User Enters Query

1
User Enters Query
Formulate Queries
Lycos
Yahoo
Excite
Download References
Collate Results
Remove Duplicates
Post-Process Results
Yes
Download Results?
No
Output Results to User
2
User Interface
Application
Server Interface
Aggregation Engine
Key
External Unit
Module
API Boundary
3
I/O Layer
OS Layer
4
MetaCrawler Architecture
Server Interface
Client Interface
Parse Events
End user
API Requests
Wrappers
Harness
Search Client
Search Events
Application
I/O Interface
Cache Manager
Net Manager
Other Protocols
Remote Site
DataBase
Local Storage
API Boundary
Module
External Entity
5
Connect www.foo.com
Send GET /index.html
Receive ltdatagt
Close
6
Connect DNS
Send www.foo.com
Receive 123.1.2.3
CloseDNS
Connect 123.1.2.3
Send GET /index.html
Receive ltdatagt
Closewww.foo.com
7
0
1
2
3
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