Network & Node Security Flashcards
7 cards from real Blockchain Technology practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Network & Node Security flashcards as text
What is the main goal of a BGP hijack targeting blockchain infrastructure?
Answer: Reroute node traffic to partition or intercept it
BGP hijacking misdirects internet routing to isolate or intercept a node's traffic.
Which measure helps a node resist network-partitioning (routing) attacks?
Answer: Connecting over multiple ISPs/ASes and using encrypted, authenticated links
Path and provider diversity plus authenticated encryption make routing-level interception harder.
A node operator wants to hide the node's IP to reduce targeted attacks. Which approach is appropriate?
Answer: Route P2P traffic through Tor or a VPN
Anonymizing transports like Tor or a VPN obscure the node's real address from attackers.
Why is time synchronization (NTP) security relevant to node operation?
Answer: Manipulated time can disrupt consensus timing and block validation
Many consensus rules depend on accurate clocks, so NTP manipulation can cause rejected or invalid blocks.
What is a recommended practice for securing a node's SSH administrative access?
Answer: Key-based auth, disabled root login, and restricted source IPs
Key-based auth with restricted access greatly reduces the risk of administrative compromise.
An attacker replays old, valid network messages to a node to confuse its state. What protection counters this?
Answer: Nonces, timestamps, and session sequence numbers
Anti-replay mechanisms like nonces and sequence numbers ensure each message is fresh and unique.
Why should node logs be shipped to a separate, secured log server?
Answer: To preserve forensic evidence even if the node is compromised
Off-host logging protects audit trails from being erased by an attacker on the node.