ION's Fidessa FIX network and Quazar answer the same buy-side question, how do we connect to our brokers, with opposite models. ION operates a hosted, broker-neutral FIX network bundled with the Fidessa trading platform: ION hosts the solution, and clients reach the brokers already connected to it.1 Quazar, built by Quod Financial, is an AI-native FIX fabric that a firm downloads and runs itself, or has Quod Financial operate, connecting directly to each counterparty with no intermediary network. The choice is between using a hosted network and owning the connectivity layer.
ION describes its network as reaching over 6,500 buy-side customers and 600 brokers via FIX, with execution on more than 200 equities markets.1 Quazar is free for buy-side firms for up to 10 inbound connections and priced at a fixed rate for the sell side, and Quazar to Quazar connections between counterparties carry no network fee.
Quazar vs ION Fidessa at a glance
| Criteria | ION (Fidessa FIX network, FIX Connect) | Quazar |
|---|---|---|
| Category | Hosted, broker-neutral FIX connectivity and order-routing network, part of the Fidessa trading platform; FIX Connect is its client-connectivity layer1,2 | AI-native FIX fabric: routing, transformation, session management and monitoring in one platform |
| Who runs it | ION: "We host your solution, delivering high performance, lower infrastructure costs, and automated system upgrades"1 | Your firm, on-premise or cloud-hosted; or Quod Financial as a managed service |
| Where message data lives | On ION's hosted platform1 | In your deployment; message content is not transmitted to Quod Financial when you self-host |
| Path to a counterparty | Through the ION network; connection definitions are held as data in a directory of endpoints distributed across the network3 | Direct FIX session between your Quazar instance and the counterparty, or Quazar to Quazar |
| Commercial model | Part of the Fidessa platform and managed-service relationship; figures not published1 | Free for the buy side up to 10 inbound connections; fixed price for the sell side; no per-connection, plug-in or network fees |
| Onboarding | FIX Connect aims to let clients describe the connection they need and who they want to connect to, without the hosting platform changes previously required (ION, October 2021)4 | AI-generated rule sets from a counterparty's specification, template library, AI-driven automated certification and testing |
| Dialect translation and transformation | Not described on the ION pages reviewed2 | Core function: version conversion, tag remapping, defaulting, symbol suffixing, repeating-group manipulation, regulatory enrichment for Reg NMS, MiFID II and CAT |
| FIX versions | Not published on the pages reviewed2 | FIX 4.x and 5.0, with cross-version conversion inside a single flow |
| Monitoring | Not described on the pages reviewed2 | Grafana-based dashboards, latency tracking, alerting, audit trail, message-level tracing and replay |
| AI | None stated on the FIX connectivity pages reviewed2 | AI-native: rule generation, automated triage, automated certification; bring your own LLM; MCP for your own agents |
| Scale claims | Over 6,500 buy-side customers, 600 brokers via FIX, more than 200 equities markets (vendor page, undated)1 | No hard session limit by design; approximately 2,500 messages per second with full persistence enabled |
| Ownership | Fidessa acquired by ION Investment Group; deal agreed 20 April 2018, UK CMA clearance decision published 22 August 20185,6 | Built and maintained by Quod Financial, a trading technology company with more than twenty years of FIX infrastructure |
What is the ION Fidessa FIX network, and what does it do well?
Fidessa is an integrated multi-asset equities trading platform that ION acquired in 2018, in a deal agreed on 20 April of that year at £1.5 billion with the UK Competition and Markets Authority's clearance decision published on 22 August.5,6 Its FIX network is the connectivity layer of that platform: a hosted, broker-neutral network through which buy-side clients reach the brokers already connected to it, and through which brokers receive order flow from those clients. ION hosts the solution and handles infrastructure and upgrades.1
Its strength is reach. ION states that the network gives access to over 6,500 buy-side customers and 600 brokers via FIX, with execution on more than 200 equities markets.1 For a firm that already runs Fidessa, the network is part of the platform it uses every day, and a counterparty that is already on the network does not have to be connected from scratch. ION's FIX Connect programme, described in October 2021, set out to modernise that layer so that clients can describe the connection they need rather than wait for engineers to configure both ends.4
How does Quazar differ from a hosted FIX network?
