The Need for Traceback
 
 
- Internet hosts are vulnerable
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- Many attacks consist of very few packets
- Fraggle, Teardrop, ping-of-death, etc.
 
- Internet Protocol permits anonymity
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- Attackers can ėspoofî source address
- IP forwarding maintains no audit trails
 
- Need a separate traceback facility
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- For a given packet, find the path to source