What is Lerian SLC?

Lerian SLC is your client-owned software for operating Nuclea’s Serviço de Liquidação Centralizada (SLC) — the ASLC engine, card roles, and multi-tenant model.

Lerian SLC is the client-owned software layer that operates the Serviço de Liquidação Centralizada (SLC) for a participant. The SLC is Nuclea’s centralized card-settlement messaging service. Lerian SLC runs inside the institution’s own regulated environment. It signs with the institution’s own ICP-Brasil certificate. It speaks the official ASLC message protocol to Nuclea (ISPB 29011780) over the RSFN, Brazil’s National Financial System Network.

Lerian SLC builds, signs, and transmits the ASLC settlement files. It correlates Nuclea’s returns. It tracks every operation through its settlement lifecycle by its NUliquid, Nuclea’s settlement identifier. Lerian SLC is standalone, multi-tenant, and API- and event-first.

What Lerian SLC does — and does not — do

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• It is standalone. Lerian SLC settles cards on its own and depends on no other Lerian product. Midaz and Reporter can consume Lerian SLC, but Lerian SLC does not depend on them.
• The private key never leaves the client’s custody. Lerian SLC materializes the unsigned file and delegates signing to a custody backend the client controls. Lerian never signs on the client’s behalf.
• It is multi-tenant from the ground up. One deployment serves many participants with full isolation.

Who it serves

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Lerian SLC serves the roles of the Brazilian card arrangement. A single deployment can act for one or several of them.

Role	What it is
Credenciadora (acquirer)	Captures card transactions from merchants and submits their settlement operations.
Subcredenciadora (sub-acquirer)	A participant that enables receiving merchants to accept payment instruments but does not act as creditor toward the issuer in settlement.
IF Domicílio	The domicile financial institution that receives settlement notices and credits the merchant.
IF Liquidante	The settling financial institution that funds the clearing position for a settlement cycle.
Bandeira	The card scheme of the arrangement.

Glossary

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Term	Meaning
Lerian SLC	Lerian’s client-owned software for operating Nuclea’s centralized card-settlement (SLC) messaging.
SLC — Serviço de Liquidação Centralizada	Nuclea’s centralized settlement service for the Brazilian card arrangement.
ASLC	The official Nuclea XML message layout family used by the SLC — UTF-16BE, XSD-validated.
NUliquid	Nuclea’s 21-position settlement identifier (an AAAAMMDD date prefix plus a sequence) that tracks each operation’s lifecycle.
ISPB	The BACEN participant identifier; Nuclea’s SLC destination is 29011780.
RSFN	Brazil’s National Financial System Network, which carries SLC traffic.
ICP-Brasil	The Brazilian public-key infrastructure whose certificate signs SLC files.
SPB security envelope	The BACEN payment-system envelope — GZIP plus an RSA/SHA-256 signature and AES-256, with a 588-byte security header — wrapping each file.
Clearing cycle	The settlement window over which Lerian SLC computes and reconciles positions for the IF Liquidante.

For how Lerian SLC sits alongside the other native rails and the partner interfaces, see Native messaging and partner interfaces. The card-domain deferred-net settlement family reaches Lerian SLC relayed from Lerian SILOC, the participant-side SILOC connectivity.