02 / ROUTING

ROUTING IS INFRASTRUCTURE.

Every payment does not need to take the same path. Design rules around payment context, geography, availability and your processing strategy.

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HOW IT WORKS

RULES. PATHS. FAILOVER. TRACE.

01 / RULES

Routing rules are evaluated in priority order.

Each rule combines transaction attributes — currency, issuer country, card brand, amount band, authentication outcome — and resolves to a target route. The first matching rule wins; unmatched traffic falls through to a default route rather than failing.

ROUTING TABLE / MERCHANT_EUILLUSTRATIVE

PRI	CONDITION	TARGET	FALLBACK
10	issuer_country = "TR" AND window = OPEN	TURKEY_PRIMARY	EU_PRIMARY
20	currency = "USD" AND issuer_country = "US"	US_PRIMARY	GLOBAL_USD
30	currency IN ("EUR","GBP")	EU_PRIMARY	EU_SECONDARY
99	default	GLOBAL_USD	—

02 / PATHS

A route is a path, not just an acquirer.

A route resolves to a specific connector and merchant account (MID) behind it. Separating the rule from the path means a connector can be swapped or rebalanced without rewriting every rule that points to it.

ROUTE / US_PRIMARYILLUSTRATIVE

RULE 20matched
ROUTEUS_PRIMARY
CONNECTORACQUIRER_US_01
MIDMID_US_01
NETWORKcard scheme

03 / FAILOVER

When a path degrades, the next eligible path is defined in advance.

Failover can be configured on connector health or specific response classes — timeouts, processor unavailability — but not on issuer declines, where a retry on another rail rarely changes the answer and can damage acquirer relationships.

FAILOVER POLICYILLUSTRATIVE

TRIGGER	ACTION
connector timeout > 8s	retry on fallback route
route_health = UNAVAILABLE	switch to fallback before attempt
issuer decline (05, 51)	return to merchant — no retry
soft decline (3DS required)	challenge, then same route

04 / DECISION TRACE

Every decision is recorded with the rule that made it.

Operations can answer "why did this payment go there?" from the trace alone — which rules were evaluated, which matched, and which health state was in effect at that moment.

DECISION TRACE / PAY_AG_8J29LILLUSTRATIVE

+0 msrule 10 evaluated — issuer_country ≠ TRskip

+1 msrule 20 matched — USD / USOK

+1 msroute US_PRIMARY health = HEALTHYOK

+2 msconnector ACQUIRER_US_01 selectedOK

NEXT STEP

BUILD THE RIGHT
PAYMENT PATH.

Let's discuss the infrastructure your business needs.

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