← Microsoft Interview Insights
Rattled off the obvious ones: 22 for SSH, 80 and 443 for HTTP/HTTPS, 3389 for RDP, 445 for SMB.
Start by clarifying that 'common ports' can refer to well-known ports (0-1023) used by standard services, and that both Windows and Unix workstations typically use the same IANA-assigned ports for cross-platform services. Then group ports by function (e.g., web, email, file transfer, remote access, directory services) and mention a few examples per group, noting any platform-specific nuances.
Pro tip: Emphasize that while the port numbers are standardized, the services listening on them may differ by platform (e.g., Windows uses SMB on 445, while Unix uses NFS on 2049). Also, mention that modern workstations often use ephemeral ports for outbound connections, so the 'common' ports are primarily for inbound services.
State that you'll focus on well-known ports (0-1023) assigned by IANA, which are used by both Windows and Unix workstations for common services. Mention that ports 1024-49151 are registered but less commonly used on workstations.
Organize your answer into categories such as web, email, file transfer, remote access, and directory services. This shows structured thinking and makes the answer easier to follow.
For each category, provide 1-2 well-known ports and the associated protocols (e.g., HTTP on 80, HTTPS on 443, SMTP on 25, SSH on 22, RDP on 3389).
Point out ports that are more common on one platform than the other, such as SMB (445) on Windows or NFS (2049) on Unix, and explain why (e.g., native file sharing protocols).
Note that some ports are often blocked or changed for security (e.g., RDP moved from 3389), and that many services now use TLS on standard ports (e.g., HTTPS on 443) or alternative ports (e.g., SSH on 2222).
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.