A replay attack (also known as playback attack) is a form of network attack in which a valid data transmission is maliciously or fraudulently repeated or delayed. This is carried out either by the originator or by an adversary who intercepts the data and re-transmits it, possibly as part of a masquerade attack by IP packet substitution.
Another way of describing such an attack is: “an attack on a security protocol using replay of messages from a different context into the intended (or original and expected) context, thereby fooling the honest participant(s) into thinking they have successfully completed the protocol run.”
Today's Poloniex press release:
As stated in the recently-published hard fork contingency plan, Poloniex agrees that any contentious hard fork must include replay attack protection. Without this, exchanges cannot continuously and properly operate.
Why can’t we pause markets until a "winner" emerges?
Unlike a planned fork where the block height is known, Bitcoin Unlimited can activate at an unknown date and time; therefore it is not possible to plan for such an event.
Are you going to support Bitcoin Unlimited or Bitcoin Core?
We will support Bitcoin Core continuously as BTC. In line with our current internal policy, if you have Bitcoin on balance at the time of the fork, we will make Bitcoin Unlimited available for withdrawal provided it is safe to do so. At a minimum, any new fork must include built-in replay protection. Without replay protection, we would be unable to preserve customers' Bitcoin Unlimited without halting Bitcoin withdrawals, which is unfeasible.
At this time, we have not determined whether or not we will be listing Bitcoin Unlimited.
So far the only case I'm hearing for SegWit is that the Bitcoin Core team is smarter than the Bitcoin Unlimited team and you know how that sounds like to me?
Childish.
I wrote this poem 3 days ago about how much I love Poloniex, it's inspired by true events.
