Abstract: In response to receipt of a request message from a requester, a reply message is created. The reply message includes a message identifier of the request message copied from the received request message. The reply message is published to each of a group of replicated message queues. The reply message is identifiable by the requester using the copied message identifier of the request message on any one of the group of replicated message queues prior to being consumed by the requester.

Abstract: In response to receipt of a request message from a requester, a reply message is created. The reply message includes a message identifier of the request message copied from the received request message. The reply message is published to each of a group of replicated message queues. The reply message is identifiable by the requester using the copied message identifier of the request message on any one of the group of replicated message queues prior to being consumed by the requester.

Abstract: In response to receipt of a request message from a requester, a reply message is created. The reply message includes a message identifier of the request message copied from the received request message. The reply message is published to each of a group of replicated message queues. The reply message is identifiable by the requester using the copied message identifier of the request message on any one of the group of replicated message queues prior to being consumed by the requester.

Abstract: In response to receipt of a request message from a requester, a reply message is created. The reply message includes a message identifier of the request message copied from the received request message. The reply message is published to each of a group of replicated message queues. The reply message is identifiable by the requester using the copied message identifier of the request message on any one of the group of replicated message queues prior to being consumed by the requester.

Abstract: In response to receipt of a request message from a requester, a reply message is created. The reply message includes a message identifier of the request message copied from the received request message. The reply message is published to each of a group of replicated message queues. The reply message is identifiable by the requester using the copied message identifier of the request message on any one of the group of replicated message queues prior to being consumed by the requester.

Abstract: In response to receipt of a request message from a requester, a reply message is created. The reply message includes a message identifier of the request message copied from the received request message. The reply message is published to each of a group of replicated message queues. The reply message is identifiable by the requester using the copied message identifier of the request message on any one of the group of replicated message queues prior to being consumed by the requester.

Abstract: In response to receipt of a request message from a requester, a reply message is created. The reply message includes a message identifier of the request message copied from the received request message. The reply message is published to each of a group of replicated message queues. The reply message is identifiable by the requester using the copied message identifier of the request message on any one of the group of replicated message queues prior to being consumed by the requester.

Abstract: In response to publication of a topic message on a topic to a messaging system by a publisher application, a determination is made as to whether any subscriber applications are registered for the topic. In response to determining that at least one subscriber application is registered for the topic, the published topic message is delivered to each registered subscriber application. In response to determining that no subscriber applications are registered for the topic, the published topic message is stored and in response to receipt of a first subsequent subscription request from a new subscriber application for the topic, the stored published topic message is delivered to the new subscriber application.

Abstract: In response to receipt of a request message from a requester, a reply message is created. The reply message includes a message identifier of the request message copied from the received request message. The reply message is published to each of a group of replicated message queues. The reply message is identifiable by the requester using the copied message identifier of the request message on any one of the group of replicated message queues prior to being consumed by the requester.

Abstract: A publish/subscribe messaging network in which a distributed set of publish/subscribe brokers comprises a first subset of publish/subscribe brokers, each arranged to store proxy subscription information for the whole of the distributed set of brokers; and a second subset of publish/subscribe brokers, each configured to send subscription information for local subscribers to one or more brokers within the first subset of publish/subscribe brokers, and configured to request, from a broker within the first subset of brokers, proxy subscription information following receipt of a message.

Abstract: Disclosed is a method comprising steps of: a broker software application receiving a first published message on a topic from a publisher application and storing the first published message in a local storage location along with an indicator which indicates that the first published message originated from a publisher application that is local to the broker software application; the broker software application receiving a second published message on the topic from another broker software application and storing the second published message in the local storage location in place of the previously stored first published message, along with an indicator which indicates that the second published message originated from a publisher application that is remote to the broker software application; and the broker software application delivering the second published message, from the local storage location, to a requesting subscriber application which has requested a last retained publication message on the topic.

Abstract: In response to publication of a topic message on a topic to a messaging system by a publisher application, a determination is made as to whether any subscriber applications are registered for the topic. In response to determining that at least one subscriber application is registered for the topic, the published topic message is delivered to each registered subscriber application. In response to determining that no subscriber applications are registered for the topic, the published topic message is stored and in response to receipt of a first subsequent subscription request from a new subscriber application for the topic, the stored published topic message is delivered to the new subscriber application.

Abstract: When a new broker is connected to a network, a loop detection message is sent over the new connection created by the new broker. The loop detection message includes topics. At each receiving broker, topics that cannot be propagated to a neighbor broker are removed. If the loop detect message contains no topics, the loop detect message is not propagated further. If the loop detection message returns to the new broker, a loop is detected.

Abstract: When a new broker is connected to a network, a loop detection message is sent over the new connection created by the new broker. The loop detection message includes topics. At each receiving broker, topics that cannot be propagated to a neighbor broker are removed. If the loop detect message contains no topics, the loop detect message is not propagated further. If the loop detection message returns to the new broker, a loop is detected.

Abstract: Disclosed is a method comprising steps of: a broker software application receiving a first published message on a topic from a publisher application and storing the first published message in a local storage location along with an indicator which indicates that the first published message originated from a publisher application that is local to the broker software application; the broker software application receiving a second published message on the topic from another broker software application and storing the second published message in the local storage location in place of the previously stored first published message, along with an indicator which indicates that the second published message originated from a publisher application that is remote to the broker software application; and the broker software application delivering the second published message, from the local storage location, to a requesting subscriber application which has requested a last retained publication message on the topic.

Abstract: A publish/subscribe messaging network in which a distributed set of publish/subscribe brokers comprises a first subset of publish/subscribe brokers, each arranged to store proxy subscription information for the whole of the distributed set of brokers; and a second subset of publish/subscribe brokers, each configured to send subscription information for local subscribers to one or more brokers within the first subset of publish/subscribe brokers, and configured to request, from a broker within the first subset of brokers, proxy subscription information following receipt of a message.