Common Message Switch (CMS)
The current CMS infrastructure will be supported for AEMI. Members may continue to send orders via CMS to AEMI or to a broker booth for manual handling on the floor. Execution reports will be returned to the member firm via CMS.

Financial Information eXchange (FIX)
Amex will make available a FIX gateway for member firms that wish to connect to FIX. Orders may be sent by member firms to AEMI or to broker booth for manual handling on the floor. Execution reports will be returned to the member firm via FIX. New order types (electronic crosses in the first instance and any other new order types going forward) will be made available to FIX users.

Amex Application Programming Interface (API)
An API will be offered to on-floor Specialists and Market Makers. Member firms will have the choice of using the API for full functionality or just for streaming quotes and offering electronic price improvement. Please read the AEMI Connectivity FAQ for additional information.

Service Bureaus
Members may connect to AEMI via a service bureau's CMS or FIX connections.

FAQs

Will market making be permitted off-floor?
There is no change to current regulations, which require Market Makers to be physically present on the trading floor in the crowd in order to quote and trade.

What are the differences between using CMS and using FIX?
The differences between orders being sent using CMS or directly using FIX are twofold. First, FIX customers should notice considerably faster turnaround times compared with CMS, of up to one second roundtrip. Second, some features will be offered to FIX users only. For the initial rollout, this includes the six electronic cross order types, Hit or Take orders, and manually handled order types with specific execution instructions which are directed to the booth (Not Held, Prospectus, 144, 145, Company Buyback). The Intermarket Sweep Order (ISO) is the only new order type that will be offered to CMS users.