Why was QUIC created?
To reduce handshake latency and eliminate TCP head of line blocking.
Why does QUIC run over UDP?
UDP allows user space reliability and avoids TCP delays.
What is TCP’s head of line blocking problem?
Loss on one stream blocks all streams.
How does QUIC avoid HOL blocking?
Independent streams with separate delivery.
What are QUIC connection IDs used for?
Demultiplex flows and support migration.
What is a 1-RTT QUIC handshake?
Full crypto handshake + resumption ticket.
What is a 0-RTT QUIC connection?
Client sends encrypted early data immediately.
What is advantage of 0-RTT?
Zero round trips before sending data.
What is risk of 0-RTT?
Replay attacks.
What does QUIC build on top of UDP?
Reliability retransmission ordering flow and congestion control.
One major benefit of QUIC over TCP?
Much faster connection establishment.
One disadvantage of QUIC?
Higher CPU cost and encrypted headers hinder routers.
