Using my phone as hotspot for my Ipad on which I trade ,latency ?

Your order will be verified by your broker first and then the broker will sent it to the exchange.

 

What if I'm in the same DC as my broker? Not that I trade any HFT algos... but just hypothetically.

 

It doesn't matter. It's a regulatory issue, not a tech one.

 

Lol, understood. What if my counterparty has the same regulatory hurdles but has a ping closer to 1500ms?