Network Communication and Protocol Layers BDC Practice Questions (Page 5)

Questions 21–25

1. 21application · medium

   A developer is explaining to a client how blockchain nodes communicate. The client asks why a transaction sent to one node eventually reaches all nodes. Which explanation is accurate?

   • AThe receiving node broadcasts the transaction to its peers, who then rebroadcast it to their peers until all nodes have it.
   • BThe transaction is broadcast only to miners, who then include it in a block that is sent to all nodes.
   • CThe transaction is sent directly to every node by the originating client.
   • DThe transaction is stored in a central database that all nodes query.
   Reveal Solution Discussion Select an answer first
2. 22expert · hard

   A blockchain network is forking frequently because some nodes receive blocks faster than others. The developer must reduce the fork rate while maintaining decentralization. Which approach is most balanced?

   • AReduce the number of nodes to speed up communication
   • BUse a centralized block producer to eliminate forks
   • CIncrease the block size to reduce the number of blocks
   • DOptimize block propagation with relay networks and compact blocks
   Reveal Solution Discussion Select an answer first
4. 23foundation · easy

   How do blockchain nodes achieve a consistent view of the shared state?

   • ABy periodically downloading a snapshot of the state from a trusted third party
   • BBy each node independently validating all transactions and blocks and following the consensus rules
   • CBy synchronizing only the most recent block and discarding historical data
   • DBy relying on a central authority to broadcast the final state to all nodes
   Reveal Solution Discussion Select an answer first
5. 24application · medium

   A blockchain startup is deploying a private Ethereum network for a consortium of banks. They want to ensure that only authorized nodes can join and that transaction propagation is efficient. Which combination of mechanisms should they implement?

   • APublic DNS seed lists and flooding every transaction to all nodes
   • BCentralized relay server that forwards all transactions to every node
   • CRandom peer selection with no authentication and periodic full sync
   • DStatic node lists with permissioned enode IDs and gossip-based propagation
   Reveal Solution Discussion Select an answer first
6. 25expert · hard

   A developer is designing a blockchain for a remote area with intermittent internet connectivity. Nodes frequently disconnect and reconnect. Which peer management strategy best maintains network cohesion?

   • ADisconnect from all peers if any message is lost
   • BUse a single long-lived connection to a central relay node
   • CMaintain a persistent list of known peers and attempt reconnection with exponential backoff
   • DRequire nodes to rediscover peers from scratch after every disconnect
   Reveal Solution Discussion Select an answer first