeds only, even if you have a newer "n" AirPort device on the network. If you have any "g" AirPort router on the network, you must use the WDS configuration. It's not possible to run the "extend" setup on an older "g" AirPort device.
There's a huge bandwidth penalty using WDS. For each "remote" on the network, the bandwidth on the entire network is cut in half. So, with a "main" and "remote" operating on a WDS setup, you'll have in effect, a "g" wireless network running at 1/2 speed. Not very attractive, but you have no alternative if any of the routers on the network are "g" products.
If all of the AirPorts are newer "n" devices, you would obviously want to use the "extend" setup to maintain "n" speeds on the entire network with much less bandwidth loss compared to WDS.

Extending airport express network with other airport express

I am trying to extend my airport express based wifi network, using two more units.
All airport express units are 802.11n capable.
My main question is about the band frequency: does it matter whether I use 2.4 or 5 ghz ?
I have some success when using 2.4 ghz, but I am having zero success when using 5ghz on the main unit (the one connected via ethernet to the router). The other two units are set up to "extend a wireless network".

Welcome to the discussion area, Giovanni!
While it is not exactly correct to say that you almost need line-of-sight between the AirPort Express devices for 5 GHz to work effectively, a number of users are finding this to be the case. 5 GHz signals are much weaker than 2.4 GHz signals, so they do not travel well over distance or pass through obstructions very well.
Unless you almost do have line-of-sight between the devices, you are probably going to get better results by setting up the "main" AirPort Express on the 2.4 GHz band and use the others to "extend" that band.
The "extend" setup works like the hub and spokes of a wheel. Your main AirPort Express is the "hub" and the other devices are located at the ends of the the "spokes". The remote devices communicate directly to the hub, not to another device at the end of another spoke, so it's not possible to "extend" a device that is already setup to "extend".

