Aggressive - These orders are matched against existing Resting orders held in the order book. Once submitted these orders typically cannot be cancelled or modified.
Resting - These orders are submitted at price levels away from the prevailing market, i.e. buying at a price below or selling at a price above the market. Because the order will not be executed

Details of the TimeInForce values supported by Whisperer Enterprise for both categories are provided below.

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TimeInForce	Nature	Colloquial Name	Description
IOC	Aggressive	Immediate or Cancel	The Order must be executed immediately, at least in part (Partial fills are allowed), otherwise the Order is cancelled. AKA 'Fill and Kill'.
FOK	Aggressive	Fill Or Kill	The Order must be executed immediately, in full (no Partial fills), otherwise the Order is cancelled.
DAY	Resting	Day	The Order expires automatically on close of the trading day, if it is still unfilled.
GTC	Resting	Good 'Til Canceled	The Order remains active until it is either executed or cancelled. NOTE: Maximum possible duration is one trading week, but is equivalent to DAY for most Venues that reset daily.
GTD	Resting	Good 'Til Date	Order is active until a specified time. TWAP?
GFT	Resting	Good For Time	Order is active for a specified duration. TWAP?
OPN*		At Market Opening

Order Types

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There are three broad categories of OrderType:
Market - these are aggressive orders that are instructions to deal immediately at the best possible price. When buying, a market order will be filled at the currently prevailing Offer price; when selling, a market order will be filled at the currently prevailing Bid price.
Limit - these are resting orders visible to the market - hence the existence of Central Limit Order Book (CLOB) ECNs. they are instructions to deal if a market moves to a specific (more favourable) price or better. Limit orders remain open until they are either entirely filled, or the client submits an order
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cancel request, or the order expires.
Stop - these are resting orders that are not visible to the market and will activate once a specified Stop price has been met.

Details of the OrderType values supported by Whisperer Enterprise for all categories are provided below. or expire for GTD orders

Colloquial Name Description OrdType TimeInForce Venue Cancel on Disconnect?
Market An instruction to deal immediately at the best possible price (the current rate). Market DAY BME YES
Limit An instruction to deal if a market moves to a MORE favourable level. Limit DAY BME YES
Immediate Limit
Limit IOC BME, AGG N/A

Limit GTC AGG
Fill or Kill
Limit FOK BME N/A
Stop-Loss An instruction to deal if a market moves to a LESS favourable level. Stop Loss

Stop Loss GTC AGG
Stop Limit Executes an exposure-reducing limit order when market exceeds order's price. Stop Limit DAY
YES

Stop Limit GTC AGG
Stop-Trailing The Stop Price follows the market by a specified offset. Trailing Stop

Market Limit Order that starts as a Market order and executes any leaves quantity as a Limit order. Market With Leftover As Limit

Auction Price
Market OPN*
YES
Previously Quoted An order to hit an individual quote. To hit multiple quotes, aka sweeping, the user must submit individual orders from best to worst price. Previously Quoted
BME
VwapSweep An order that can hit/lift one or multiple quotes by submitting an order with the desired amount and the Volume Weighted Average Price (VWAP) of the total amount. VWAP Sweep
CitiCoLo
TWAP
Limit GFT/GTD

Attack

BME
Stop limit at rise Determined by Side?

BME
Stop limit at fall Determined by Side?

BME
Market Maker

BME
Limit Take Profit

Fixing

Pegged

Mid

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Colloquial Name	Description	OrdType	TimeInForce	Venue	Cancel on Disconnect?
Market	An instruction to deal immediately at the best possible price (the current rate).	Market	DAY	BME	YES
Limit	An instruction to deal if a market moves to a MORE favourable level.	Limit	DAY	BME	YES
Immediate Limit		Limit	IOC	BME, AGG	N/A
		Limit	GTC	AGG
Fill or Kill		Limit	FOK	BME	N/A
Stop-Loss	An instruction to deal if a market moves to a LESS favourable level.	Stop Loss
		Stop Loss	GTC	AGG
Stop Limit	Executes an exposure-reducing limit order when market exceeds order's price.	Stop Limit	DAY		YES
		Stop Limit	GTC	AGG
Stop-Trailing	The Stop Price follows the market by a specified offset.	Trailing Stop
Market Limit	Order that starts as a Market order and executes any leaves quantity as a Limit order.	Market With Leftover As Limit
Auction Price		Market	OPN*		YES
Previously Quoted	An order to hit an individual quote. To hit multiple quotes, aka sweeping, the user must submit individual orders from best to worst price.	Previously Quoted		BME
VwapSweep	An order that can hit/lift one or multiple quotes by submitting an order with the desired amount and the Volume Weighted Average Price (VWAP) of the total amount.	VWAP Sweep		CitiCoLo
TWAP		Limit	GFT/GTD
Attack				BME
Stop limit at rise	Determined by Side?			BME
Stop limit at fall	Determined by Side?			BME
Market Maker				BME
Limit Take Profit
Fixing
Pegged
Mid