Thanks for the reply.
I read IPLD, and also tried IPNS & pubsub. Let me introduce the difficulty I encountered more specifically.
The problem is how to lookup an always-changing content using a constant ID.
E.g. to build a distributed blog using IPFS. Adding new blog article could be mapped to IPFS add operation. Then how to list all the article index, using something constant?
IPNS could be helpful. But update of the article index is triggered by distributed clients. One solution could be making the specific IPNS private key open, so any client could do the update. That could lead to even more issues, e.g. conflict of update.
What's the best practice to handle such requriement?