通过协议可以延长期限。

Period may be extended upon expiration (through agreement).

《新英汉大辞典》

可通过协议或通过实现一系列规则强制执行信任策略来手动链接。

It can be articulated manually, by an agreement, or by implementing a set of rules enforcing the trust policy.

youdao

客户端和服务器的程序必须通过协议规定的过程和数据类型进行通信。

The client and server programs must communicate via the procedures and data types specified in the protocol.

youdao

So it's going to be pretty difficult for us to sustain this joint monopoly output, this collusive agreement.

因此说想要通过私下协议来,维持垄断产量,是非常困难的

耶鲁公开课 - 博弈论课程节选

Well, one thing that goes wrong is that suppose Coke and Pepsi were able to either to write a contract or whatever to sustain joint monopoly output at this high price, this price which is actually producing positive profits in the industry it is going to turn out, therefore the price is going to be above costs.

我来说吧,问题出在这里了,假设可口可乐和百事达成了协议,不管签的是协议还是合同,只要能通过协约维持垄断产出,通过制定高价来达到正的利润就行,这样价格是高于成本的

耶鲁公开课 - 博弈论课程节选