We are looking at applications of PubSubHubbub that are mission critical for businesses. So while businesses will tolerate some level of variable delivery delay, they won't tolerate downtime. They are used to 100% or near 100% (five nines) type reliability.
Does PubSubHubbub have support for any type of load distribution, load balancing, or fault tolerance? For example, what appears to be a single hub to the outside world really consists of several servers that share the load, and that keep the hub up and running even if one of the servers stops working. Or, if the load to capture the publisher's source info backs up, is there some mechanism to share the load out? I can see firms listing multiple hubs instead of one in thinking that this somehow provides for greater reliability, but I'm not sure that does anything but create multiple feeds that subscribers then have to true up. Thoughts?
