1. 4byte ASNs Test Scenarios - 8th TWNIC OPM 2007/7/5, Taipei kae@du.net.tw

2. Agenda http://www.seed.net.tw 4 bytes AS number overview BGP capability in 4 bytes AS number BGP attribute update New BGP attribute Testing scenarios Reference 2

3. 4 bytes AS number overview http://www.seed.net.tw Original ASN encoded 2 bytes ASN pool: 0 ~ 65535 ASN expansion 4 bytes ASN pool: 0 ~ 4294967295 M:N M: 0 ~ 65535 N: 0 ~ 65535 2 bytes map to 4 bytes 0.0 ~ 0.65535 3

4. BGP capability in 4 bytes AS number http://www.seed.net.tw BGP Capability Advertisements RFC2842 Capabilities Optional Parameter BGP router supported 4 bytes ASN Capability code: 65 Capability Length: 4 4

5. BGP attribute update http://www.seed.net.tw AS_PATH attribute update Original: AS carried in this attribute is encoded as a 2 byte ASN New: AS carried in this attribute is encoded as a 4 byte ASN 5

6. BGP attribute update http://www.seed.net.tw AS_AGGREGATOR attribute update Original: AS carried in this attribute is encoded as a 2 byte ASN New: AS carried in this attribute is encoded as a 4 byte ASN 6

7. New BGP attribute http://www.seed.net.tw AS4_PATH Optional transitive attribute AS_PATH is well-known mandatory attribute AS4_PATH semantics: AS carried in this attribute is encoded as a 4 bytes entity 7

8. New BGP attribute http://www.seed.net.tw AS4_AGGREGATOR Optional transitive attribute AS_AGGREGATOR is optional transitive attribute AS4_AGGREGATOR semantics: AS carried in this attribute is encoded as a 4 bytes entity 8

9. Testing scenarios http://www.seed.net.tw NEW AS_PATH testing Peering with 4 bytes ASN is mappable to 2 bytes ASN 0.65000 0.65001 Peering with 4 bytes ASN is NOT mappable to 2 bytes ASN 0.65000 2.65001 9

10. Testing scenarios http://www.seed.net.tw AS4_PATH testing Peering with 4 bytes ASN is mappable to 2 bytes ASN 65000 0.65001 Peering with 4 bytes ASN is NOT mappable to 2 bytes ASN 65000 2.65001 10

11. Testing scenarios http://www.seed.net.tw AS4_PATH testing 2 bytes ASN travel through 4 bytes ASN 65000 0.65001 65002 65000 2.65001 65002 11

12. Testing scenarios http://www.seed.net.tw AS4_PATH testing 4 bytes ASN travel through 2 bytes ASN 0.65000 65001 0.65002 2.65000 65001 2.65002 12

13. Testing scenarios http://www.seed.net.tw NEW AS_AGGREGATOR testing 0.65002 0.65000 0.65001 0.65003 13

14. Testing scenarios http://www.seed.net.tw AS4_AGGREGATOR testing 2 bytes ASN is aggregated via 4 bytes ASN 65002 65000 2.65001 65003 14

15. Testing scenarios http://www.seed.net.tw AS4_AGGREGATOR testing 4 bytes ASN is aggregated via 2 bytes ASN 2.65002 0.65000 65001 2.65003 15

16. Reference http://www.seed.net.tw RFC1771 Y. Rekhter, T. Li, A Border Gateway Protocol 4 (BGP-4), March 1995. RFC4893 Q. Vohra, E. Chen, quot;BGP Support for Four- octet AS Number Spacequot;, May 2007. BGP support for 4-Byte AS Numbers - Implementation Survey Report Geoff Huston, Asia Pacific Network Information Centre 16

17. Questions & Comments? sees your needs