Help! Saving an image to stream and recreating it on client over network

Hi,
I have an application that uses JDK 1.1.8. I am trying to capture the UI screens of this application over network to a client (another Java app running on a PC). The client uses JDK 1.3.0. As AWT image is not serializable, I got code that converts UI screens to int[] and persist to client socket as objectoutputstream.writeObject and read the data on client side using ObjectInputStream.readObject() api. Then I am converting the int[] to an Image. Then saving the image as JPEG file using JPEG encoder codec of JDK 1.3.0.
I found the image in black and white even though the UI screens are in color. I have the code below. I am sure JPEG encoder part is not doing that. I am missing something when recreating an image. Could be colormodel or the way I create an image on the client side. I am testing this code on a Win XP box with both server and client running on the same machine. In real scenario, the UI runs on an embedded system with pSOS with pretty limited flash space. I am giving below my code.
I appreciate any help or pointers.
Thanks
Puri
     public static String getImageDataHeader(Image img, String sImageName)
         final String HEADER = "{0} {1}x{2} {3}";
         String params[] = {sImageName,
                            String.valueOf(img.getWidth(null)),
                            String.valueOf(img.getHeight(null)),
                            System.getProperty("os.name")
         return MessageFormat.format(HEADER, params);
     public static int[] convertImageToIntArray(Image img)
         if (img == null)
             return null;
        int imgResult[] = null;
        try
            int nImgWidth = img.getWidth(null);
            int nImgHeight = img.getHeight(null);
            if (nImgWidth < 0 || nImgHeight < 0)
                Trace.traceError("Image is not ready");
                return null;
            Trace.traceInfo("Image size: " + nImgWidth + "x" + nImgHeight);
            imgResult = new int[nImgWidth*nImgHeight];
            PixelGrabber grabber = new PixelGrabber(img, 0, 0, nImgWidth, nImgHeight, imgResult, 0, nImgWidth);
            grabber.grabPixels();
            ColorModel model = grabber.getColorModel();
            if (null != model)
                Trace.traceInfo("Color model is " + model);
                int nRMask, nGMask, nBMask, nAMask;
                nRMask = model.getRed(0xFFFFFFFF);
                nGMask = model.getRed(0xFFFFFFFF);
                nBMask = model.getRed(0xFFFFFFFF);
                nAMask = model.getRed(0xFFFFFFFF);
                Trace.traceInfo("The Red mask: " + Integer.toHexString(nRMask) + ", Green mask: " +
                                Integer.toHexString(nGMask) + ", Blue mask: " +
                                Integer.toHexString(nBMask) + ", Alpha mask: " +
                                Integer.toHexString(nAMask));
            if ((grabber.getStatus() & ImageObserver.ABORT) != 0)
                Trace.traceError("Unable to grab pixels from the image");
                imgResult = null;
        catch(Throwable error)
            error.printStackTrace();
        return imgResult;
     public static Image convertIntArrayToImage(Component comp, int imgData[], int nWidth, int nHeight)
         if (imgData == null || imgData.length <= 0 || nWidth <= 0 || nHeight <= 0)
             return null;
        //ColorModel cm = new DirectColorModel(32, 0xFF0000, 0xFF00, 0xFF, 0xFF000000);
        ColorModel cm = ColorModel.getRGBdefault();
        MemoryImageSource imgSource = new MemoryImageSource(nWidth, nHeight, cm, imgData, 0, nWidth);
        //MemoryImageSource imgSource = new MemoryImageSource(nWidth, nHeight, imgData, 0, nWidth);
        Image imgDummy = Toolkit.getDefaultToolkit().createImage(imgSource);
        Image imgResult = comp.createImage(nWidth, nHeight);
        Graphics gc = imgResult.getGraphics();
        if (null != gc)
            gc.drawImage(imgDummy, 0, 0, nWidth, nHeight, null);
            gc.dispose();
            gc = null;
         return imgResult;
     public static boolean saveImageToStream(OutputStream out, Image img, String sImageName)
         boolean bResult = true;
         try
             ObjectOutputStream objOut = new ObjectOutputStream(out);
            int imageData[] = convertImageToIntArray(img);
            if (null != imageData)
                // Now that our image is ready, write it to server
                String sHeader = getImageDataHeader(img, sImageName);
                objOut.writeObject(sHeader);
                objOut.writeObject(imageData);
                imageData = null;
             else
                 bResult = false;
            objOut.flush();
         catch(IOException error)
             error.printStackTrace();
             bResult = false;
         return bResult;
     public static Image readImageFromStream(InputStream in, Component comp, StringBuffer sbImageName)
         Image imgResult = null;
         try
             ObjectInputStream objIn = new ObjectInputStream(in);
             Object objData;
             objData = objIn.readObject();
             String sImageName, sSource;
             int nWidth, nHeight;
             if (objData instanceof String)
                 String sData = (String) objData;
                 int nIndex = sData.indexOf(' ');
                 sImageName = sData.substring(0, nIndex);
                 sData = sData.substring(nIndex+1);
                 nIndex = sData.indexOf('x');
                 nWidth = Math.atoi(sData.substring(0, nIndex));
                 sData = sData.substring(nIndex+1);
                 nIndex = sData.indexOf(' ');
                 nHeight = Math.atoi(sData.substring(0, nIndex));
                 sSource = sData.substring(nIndex+1);
                 Trace.traceInfo("Name: " + sImageName + ", Width: " + nWidth + ", Height: " + nHeight + ", Source: " + sSource);
                 objData = objIn.readObject();
                 if (objData instanceof int[])
                     int imgData[] = (int[]) objData;
                     imgResult = convertIntArrayToImage(comp, imgData, nWidth, nHeight);
                     sbImageName.setLength(0);
                     sbImageName.append(sImageName);
        catch(Exception error)
            error.printStackTrace();
         return imgResult;
     }

While testing more, I found that the client side is generating color UI screens if I use JDK 1.3 JVM for running the server (i.e the side that generates the img) without changing single line of code. But if I use JDK 1.1.8 JVM for the server, the client side is generating black and white versions (aka gray toned) of UI screens. So I added code to save int array that I got from PixelGrabber to a text file with 8 ints for each line in hex format. Generated these files on server side with JVM 1.1.8 and JVM 1.3. What I found is that the 1.1.8 pixel grabber is setting R,G,B components to same value where as 1.3 version is setting them to different values thus resulting in colored UI screens. I don't know why.

