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Best way to tunnel RMI over HTTP

I'm looking for a secure way to tunnel RMI traffic.
In My application(java Webstart) i must assume that the only port that is open is port 80.
I have the looked att socketfactories for rmi but do i really need a proxy then.
I need to do all my tunneling on the client side.
The only firewall i am trying to get past is on the client side.
I'm not able to open 1099 with port ranges above.
Would be nice to see some implementations.
Thanks!

Port 1099 was reserved for RMI at IANA in about 1995. There is no reason for it not to be open for outbound access in the client-side firewall.
RMI can be made to use fixed port numbers by supplying a port number when constructing (super(port)) or exporting (exportObject(object, port)). Better still, if you create the Registry within the server JVM via LocateRegistry.createRegistry(), all subequently exported remote objects will use that port unless they specify a different port or they use a server socket factory.
BUT ... RMI already includes HTTP tunneling 'out of the box'. No external solution required. You have to deploy the RMI-Servlet provided with the JDK, at the server end.

(a)
although not the newest fashion, exposing remote services with Hessian and Burlap seems to be a simple solution to avoid problem working across firewalls: http://hessian.caucho.com/doc/
see sample code for the server and client side:
http://www.javatpoint.com/spring-remoting-by-hessian-example
(b) or consider using Spring HttpInvokder (see some sample code here: http://www.javatpoint.com/spring-remoting-by-http-invoker-example)
HttpInvokder provides more customization options through the RemoteInvocationFactory, RemoteInvocationExecutor and HttpInvokerRequestExecutor strategies (for example, to add custom context information (such as user credentials) to the remote invocation, or using java’s built-in object serialization etc.), see:
http://docs.spring.io/spring-framework/docs/2.0.x/api/org/springframework/remoting/support/RemoteInvocationFactory.html

Simulating slow/lossy communication in java

I need to test a functionality internal to my company's server whose benefit is evident only when clients run slow (as of latency and packet loss). To that extent, I need to simulate clients on a slow and/or lossy connection (TCP/HTTP). I'm using a Mac, Mountain Lion, and ideally I'd need to run both server and client locally.
One approach I tried to pursue -- unsuccessfully -- was to get hold of some java APIs that allow me to build clients with slow connections. I know JMeter has got something called SlowSockets (or something similar), but I was looking for APIs more focused on slow-performing clients. Any ideas of useful APIs?
Another approach I tried consisted in using a proxy to act as a middleman between client and server. In that case, the proxy should provide functionalities for simulating slow links. I've tried Charles proxy (Mac) and Apache TCPMon, however I seem to miss something when I try to get them at work. With TCPMon, for instance, when I start it in 'Proxy' mode (which is the mode that offers the 'simulate slow link' functionality) I define port for the local proxy, but I can't see how to define the remote host and port. Something similar happens with Charles Proxy; I can set the local port in the Proxy settings, but I can't understand how to define the remote end of the proxy (in fact connections fail saying the remote server is not responding). Anyone having ideas what I'm doing wrong?
One further approach I have tried to pursue is by using lower-level (e.g. OS-based) means; in this case, I tried Apple's Network Link Conditioner. I switched it on and defined my slowness parameters, but when I ping I don't seem to see the expected RTT etc. I've got a feeling NLC has a tight relationship with XCode and iOS testing, anyone capable of putting it at work for testing other (e.g. Java) applications? I've also tried ipfw on Mac, however the manual says ipfw is now deprecated and I don't want to dedicate time to get to know a tool that won't be available soon.
Any idea/help will be highly appreciated.
Thanks in advance.

chat application, sockets vs RMI

I want to build a chat application and am confused about deciding whether to use sockets or RMI to build the application. I have heard that RMI is difficult to configure and deploy over the Internet, since that is my intention I was wondering what would be more appropriate to go with, sockets or RMI. Also is it easier to solve issues because of NAT in sockets or RMI ?
What if I want to add voice support at some later point, does it help deciding which way to go ?

