The certificate exchange occurs at least once (and potentially twice) while the SSL connection request is negotiated.

当协商SSL连接请求时，至少发生一次(也有可能是两次)证书交换。

youdao

Uniquely in the public sector, royal civil list finances are negotiated – and debated by MPs –only once every 10 years.

皇室费用每过十年才会经历一次协商——以及国会议员关于此事的辩论，这在公共部门绝无仅有。

youdao

Not for the first time, disagreement arose at once about what had actually been negotiated.

这已经不是第一次了，一旦涉及到实际问题，就会出现分歧。

youdao

Once a contract has been negotiated and approved, a paper copy is typically signed and archived either in filing cabinets or in off-site storage.

FORBES: Legal Contract Management And The Modern Enterprise

And that coupling of realism and idealism, which has always represented what is best in American foreign policy, that was at the heart of his work in Bosnia, where he negotiated and cajoled and threatened all at once, until peace was the only outcome possible.

WHITEHOUSE: Remembering Richard Holbrooke

There will be a collective sigh of relief once this anniversary week has been (hopefully) safely negotiated.

ECONOMIST: New York city one year on