"Extend a Wireless Network" seems to be... broken?

Hey guys,
Here's the scoop.
I have one Airport Extreme 802.11n that's connected to a cable modem. It's set to "Create a Wireless Network". It's at 5 GHz, and "Allow this Network To Be Extended" is checked. It works fine!
I have another Airport Extreme 802.11n upstairs that's set to "Extend a Wireless Network". I've then entered the network name and password of the original network. It successfully connects just fine to #1, and gets an IP address.
Then, I wander about.
When I get poor signal from the original base station (#1), and I enter the range of the extender station (#2), the laptop switches over to #2 and the network COMPLETELY DROPS OUT.
I.e., I can ping 10.0.1.1, but I cannot access the internet, no web pages can be loaded, etc. I'm stuck -- Airport is dead and I have to power down #2 and reboot.
Has anybody tried using two 802.11n Airport Extremes in this kind of configuration? With both set to 5GHz 802.11n only, and one sharing, the other extending?
If so.. what's your secret? Or is this just a striaght-up bug?
Thanks, Cabel
PS: Don't forget, this has nothing to do with WDS.

Hey guys,
Here's the scoop.
I have one Airport Extreme 802.11n that's connected
to a cable modem. It's set to "Create a Wireless
Network". It's at 5 GHz, and "Allow this Network
To Be Extended" is checked. It works fine!
I have another Airport Extreme 802.11n upstairs
that's set to "Extend a Wireless Network".
I've then entered the network name and password of
the original network. It successfully connects just
fine to #1, and gets an IP address.
Then, I wander about.
When I get poor signal from the original base
station (#1), and I enter the range of the
extender station (#2), the laptop switches over to
#2 and the network COMPLETELY DROPS OUT.
I.e., I can ping 10.0.1.1, but I cannot access the
internet, no web pages can be loaded, etc. I'm stuck
-- Airport is dead and I have to power down #2 and
reboot.
Has anybody tried using two 802.11n Airport
Extremes in this kind of configuration? With both
set to 5GHz 802.11n only, and one sharing, the other
extending?
If so.. what's your secret? Or is this just a
striaght-up bug?
I have the same identical configuration EXCEPT that I am not using 5GHz. Works beautifully. 100% coverage on 3 floors of my house.

Not able to connect remote oracle database over VPN

I can not connect remote oracle database over VPN. tnsping is ok and it shows the server information of remote database. i can also telnet the 1521 port of remote database server. I can connect the same server when it is located in the same LAN. Please help me out this is very urgent.

6b6c669e-6baa-45c4-a6dc-444aef2d5e7a wrote:
I can not connect remote oracle database over VPN. tnsping is ok and it shows the server information of remote database. i can also telnet the 1521 port of remote database server. I can connect the same server when it is located in the same LAN. Please help me out this is very urgent.
First, this is a forum of volunteers. There is no "urgent" here.
"Urgent" means one of two things -
1) people are dying, or
2) you have a customer-facing, revenue-producing production system that is down.
(And to get some perspective on the second case, keep the first in mind.)
For the first, you call whatever civil emergency service seems appropriate.
For the second, you open an SR with Oracle - which requires a paid-up support contract. For *them* to consider your problem "urgent", you will need to demonstrate that your problem falls under item #2. I seriously doubt your problem fits that criteria.
You don't have a support contract? Now you know the exact dollar figure that your company places on the data.
That said, you need to understand a few things about your specific problem,
First, port 1521 is only used by the listener to accept a connection request. Once it gets that request (and finds that it is for a service (sid) that it knows about, it will fork a server process and tell the requesting client that it can communicate with that server process over some other port .. a randomly chosen port number in the "high" range. It could be your vpn is blocking that other port, whereas your internal firewall is not.
But this is just an educated guess since I cannot find "can not connect remote oracle database over VPN" in any error message manual. If you had mentioned the VPN along with an actual oracle error message we could be much more precise in our diagnoses and recommendations.
---- edit 22 Sep
It occurred to me that I just assumed you were using the same client machine in both cases ... a laptop that you use both at work (local network) and home (vpn). If that assumption is false, there are probably problems with your tns setup on the home (vpn) machine.
But again, it would be much easier to help if you gave us an actual error message.

