A fire-district IT team wants outbound traffic to prefer ISP-A and wants return traffic from the Internet to prefer the ISP-B path for the same civic prefixes. Which attribute pairing matches those goals?

A fire-district IT team that wants outbound traffic to prefer ISP-A while wanting Internet return traffic to prefer ISP-B for the same civic prefixes must use different tools for each direction. Raising local preference for paths learned from ISP-A influences the fire district’s outbound exit choice because local preference is evaluated early inside the AS. Influencing return traffic requires changing how the prefixes look to the outside—commonly AS-path prepend on advertisements toward ISP-A (making ISP-A’s path less attractive inbound) and/or preferential advertisements toward ISP-B—so remote ASes prefer ISP-B to reach the civic prefixes. That pairing matches outbound versus inbound traffic-engineering goals. MED alone setting both outbound exit choice and inbound return preference identically in every AS overstates MED: MED is optional, often compared only within the same neighboring AS, and does not replace local preference for outbound exit selection inside the fire district. Weight on ISP-B plus Origin incomplete on ISP-A forcing identical inbound and outbound results mixes a local-only Weight (outbound on that router) with Origin and does not reliably engineer return paths. Claiming AS-path prepend toward ISP-A and local preference toward ISP-B always swap both directions the same way confuses which attribute affects which direction. Exam caveat: local preference = inside outbound preference; AS-path prepend / MED / communities = common inbound-influencing tactics; neither attribute alone controls both directions universally. Operational check: set higher local pref for ISP-A-learned paths and confirm outbound exit with traceroute/show ip bgp; apply prepend toward ISP-A (or preferential ads toward ISP-B); validate external preference via looking glasses or ISP feedback for return path.