<html><head><style type='text/css'>p { margin: 0; }</style></head><body><div style='font-family: Arial; font-size: 12pt; color: #000000'>One thing I would like to add to the discussion, which I was thinking about yesterday.<br><br>Our customer base has grown substantially, and the type of customer we are now engaging with have much larger deployments than in the past. I continue to here complaints about those customers ability to move from one major EAP release to another. We also have a specific customer that made us commit to having our JMS client remain compatible across major releases (EAP 5 JMS client can talk to an EAP 6 server, and an EAP 7 server too). I know of another customer that has complained about remote EJB calls in the past, in this regard as well. With these large deployments it becomes very difficult to a "big bang" upgrade, and they need to ability to have old clients talk to new servers.<br><br>So, with the design of this, it would be great to take into account this need. I'm just thinking that if there ends up being a need for the wire protocol to change in the future, that we would need to still be able to support the older clients.<br><br>Andy<br><br><hr id="zwchr"><blockquote style="border-left: 2px solid rgb(16, 16, 255); margin-left: 5px; padding-left: 5px; color: rgb(0, 0, 0); font-weight: normal; font-style: normal; text-decoration: none; font-family: Helvetica,Arial,sans-serif; font-size: 12pt;"><b>From: </b>"David M. Lloyd" <david.lloyd@redhat.com><br><b>To: </b>jboss-as7-dev@lists.jboss.org<br><b>Sent: </b>Tuesday, October 18, 2011 7:43:50 PM<br><b>Subject: </b>Re: [jboss-as7-dev] Clustered invocation design<br><br>Great. We're now officially moving forward with #2. I am not <br>addressing automatic connection management at this time; it will be the <br>user's responsibility to establish connections for now. We can revisit <br>our options once we're up and running.<br><br>On 10/18/2011 08:07 PM, Jason Greene wrote:<br>> I think 2 is the only realistic option since it supports distant remote clients. It's also similar to what we had before. Async topology changes shouldn't be an issue IMO. The server endpoint always has the option to redirect to the right location. As long as we have the requirement that the server endpoints be a jgroups cluster, then we can reuse the jgroups view IDs which have already formed a consensus.<br>><br>> Another interesting aspect is stateless load balancing policy and stateful session affinity. Since time is short my thoughts are start basic: round robin + sticky failover.<br>><br>> Sent from my iPad<br>><br>> On Oct 18, 2011, at 9:31 AM, Jaikiran Pai<jpai@redhat.com> wrote:<br>><br>>> From someone who has very limited knowledge of clustering internals -<br>>> the only "advantage" (for us) in going with #1 would be the ability to<br>>> setup easy connectivity? From what I understand, #2 would allow more<br>>> flexibility to the users (and a bit of complexity for us in managing the<br>>> connections and authentication) on setting up the cluster for the<br>>> invocations. Am I right?<br>>><br>>> -Jaikiran<br>>> On Tuesday 11 October 2011 09:29 PM, David M. Lloyd wrote:<br>>>> There are at least two basic paths we can follow for clustered<br>>>> invocation based on the current architecture. The right choice is going<br>>>> to depend primarily upon the expected use cases, which I am not in a<br>>>> position to properly judge.<br>>>><br>>>> Option 1: Clustered Invocation Transport<br>>>> ----------------------------------------<br>>>><br>>>> In this option, we introduce a new "LAN" transport type for invocation<br>>>> on the cluster. The transport would use direct TCP connections or UDP<br>>>> messages (or both, depending on request size) to convey the invocation.<br>>>> The characteristics of this option are as follows:<br>>>><br>>>> - Security: reliance on physical network security only (no TLS or<br>>>> authentication)<br>>>> - Latency is very low, even to new nodes<br>>>> - Topology changes can be conveyed as separate asynchronous messages<br>>>> - Invocations from external networks would happen through a proxy node,<br>>>> with Remoting being bridged to the LAN, to perform security functions<br>>>><br>>>> Option 2: Load-balanced Remoting Connections<br>>>> --------------------------------------------<br>>>><br>>>> In this option, we rely on the client to establish one or more Remoting<br>>>> connection(s) to one or more of the nodes of the cluster. Logic in the<br>>>> client will be used to determine what connection(s) to use for what<br>>>> clusters. We have the option of automatically connecting as topology<br>>>> changes or requiring the user to set up the connections in advance.<br>>>> Note that automatic connection cannot work in the case of<br>>>> user-interactive authentication. Characteristics:<br>>>><br>>>> - Security: full authentication and TLS supported<br>>>> - Latency is low once the connection is established, however there is<br>>>> some overhead involved in authentication and security negotiation<br>>>> - Topology changes should be asynchronous notifications<br>>>> - Each connection has to be separately authenticated<br>>>> - Automatically establishing connections is not presently supported, so<br>>>> we'd need a bit of infrastructure for that. Deal with user-interactive<br>>>> authentication. Deal with connection lifecycle management. Deal with<br>>>> configuration. This will be a point of fragility<br>>>><br>>>> Summary<br>>>> -------<br>>>><br>>>> For both options, we have to determine an appropriate load-balancing<br>>>> strategy. The choice of direction will affect how our clustering and<br>>>> transaction interceptors function. We also have to suss out the logic<br>>>> around dealing with conflicting or wrongly-ordered topology updates;<br>>>> hopefully our existing policies will continue to apply.<br>>>><br>>><br>>> _______________________________________________<br>>> jboss-as7-dev mailing list<br>>> jboss-as7-dev@lists.jboss.org<br>>> https://lists.jboss.org/mailman/listinfo/jboss-as7-dev<br>><br>> _______________________________________________<br>> jboss-as7-dev mailing list<br>> jboss-as7-dev@lists.jboss.org<br>> https://lists.jboss.org/mailman/listinfo/jboss-as7-dev<br><br><br>-- <br>- DML<br>_______________________________________________<br>jboss-as7-dev mailing list<br>jboss-as7-dev@lists.jboss.org<br>https://lists.jboss.org/mailman/listinfo/jboss-as7-dev<br></blockquote><br></div></body></html>