# Market Data Subscription

HawkAlpha utilizes a users Alpaca’s market data subscription via a web-socket connection. 

{% hint style="info" %}
The users market data is only used by the user, only when the user has their VPS is running, and is not shared with HawkAlpha or other users in any way. [Read more on this here](https://hawkalpha.gitbook.io/what-is-hawkalpha/alpaca-broker/regarding-market-data-licensing).
{% endhint %}

A SIP market data subscription is automatically preferred for faster order placement. If a SIP market data plan isn't detected then HawkAlpha will rely on IEX. 

Alpaca offers market data access for its users via its Market Data API. Alpaca’s market data includes 100% market coverage for real-time and historical data for US stocks and ETFs. There are two options of obtaining data from Alpaca: SIP or IEX.

* SIP market data includes all securities exchanges’ and alternative trading venues’ price and volume data, which provides a consolidated view of the U.S. stock market. SIP market data also underpins the National Best Bid and Offer (NBBO), which shows the best available displayed buy and sell prices for each stock.
* IEX market data only includes orders and executions on the IEX exchange, which account for about 2% of the total market. 

[Alpaca sells access for their SIP market data](https://alpaca.markets/data). Users may chose to subscribe to receive faster quote data, as well as better market data coverage for extended market hours. 

{% hint style="info" %}
HawkAlpha recommends a SIP market data subscription if users are running bots on highly volatile stocks or the users strategy *resembles* a high-frequency trading pattern.

**Alpaca Markets is not a high frequency trading platform**. While an automated trading strategy can send trades to the market at a high frequency, Alpaca does not support the necessary speed of either market data flow or trade execution speed necessary for a high frequency trading program to function as intended.
{% endhint %}


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