GENERAL
Introduce a bit more
Soften claims

AUTHOR LIST
* Antia under SPECTRAL now

ABSTRACT
* ..., based on bidirectional distribution, is claimed to be secure under assumption...
* "extent" narrow down to symmetric protocol

INTRODUCTION
* Small introduction to protocol's claims and assumptions, not so much tied to an attack.
* Channel works under the assumption of channel reciprocity.
* Proposed mechanism to detect asymmetry does not work.
* Mention previous experimental work and its advantages, motivate why we are looking into assymetrical delay attack
* Optically symmetrical channel where the only distinguishing property is the direction of propagation, not many mechanisms can sepearete them.
* TWTT satellite protocol chinese paper.
* Consequently, asymmetric network delays... may expose the scheme to attacks... 
* "accuracy"

SECTION 2: ATTACK ON...
* Entanglement was conjectured to detect the presencce of circulators, apart from use to perform authentication.
* Say directly what Eqn. 6 is saying.

SECTION 3: EXPERIMENT


CONCLUSION
* Compared to classical protocols...
* End on positive note
* while entangled photons secure authenticity, but does not prevent this attack
* e.g. of case when GP can be detected (Kwait..), requires interference...
* Sym necessary for protocol... come up with a physical situation that its not the case, cannot test the presence of an asymmetric delay by testing entanglement in the degree of freedom not associated with direction of propagation.