What is the best way to extend a Wireless network?

Hi,
We have 3 devices,
1) Our Primary Network Router (which creates our office Network and has DHCP enabled).
2) We have and Airport Extreme, which is used to create our Wireless Network (THIS IS SET TO “Create Wireless Network”), it has DHCP Enabled, its DHCP IP Scheme is set to 192.168.2.x, where the IP Scheme of our Primary Network is set to 192.168.181.x.
3) We have an Airport Express that we are trying to use to EXTEND our Wireless Network.
The most important thing we are trying to accomplish is to isolate the Wireless Network from our Primary Network, so Wireless Clients can access the Internet, but CAN’T SEE or ACCESS the Shared Network Volumes AVAILABLE ON THE PRIMARY NETWORK.
At the moment, the Wireless Clients can access the Internet and receive an IP in the range of 192.168.2.x from the DHCP Server in the Airport Extreme. That part of it is working, but the Wireless Clients can unfortunately still SEE and ACCESS the Network Volumes available on the Primary Network. WHICH IS NOT WHAT WE WANT!!
Question 1: How can we have the Airport Create a separate Network, so the Wireless Clients CAN’T SEE or ACCESS the Network Volumes from the Primary Network, but can still get access to the Internet through the Primary Network?
Question 2: What is the best way to use the Airport Express to “EXTEND” the Airport Extreme’s Wireless Network? I have tried WDS “Main” for Extreme and WDS “Remote” for Express, but all that doesn’t allow you to use the Extreme to Create a Separate Network, it uses the DHCP Server built into the Primary Network’s Router. Also tried to set the Express to “EXTEND WIRELESS NETWORK”, which seems to work, but I am not sure why. Because I don’t have a cable from the Extreme to the Express, which is sounds like you have to when it is setup that way!!
Any help would be greatly appreciated!!
Thanks
Kalagan

Question 1: How can we have the Airport Create a separate Network, so the Wireless Clients CAN’T SEE or ACCESS the Network Volumes from the Primary Network, but can still get access to the Internet through the Primary Network?
There is no way to do this. Any of the wireless clients of the AirPort Extreme base station (AEBS) can see any device connected to the AEBS's WAN port. Clients of a subnet can see anything on the supernet.
You could configure you network like this:
Internet-> (WAN) AEBS (LAN) -> Primary router
As long as the Primary router was providing DHCP/NAT the things on the LAN side of the Primary router would be hidden from the AEBS clients.
A better solution may be to have 2 completely separate networks OR invest in some type of network security firewall device to actively isolate your Primary network.
Question 2: What is the best way to use the Airport Express to “EXTEND” the Airport Extreme’s Wireless Network? I have tried WDS “Main” for Extreme and WDS “Remote” for Express, but all that doesn’t allow you to use the Extreme to Create a Separate Network, it uses the DHCP Server built into the Primary Network’s Router. Also tried to set the Express to “EXTEND WIRELESS NETWORK”, which seems to work, but I am not sure why. Because I don’t have a cable from the Extreme to the Express, which is sounds like you have to when it is setup that way!!
WDS is 802.11g's method of wirelessly extending a network.
"Extend wireless network" is 802.11n's method of wirelessly extending a network.
Neither of them require the AirPort Express (AX) to be cabled to the AEBS.

How many Airport devices do I need to extend an existing network?