1. For applications like Chat Messenger, my bet will be on Sockets.
2. RMI will be an over kill here.
3. Moreover NAT issue is not about Socket or RMI, its about Static IPs.
4. If you want to deploy a Chat Server over the net, then first you must have a Static IP, you need to have to ask your ISP to provide you with one of them at extra cost, or there are sites over internet, that makes your dynamic ips as static.
5. But if your server is locally located in a LAN environment, then i think you won't have a problem in doing it.

Both are reasonable choices that could be used to build a chat server/client. A socket can be set up to take incoming connections and start a new thread for each "chatter" alternatively RMI can be used to create a distributed object on which the client can call methods.
RMI is basically a layer over sockets often used in distributed computing where some transparency is needed and remote methods need to be called. It also allows for stateless connections to the server.
If you choose to implement the server in RMI just be warned that thread safety may be an issue.
For a local server it is probably easier to use pure sockets.
For more details on RMI:
http://www.oracle.com/technetwork/java/javase/tech/index-jsp-136424.html

socket-over-ssh factory

I would like to use some JMS (Java Message Service) library, ActiveMQ or FFMQ, but need to run it over SSH protocol. I have started implementing my own connection factory method of ActiveMQ, but then the idea of implementing Socket/SocketFactory interfaces over SSH has struck me. It would let me adapt pretty much any JMS implementation without really touching its code. As usual, somebody has already had this idea and I have found couple implementations of this approach.
http://svn.apache.org/repos/asf/pig/trunk/lib-src/shock/org/apache/pig/shock/SSHSocketImplFactory.java
http://benkstein.net/java/SSHSocketFactory/javadoc/
The first one is a class somewhere in the guts of Apache Pig. The second is a hack/addon for MySQL client, published by Frank Benkstein in 2004. It appears that MySQL community was not interested in it (http://www.webservertalk.com/archive277-2004-7-294282.html).
I wonder if there are other implementations of SocketOverSsh factory, possibly better documented/supported?
Update: My primary motivation is to avoid having additional open ports or configuration changes both on the client and the server. So SOCKS or plain port forwarding are not desirable solutions.

This looks a bit heavy-weight. Have you considered finding a solution using the SOCKS protocol? An ssh-client can act as a SOCKS proxy by e.g. invoking it with "ssh -D ". The good thing is that the JVM already knows how to use SOCKS automatically for network connections. Of course the cave-at is that the ssh-connection would be established outside of the Java app.

Java Socket Programming behind proxy

I have written a TCP IP socket program which works fine.
But my socket program did not work if my server or client is behind proxy.
So how to overcome from this type of issue.
Thanks
Bapi

Well there's two issues to consider:
Behind a proxy; and
Behind a firewall.
Firewall tends to be easier: you simply use port 80 (HTTP) or 443 (HTTPS). Proxy is harder because direct network communication tends to be disabled from normal PCs.
This is why you often find people using HTTP and/or SSL as their transport mediums because they bypass these kinds of security issues. You can do push content (with long-lived connections aka Comet techniques) so there's typically no real technical reason not to.
But it's hard to say one way or the other if that's a good idea or not without knowing more about your application and any pertinent requirements.

Proxies usually work at the application level, not at the transport level.
Here is some information about Java and proxies.

Depending on the proxy, there may be little that you can do. If the Proxy is designed to block all traffic that it does not directly handle, then you have to either go through the proxy, somehow working with it, or you have to find a way to sneak through the proxy.
For example, many applications are built on top of HTTP precisely because it is commonly allowed through firewalls and is commonly proxy-friendly. Thus, it's a pretty safe way of communicating when you know that you'll be installing the application in environments where proxies may exist.
In your case, it depends on what port(s) your application uses, on whether these ports are commonly handled by a proxy for any existing protocol, on whether or not you're using a standard (commonly known) protocol or have invented your own, and so on.
Is this proxy a transparent proxy? (That is, do web browsers have to be configured to see it, or not?) The kind of proxy it is determines part of how your application needs to work with it. Is the proxy controlled by your organization?
You say you are using port 5018. Just as an experiment, can you try using port 80? Just because you're using port 80 doesn't mean you have to use HTTP. This is worth a try to see if it helps.