Server-initiated
resolution
Any resolver stage may initiate back-end stages
–Like a
recursive computation (think DNS)
–Server-initiated
resolution is “horizontal”
•Simplest two-stage
example: web proxy
–Proxy, as browser
target, talks to real target
–In reverse proxy, id-a
real target, not URLa
2. URLa
1. initiate
6. display
browser
User
5. URLb
proxy
server
real
server
3. id-a
4. id-b