Is there a size limit on substrate messages?

Question

So, substrate uses a bunch of network messages like block announce, grandpa message, block request-response, transaction. Substrate has notification substream open sending and receiving these messages and may be some other data as well. I expect that there might be some limit on size of the data substrate receives, because otherwise people can send huge amount of data to do DoS. So, is there a size limit on these network messages and how much? For more context, look at https://github.com/ChainSafe/gossamer/issues/2399

Answer 1

Different subprotocols are using different limits:

• request/response protocols: 16MB (blocks, state, light, warp)
• notifications: grandpa 1MB, transactions 16MB, block announcements 1MB