Let's say I'm routing orders to ARCA and I want to quickly (automatically) cancel/submit orders. I'm using Sterling and the clearing is done by PAX in Chicago. Does my order get matched in Chicago or is there a central ARCA server in NYC or NJ that orders are going to? If the latter, how fast is that connection between Chicago and NYC? This AT&T graphic says it's 22ms from CHI to NYC. http://ipnetwork.bgtmo.ip.att.net/pws/network_delay.html Speed of light is 186,000miles/s and CHI is 711.47 miles from NYC, which I guess means light can get there and back 130.7 times per second - so I guess that's the physical barrier: 7.65ms.
your clearer just settles your trades. this is usually done after the trading day in a large batch run pairing your buys and sells. clearing doesn't happen at time of execution and doesn't affect time to execution. latency to chicago from ny is a huge variable. not including the number of hops you go through, you're still going through someone else's servers: sterling's. even if you were able to get your order there by your theoretical minimum, it could take sterling a couple of hundred milliseconds to process your order and get it to the exchange. if you're interested in figuring out the exact order time to live measured in milliseconds, you have quite a bit of work ahead of you. it's not trivial. if you want a good guestimate, count on it starting at around 200ms.
depends if you're doing programs from your site to sterling or if you're co-locating at sterling or if you're at the NJ site at Arca co-locating doing sponsored access. Lots of variables.