ExhibitS ExhibitLSI1 A AS 65501ISPB AS 65502Advertised Prefixes: 172.

Local preference is a BGP attribute that dictates which path is preferred when multiple paths to the same destination are available. A higher local preference is preferred over a lower one. Since ISP A (AS 65501) is advertising a local preference of 100 and ISP B (AS 65502) is advertising a local preference of 200 to AS 65512, traffic from devices in AS 65512 will prefer the path via ISP B for all networks that ISP B advertises. However, since ISP A advertises the 172.20.21.0/24 network and ISP B does not, traffic for 172.20.21.0/24 will go through ISP A. For the 172.20.0.0/24 network, which both ISPs advertise, devices in AS 65512 will prefer the path via ISP B due to the higher local preference.