Quazar differs from the ION network in where the connectivity layer sits and who controls it. With a hosted network, your order flow passes through the provider's infrastructure, your counterparties are the ones on that network, and the connection is a service you subscribe to. With Quazar, the fabric runs in your own environment or in a deployment dedicated to you: your OMS connects to Quazar, Quazar connects directly to each broker or venue over a standard FIX session, and message content stays within your deployment.
Two things follow. First, dialect translation is yours to configure rather than something the network does or does not do for you: Quazar rewrites each message into the receiving system's format using rules generated by AI from the counterparty's specification, and certifies the mapping with automated testing before cutover. Second, there is no intermediary network layer between your systems and your counterparties: when both sides run Quazar, they connect to each other directly. Buy-side firms run the full platform free for up to 10 inbound connections.
What Quazar does not give you is a pre-connected community. A hosted network's value is the brokers already on it; with Quazar, each counterparty is a session you establish, and the template library and automated certification are designed to shorten it. A firm that wants the network to have done the connecting is choosing a different model.
When is a hosted network the right choice, and when is Quazar?
A hosted network such as ION's suits a buy-side firm that runs the Fidessa platform, wants no connectivity infrastructure of its own, and is content for its order flow to pass through a third party. Quazar suits firms that want to own the layer: buy-side desks that want direct broker connections without an intermediary network, sell-side firms that need to normalise hundreds of inbound client dialects into one internal format, and any firm with data-residency requirements that prefers its messages never leave its environment.
The two can also coexist during a transition. Quazar sits between any FIX-enabled systems, so a firm can keep existing network connections in place and route new counterparties, or a specific asset class, through Quazar first.
Questions firms ask when comparing Quazar and ION Fidessa
Is Quazar a FIX network like Fidessa's?
No. ION's Fidessa FIX network is a hosted network you connect through. Quazar is software you run, or have Quod Financial run for you, that connects directly to each counterparty. There is no intermediary network.
Can Quazar replace ION FIX connectivity for a buy-side firm?
For the connectivity layer, yes: Quazar connects an OMS directly to brokers over standard FIX sessions, free for up to 10 inbound connections. It does not replace the Fidessa trading platform itself.
Does ION's network translate between FIX dialects?
The ION pages reviewed do not describe a transformation or normalisation capability. In Quazar, rule-based dialect translation, version conversion and regulatory enrichment are the core function.
Where does my order flow go with each option?
With ION, through ION's hosted platform. With a self-hosted Quazar deployment, messages are processed and stored in your own environment and are not transmitted to Quod Financial.
How do the commercial models differ?
ION's network is part of the Fidessa platform relationship, with no published figures. Quazar is free for the buy side up to 10 inbound connections and priced at a fixed rate for the sell side, with no network or per-connection fees.
Who owns Fidessa?
ION Investment Group, which agreed to acquire Fidessa Group Holdings plc on 20 April 2018. The UK Competition and Markets Authority published its clearance decision on 22 August 2018.
Sources
- ION Group, "Fidessa", iongroup.com/products/markets/fidessa/, accessed 22 September 2026.
- ION Group, "FIX Connect", iongroup.com/resource-center/markets/fix-connect/, accessed 22 September 2026.
- ION Group, "As connectivity gets more complex, new approaches are needed", iongroup.com/blog, accessed 22 September 2026.
- ION Group, "FIX Connect: technology of the future", 18 October 2021, iongroup.com/blog, accessed 22 September 2026.
- The Irish Times, "Ion Investment Group agrees £1.5bn deal to buy Fidessa", 20 April 2018, irishtimes.com, accessed 22 September 2026.
- UK Competition and Markets Authority, "ION Investment Group / Fidessa Group merger inquiry", decision published 22 August 2018, gov.uk, accessed 22 September 2026.
Quazar statements are taken from quazar.org product and FAQ pages and from Quod Financial's launch announcement of 16 September 2026, accessed 22 September 2026. FIX and the other terms used here are defined in the glossary. ION and Fidessa are trademarks of their owners; this page describes publicly stated capabilities and makes no claim about relative cost.