Hello all,
I hope one of you might be able to help me with a problem.
I recently just moved to a different apartment, and my router (from my local internet provider) does not reach to all the rooms in the apartment.
Since I also wanted to stream wireless music in my home office I read that the Airport express would be a great solution to both extend the existing network and stream wireless from my Apple products.
I went to buy the Airport express, and asked the guy in the local authorized reseller of Apple products, if I could use this without connecting it via cables to my router (hence using it via wifi only). And he said yes, which I believed. However, after trying to set it up, and failed. I started searching for questions about my issue.
So:
Do I need two airport devices if I want to extend my existing network, when the router is in the living room, and the speakers that I want to stream from are located in my home office in the other end of the apartment? The area that I want to extend the existing network to is the bed room, next to the office.
So I thought that I could set the Airport express up in my office and connect it to the mini-jack from the speakers, and voila it would just do as I wanted to. But since I'm not a technical expert, I might have misunderstood, and I really do not want long ethernet cables running all over the place.
Is the only solution then to buy two devices? (Oh and for your information, I am not able to move the router to the office since there is no outlet for the internet, the only place it can be set up is in the living room).
Hope someone can help enlighten me on this issue. Thank you :-)

You need two AirPorts if you want to wirelessly "extend" the network, which will provide more wireless coverage....since both AirPorts will be broadcasting a wireless network.
You only need one AirPort Express if all that you want to do is use it for AirPlay to pick up the wireless signal and "join" your existing wireless network. In order to do this, the Express must be able to receive a good wireless signal from your router.
To test if you have a good signal, take a laptop or mobile device to the area where you want to install the AirPort Express and check to make sure that you can get a good wireless connection at that location. If you can, then the AirPort Express should work well at the same point.

How to extend a wifi network of third party router with TC 4th generation?

After searching the communities for a while, I did not find a definitive answer on the following question:
- I recently bought a 4th generation Time Capsule 2TB (MD0322/A), that I also want to use as an extension for our existing wifi network.
- This wifi network is maintained by a Sitecom Wireless 300N XR Gigabit Router. Router is set to work over 2.4 GHz (B+G+N) because of several non-N-wifi devices in the network. The channel in use is currently 11.
- This router provides so called WDS functionality, i.e. the ability for other wifi access points to act as a seamless extension of the basic wifi network (using the same SSID).
- The security settings in the router are WPA2 Mixed, with a password in plain ASCII.
- There seems to be no way to set different security levels for WDS-connections versus normal AP (access point) connections. If WDS is enabled, the security settings of the AP-mode are extended to the WDS connection.
I have set the Sitecom router to enable WDS, and added the MAC-address of the TC in the configuration of this router.
When configuring the Time Capsule, with Airport Utility 5.5.3, I can select the option to use TC to extend an existing network, and I can select the network of choice using the WPA personal or WPA/WPA personal security. However, the TC does not succeed in extending the network, and reports this back. If I manually configure the TC and select the network of choice, Airport Utility reports back that the selected network cannot be extended.
I have read several times in other posts that Time Capsule can only connect to third party routers via WDS using WEP-authentication, but these posts were quite old. I was wondering if this is still the case, or that Apple has updated this functionality in newer versions of TC, and thus there could exist a trick to connect to a WDS using WPA.
I really would appreciate suggestions
Bram Bos

gilles13 wrote:
I have a mac and pc (win7) both are connected thru a network with wifi and allready two access pt.
Airport can not be used to extend a WiFi created by a non-Apple box.
You need to turn off the radio in the router (shut down the existing WiFi). Purchase TWO Airport Express units. Connect one to the router with an Ethernet cable. Configure that one as your primary WiFi network and then use the second Express as the extender.
You need to locate the second Express where it receives a decent WiFi signal. Too far away and it has nothing to extend. Too close and it doesn't buy you anything. Before you plug in the second Express, check to see where the primary WiFi disappears completely. My personal WAG is that you want to locate the second Express 2/3 the distance to that point.
If you use Airport Utility to configure the units, it's a snap. In fact, if you configure the primary first and the extender second, AU will default to exactly the settings that you want.
By the way, I refereed to the Express because it's less expensive than the Extreme and you didn't indicate any need for the Extreme features.

