MUST，SHOULD，DON 'T CARE：TCP在野生环境中的近亲繁殖
MUST, SHOULD, DON'T CARE: TCP Conformance in the Wild
摘要：
标准为协议实现者管理了互操作性的SHOULD和MUST要求。如果TCP承载了大量的互联网流量，这些要求在RFC中定义。虽然我们知道并非所有可选特性都被实现，并且存在不一致性，但我们可以假设TCP实现至少符合MUST要求的最小集合。在本文中，我们使用互联网范围内的扫描，以显示互联网主机和路径符合这些基本要求。我们发现了一组不可忽视的主机和路径，甚至不符合基本要求。例如，我们观察到主机不能正确处理校验和以及TCP选项的中间盒干扰情况。我们识别当紧急指针被设置或简单地崩溃时丢弃数据包的主机。我们公开的结果强调，即使是基本的协议要求的一致性不应该被视为理所当然，而是定期检查。
英文摘要：
Standards govern the SHOULD and MUST requirements for protocol implementers for interoperability. In case of TCP that carries the bulk of the Internets' traffic, these requirements are defined in RFCs. While it is known that not all optional features are implemented and nonconformance exists, one would assume that TCP implementations at least conform to the minimum set of MUST requirements. In this paper, we use Internet-wide scans to show how Internet hosts and paths conform to these basic requirements. We uncover a non-negligible set of hosts and paths that do not adhere to even basic requirements. For example, we observe hosts that do not correctly handle checksums and cases of middlebox interference for TCP options. We identify hosts that drop packets when the urgent pointer is set or simply crash. Our publicly available results highlight that conformance to even fundamental protocol requirements should not be taken for granted but instead checked regularly.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
