I talked to Tim in the JBoss Messaging IRC channel to get some quick answers about the flaws of R2 protocol. They were: * Connection pooling doesn't allow you to send other commands when a request is in progress. It also causes the order of invocation get mixed up. - This issue can be fixed by fixing R3 client behavior. * The way ping works - I don't have much idea about how ping works. Someone could address this issue. * Protocol doesn't have a command type identifier - It's OK because we can bump up the version field and provide a command type identifier, sequence no, etc if necessary. Also, he suggested me to abandon R2 protocol and go straight to the whole new transport (e.g. SSH + new wireformat) because: * We are not required to be backward compatible with R2 and we should give it up to avoid maintenance difficulty. * We can run both R2 and R3 at the same time in the microkernel, so R2 users should be able to keep using R2 services or upgrade to R3. I think it makes fair amount of sense (or perhaps I am missing something big :)) except that I have no idea if it's OK for all users. It might be OK to do so considering that most users are other JBoss projects. WDYT? View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4166886#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...