Caesar: a Content Router for High Speed Forwarding Matteo Varvello, Diego Perino, Jairo Esteban (Bell Labs, Alcatel-Lucent)

1. Caesar: a Content Router
for High Speed Forwarding
Matteo Varvello, Diego Perino, Jairo Esteban
Bell Labs, Alcatel-Lucent
CCNxCon2012, September 13th,2012, Sophia Antipolis
COPYRIGHT © 2011 ALCATEL-LUCENT. ALL RIGHTS RESERVED.

2. Forwarding Information Base
FIB performs component-wise longest prefix matching Interest names
- e.g. ccnx://BellLabs/ICN/talks/reality.avi/chunk0 (B=5 components)
• Hardware-based approaches (TCAM)
• Software-based solution
- Multi-bit tries
- Bloom filter
SRAM Bloom filters
DRAM
RLDRAM Prefix hash-table
COPYRIGHT © 2011 ALCATEL-LUCENT. ALL RIGHTS RESERVED.

3. AGENDA
Rationale
Design
Evaluation
What s next?
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4. Rationale
Longest Prefix Match (LPM) should be as much independent as
possible from the length of content names
Number of components, and character per component
Distribute the forwarding table across line cards to maximize size
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5. Design – LPM – Distributed Bloom Filters (DLB-BFs)
IPv6 Lookups using Distributed and Load Balanced Bloom Filters for 100Gbps Core Router Line Cards. Haoyu Song, Fang Hao, Murali S.
Kodialam, T. V. Lakshman INFOCOM 2009
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6. Design – LPM – Distributed Bloom Filters (DLB-BFs)
K DLB-BFs independently of the prefix length
Map each content prefix to K bits, independently of the number of
characters per component
Perform B*K hash functions in parallel
Dimension system for high Bmax*K (hardware limits)
Avoid slow LPM for long content names via prefix expansion
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7. Design – Distributed Packet Processing
h(comp1)modN
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8. Results – Single Line card
Xilinx Virtex-6 and NetFPGA 40G board ; Bmax=128, T=64
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9. Results – Whole Router
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10. What s next?
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11. Questions?
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12. Forwarding Information Base
FIB performs component-wise longest prefix matching Interest names
- e.g. ccnx://BellLabs/ICN/talks/reality.avi/chunk0 (B=5 components)
Hardware-based approaches (TCAM)
Software-based solution
- Multi-bit tries
- Bloom filter
SRAM Bloom filters
DRAM
RLDRAM Prefix hash-table
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COPYRIGHT © 2011 ALCATEL-LUCENT. ALL RIGHTS RESERVED.

13. 66Mps = half of the LPM operation
rate performed today by each line
card of a core router
10 Milion prefixes=2% of today s
globally unique and routable
hostnames
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14. Numerical Evaluation
Reference design is Xilinx Virtex-6 and NetFPGA 40G board
On-chip memory
34Mbit with up to 1,064 2-port SRAM blocks (32Kbit)
Off-chip memory
216Mbits SRAM
2.3Gbit RLDRAM
We divide the 1,064 2-port SRAM blocks across 8 DLBBFs
Each DLB-BF is composed by 64 SRAM blocks (64Kbit)
A 2-port SRAM block stores the LT
We generate 128x8=1,024 hash functions
Bmax=128,T=64
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15. Design – Linecard Details
If(B>Bmax)
Prefix Expansion
h(comp1)modN ;
h=CRC-64
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16. Conclusions
FIB design is a challenge for Information-Centric Networking
We design Caesar, a Content Router for High Speed
forwarding
Distributed packet processing
LPM implemented with distributed Bloom filters
On-going and future work
Hardware implementation
Extension to software router
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17. Named Data Networking – Content Router
• CS (Content Store) is the same as buffer memory of an IP router but can
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store a Data packet after it has been forwarded (caching).
• PIT (Pending Interest table) keeps track of forwarded Interests. Only one
entry per similar requests is kept.
• FIB (Forwarding Information Base) is used to forward Interest packets
toward potential sources using LPM lookup.
A Reality Check for Content Centric Networking. Diego Perino and Matteo Varvello ICN2010 (Also published in CCR, October 2011)
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COPYRIGHT © 2011 ALCATEL-LUCENT. ALL RIGHTS RESERVED.

18. Forwarding Information Base
FIB performs component-wise longest prefix matching Interest names
- e.g. ccnx://BellLabs/ICN/talks/reality.avi/chunk0 (B=5 components)
• Hardware-based approaches (TCAM)
• Software-based solution
- Multi-bit tries
- Bloom filter
SRAM Bloom filters
DRAM
RLDRAM Prefix hash-table
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COPYRIGHT © 2011 ALCATEL-LUCENT. ALL RIGHTS RESERVED.