TCP/IP

TCP/IP protocol stack implementations across operating systems contain inconsistencies with RFC standards, including issues with ISN generation, TCP challenge acknowledgments, TCP authentication, and timestamp options. These inconsistencies can introduce serious security vulnerabilities such as traffic amplification, replay attacks, and TCP RST spoofing.

TCP/IP protocol design is fundamentally non-deterministic, aiming for overall network reliability rather than individual segment reliability. This architecture makes it unsuitable for financial transaction systems that require deterministic behavior and clear evidence of failures.

TCP/IP may not adequately scale to future Internet requirements including voice traffic, video streaming, and other emerging use cases. The protocol requires significant modification to handle future demands beyond its original design scope.

TCP/IP connectivity failures often stem from network interface card (NIC) malfunctions, incorrect IP address setup, DHCP server issues, or driver problems. Troubleshooting requires systematic verification of hardware, configuration, and connectivity.

TCP/IP protocol does not differentiate between traffic priorities (e.g., interactive web traffic vs. email). This lack of prioritization is a major cause of perceived Internet slowness and is one of several fundamental architectural limitations of the current protocol suite.

Incorrect VLAN configurations or switch port settings can block communication between network devices. Hardware malfunctions such as faulty network interfaces or cables further exacerbate communication problems.

Network configurations gradually diverge from documented network diagrams over months and years. Configuration drift makes troubleshooting exponentially more difficult as actual configurations no longer match design documentation.