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School of Computer Science & Engineering
University of New South Wales
 Advanced Operating Systems 
 COMP9242 2002/S2 

The Return of the Dumb Terminal: SLIM[SLN99]

Problem: high cost-of-ownership of PCs

• PCs are expensive to maintain/administrate as individual machines.
• Would be cool to have the power of a big iron occasionally.
  • There's still (or again?) some attraction in big central servers.

Idea: Stateless thin-client architecture

• Stateless (other than frame buffer) cheap terminals (graphic displays),
• server sends 2D bitmaps,
• connected via 100Mbps ethernet.

Supported by very simple, low-level display protocol (5 commands):

1. SET: set pixes in rectangle to literal value
2. BITMAP: fill rectangle with foreground, background colour
3. FILL: set all pixels to fixed value
4. COPY: copy rectangle
5. CSCS: colour-space conversion

Benchmarked GUI apps: photoshop, netscape, framemaker, MPEG, quake