Multi-protocol payment switch

muNSwitch

One platform for card and digital payment switching. Where conventional switches were built around a single protocol and bolted on digital payments afterwards, muNSwitch treats ISO 8583 card traffic and UPI/QR payments as first-class, native workloads — and runs the mirror issuer-host role on the same engine.

Payment network diagram: POS/card terminal, online checkout, mobile UPI/QR, security/HSM and issuer/host all connecting through the muNSwitch core
25,500+ TPS
Absorbs peak seasonal and promotional volume
<15 ms
Inside every scheme's response-time window
99.99%
Target uptime
1M+
Concurrent sessions
Platform components

Three functional layers, one shared core

The acquiring and issuing engines never talk to a network directly. Both go through the same shared core, and every component is independently deployable and independently scalable.

Acquiring

Terminal & checkout ingress

Accepts transactions from physical terminals and the online checkout entry point, identifies the card and transaction type, and routes each one toward the correct network.

Acquiring

3-D Secure authentication

For online transactions, runs cardholder authentication before authorization — including handling a step-up challenge when the issuer requires one.

Acquiring

Authorization & persistence

One shared sequence for both entry points: record the transaction before it leaves the building, dispatch it, record the outcome, and trigger a reversal automatically if the outcome is ever ambiguous.

Shared core

Routing engine

Decides which network owns a given transaction, using the card number range and transaction type, and hands it to that network's own connection and message format.

Shared core

Network message translation

Converts a transaction into and out of each network's exact wire format — field layout, numeric encoding, message framing — one translator per network, added without disturbing any other network's traffic.

Shared core

Direct network API adapters

For networks reachable by a modern REST API rather than a legacy socket connection, a parallel path handles authentication, request signing and response mapping over HTTPS.

Issuing

Issuing listener

Accepts inbound authorization requests arriving from a card network, one connection per network, each with that network's own message format and framing.

Issuing

Authorization decision service

The system that decides approve, decline or refer. The issuing side hands off the decoded transaction and encodes whatever decision comes back — momentPay Shield, or your existing host.

Cross-cutting

HSM, monitoring & config

A hardware security module protects PINs and keys, dashboards track health and volume, and each network's connection details and message format live in configuration rather than a rebuild.

Two ways in

Genuinely different protocols, one pipeline

DimensionCard presentCard not present
Entry pointPhysical POS terminal or card readerHosted payment page, called from a merchant checkout
Message formatISO 8583 — a fixed, bitmap-driven binary layoutJSON, defined by each network's own REST API
TransportA persistent TCP socket per network, with that network's framingHTTPS, secured with mutual TLS
Cardholder authenticationChip & PIN, or signature, at the point of sale3-D Secure — a browser or app-based challenge

Both entry points build the same internal transaction record and run through the same authorization, persistence and reversal pipeline.

Protocol coverage

Payment support matrix

Payment typeProtocolSupport levelBusiness value
Credit / debit authorizationISO 8583Full nativeProcess or stand behind cards on any connected scheme
Reversal & network managementISO 8583Full nativeKeeps state consistent when a message times out or a connection drops
UPI / QR digital paymentsNPCI UPI 2.0Full nativeReal-time digital payments alongside card traffic
Direct-network RESTJSON / RESTExtensible frameworkA path for schemes moving from TCP to modern APIs
International messagingSWIFT / ISO 20022On the roadmapA path to global issuer messaging

ISO 8583 card processing

Full EMV chip support, contactless readiness, multi-currency handling and intelligent network routing.

UPI digital payments

NPCI-certified processing, dynamic and static QR code generation, and real-time settlement.

Modern API support

RESTful APIs, GraphQL for flexible queries, WebSocket for real-time updates, webhook event notifications.

Deployment patterns

Three ways customers come to muNSwitch

Greenfield deployment

A new business sets up muNSwitch as its first switch: cloud deployment, network certifications and go-live typically inside three to four weeks.

Legacy replacement

An existing switch is analysed, muNSwitch is stood up in parallel, and traffic migrates gradually before the legacy platform is decommissioned.

Capability extension

The existing switch stays in place for what it already does well, and muNSwitch is added specifically to bring in UPI, QR or other digital protocols under one dashboard.

Common questions

What evaluators ask

Not necessarily. The protocol engine's authorization step is pluggable, so muNSwitch can call momentPay's own risk engine, momentPay Shield, or your existing authorization service through a defined integration contract.

Yes. The acquirer switch, issuer bridge and protocol engine scale and deploy independently, so you can bring UPI online after card processing is already live, or the other way round.

Migration runs in parallel with your existing switch first, with transactions reconciled between both systems before any traffic is cut over, so nothing is migrated blind.

Deployment location and data residency are configurable according to the on-premise, hybrid or cloud-native deployment model you choose.

Additional nodes join the cluster and load-balance automatically, so scaling up is an infrastructure change rather than an architectural one.

Benchmark muNSwitch against your own volumes

Bring a rough profile of current volumes and peak concurrency, the networks you need, and your preferred deployment model. We will run a proof of concept with sample transactions and share load-testing results against your requirements.