Naming

• Name spaces and directories
• DNS architecture
• Security issues with DNS
• DNSSEC, DANE

Name spaces

DNS

DNS namespace

DNS has a hierarchical namespace

• ■ First level managed by the Internet Corporation for Assigned Names and Numbers (ICANN)
• ■ Authority over other levels is delegated: Second level generally managed by registrars, further levels managed by organizations or individuals
• ■ Result: Each domain owns its own names

DNS security

DNSSEC

Security Extensions

Digital Signature

Akamai

CDN

Geolocation

• How does Akamai know which servers are ‘close’ to a client?
• This is done via geolocation
  • Essentially, a mapping of IP address to physical locations
  • “158.130.54.11? That machine is in Philadelphia, close to 34th and Walnut!”
• How are these maps built?
  • Simple version could use triangulation based on pings from different servers
  • The reality is a LOT more complicated!