quartz/content/notes/25-network-security-2.md

title	aliases	tags
25-network-security-2		cosc203 lecture

TLS

• security protocol above transport layer.

  • supported by most browsers
  • prvides, confidentaility, integrity, authentication

• replaced SSL

• provides API that any application can use

• 

• QUIC and http3: moves transpor tlayer functions to app layer, on top of UDP

how

• handshake: use certificates, private keys to authenticate each other, exchange or create shared secret
• key derivation: use shared secret to derive set of keys
• data transfer: as a series of records, not just one time transactions
• connection closure: special message to close message

protocols

• handshake protocol
• changechipherspec protocol
  • choose encryption algerithms
• alert Protocol
  • terminate
  • error reporting
• record protocol
  • divide data to segments
  • encrypt and authenticate and send

handshake

• 

cryptographic keys

• bad to use the same key for more than one crytographic algorithm (encryption and authentication)
• uses master secret
• 

IPSec

firewall

IDS