How do I use airport express to extend my wireless network?

How vcan I extend the range of my wireless network using Airport Express?

It appears that you may have "join a wireless network" and "extend a wireless network" mixed up a bit.
The Express can "join" virtually any wireless network produced by any manufacturer's router if it is provided with the correct settings:
name of the wireless network
the correct wireless security settings
and correct password.
"Join" is normally used for AirTunes or to connect a USB printer to the Express for remote printing.
But, the Express does not provide any additional wirless coverage when it "joins" another wireless network.
Apple's "Extend a wireless network" feature, which was introduced about 5 years ago, allows the Express to connect to another Apple "n" wireless router and then "repeat" or "extend" the wireless signal....providing more wireless coverage in the area where the Express is located.
This is a proprietary setting. Apple says it will not work with devices from other manufacturers. To our knowledge, this is correct.
Prior to 2007, Apple used a setting called WDS to allow the Express to be configured to provide more wireless coverage. Attempts were made by a number of manufacturers to standardize the WDS settings, but things were never finalized.
The result is that Apple's older "b/g" routers were sometimes compatible with WDS settings from another manufacturer. There were a handful of products....5 or 6, as I recall....that were said to work. Some did, some didn't. Linksys had a couple of models, Netgear had one, SMC another, etc. Extremely limited.
Since WDS was never adopted as an industry standard, manufacturers developed their own WDS settings. Compatibility was extemely limited and unreliable. That continues to this day with WDS.
Bottom line....It is always best to stick with the same manufacturer throughout your network as far as routing is concerned.
If you have an newer "n" Apple router like an AirPort Extreme, the Express can extend the wireless as can along Extreme. If your Extreme is dual band, and you want to extend both bands, then you need another Extreme.
Another responder suggested to someone that they could connect the AirPort Express to a router via Ethernet. What exactly would that achieve?
That is a completely different subject since this discussion is about extending a wireless network using wireless only.

How can I extend a wireless network with my AirPort Extreme Base Station?

Today I purchased a brand new, dual-band base station to replace my Belkin N router, as I have had a handful of firewall, coverage, and other networking problems in my house lately. First off, I really like this router and it was very easy to setup. My MacBook Pro could use both bands and established a 300 Mbit/s link very quickly. After tweaking various settings to my liking, I was also able to maximize the connections on many of my non-Apple machines and devices. I noticed that the range of its network was better than my Belkin's, but unfortunately, it failed to completely saturate the area sufficiently. Since the Belkin still works well enough, I was hoping I could bridge them together one way or the other.
The Belkin router does not support any bridge mode that I know of, but the AirPort Extreme should be able to join a wireless network and then extend that over WiFi and Ethernet, correct? I would like to place them at opposite ends of my home so I can get strong WiFi signals everywhere inside. However, when I try to get the base station to connect to my preexisting WiFi connection, it tells me that I can't extend the network and fails to join.
So is this possible? And if it is, how would I go about setting it up? I know it would probably be easier if I had a simple range booster such as an AirPort Express, but I didn't buy one while I was at Fry's since I hoped I could make use of the older Belkin. This is its product page, if needed. Thanks for any suggestions.
-MacUser

The Belkin router does not support any bridge mode that I know of, but the AirPort Extreme should be able to join a wireless network and then extend that over WiFi and Ethernet, correct?
Sorry, but no. The AirPort Extreme Base Station cannot "join" a network like the AirPort Express or Time Capsule, but you wouldn't want to do this anyway because in this configuration these devices will only perform as wireless clients ... not routers.
Instead, the AirPort Extreme can either be extended or can extend another 802.11g or 802.11n AirPort ... or a very very few non-AirPort devices.
One option for your Belkin would be to connect it to the AirPort Extreme by Ethernet but this may not meet your requirements or be a desirable situation. Otherwise, you would need to get another AirPort to extend your current one.

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