Rename private method isOtherOutdated to isOtherDifferent

[patriknw]

Caused confusion for someone reading the code.

[netcomm]

thanks for the quick reply.I still have some question, I detail described:
for example there have two nodes: node_a, node_b;
#1 if node_a Update some value(say gCounter_a) on time1, the value's digest is updated;
#2 node_a generate a GossipTick on time2, then send 'Status' msg to node_b;
#3 node_b corresponding value's(gCounter_a) digest is old, then node_b in the 'isOtherOutdated' function case 'Some(digest) if digest != otherDigest ⇒ true', and then send it's current "older" gCounter_a back to node_a in a 'Gossip' msg.
#4 node_a recieve 'Gossip' msg and do something ... ...
maybe in this position node_b just send nothing to node_a, or get 'Gossip' msg from node_a?
if i lose something,please point out, thanks all!

[patriknw]

Thanks for clarification. Your understanding is correct. When node_a receives the gossip msg in #4 it will merge with local value and the local value will win (as it is newer). Nothing is sent back to node_b at that point.

The new value will be spread when some other node (e.g. node_b) sends status to node_a.

It would be possible to send back when receiving gossip message. That would speed up dissemination, at the cost of sending more data. I will consider doing that.

I don't want to add causality information in the status message, because that means version vectors and that takes up a lot more space than a digest.

Thanks for feedback.

[patriknw]

Fixed this in #30, including sending back gossip message