𝗨𝗻𝗱𝗲𝗿𝘀𝘁𝗮𝗻𝗱𝗶𝗻𝗴 𝗥𝗮𝘁𝗲 𝗟𝗶𝗺𝗶𝘁𝗶𝗻𝗴 𝗶𝗻 𝗔𝗦𝗣.𝗡𝗘𝗧 𝗖𝗼𝗿𝗲: 𝗪𝗵𝘆 𝗜𝘁 𝗠𝗮𝘁𝘁𝗲𝗿𝘀 𝗮𝗻𝗱 𝗛𝗼𝘄 𝘁𝗼 𝗜𝗺𝗽𝗹𝗲𝗺𝗲𝗻𝘁 𝗜𝘁 𝗳𝗼𝗿 𝗙𝗿𝗲𝗲 𝘃𝘀 𝗣𝗿𝗲𝗺𝗶𝘂𝗺 𝗨𝘀𝗲𝗿𝘀

Rate limiting is a crucial technique in ASP.NET Core to control how many requests a client can make within a specific time window. It helps protect your application from abuse, ensures fair usage, and maintains system stability.

𝗔𝗱𝘃𝗮𝗻𝘁𝗮𝗴𝗲𝘀 𝗼𝗳 𝗥𝗮𝘁𝗲 𝗟𝗶𝗺𝗶𝘁𝗶𝗻𝗴:

• Prevents API abuse and denial-of-service attacks
• Protects backend resources from overload
• Ensures fair access for all users
• Improves application reliability and security

𝗛𝗼𝘄 𝘁𝗼 𝗖𝗼𝗻𝗳𝗶𝗿𝗺 𝗜𝗳 𝗬𝗼𝘂𝗿 𝗔𝗽𝗽 𝗡𝗲𝗲𝗱𝘀 𝗥𝗮𝘁𝗲 𝗟𝗶𝗺𝗶𝘁𝗶𝗻𝗴:

• Detect spikes or repeated requests from the same user or IP
• Notice backend performance degradation under load
• Handle critical or expensive operations that require throttling
• Differentiate user plans with varied usage limits

𝗪𝗵𝘆 𝗨𝘀𝗲 𝗥𝗮𝘁𝗲 𝗟𝗶𝗺𝗶𝘁𝗶𝗻𝗴 𝗶𝗳 𝗜𝘁 𝗠𝗶𝗴𝗵𝘁 𝗨𝗽𝘀𝗲𝘁 𝗨𝘀𝗲𝗿𝘀?
Rate limiting protects the overall user base by preventing misuse or excessive requests that could degrade service for everyone. When implemented with reasonable limits, most users will never notice its impact.

𝗛𝗼𝘄 𝘁𝗼 𝗨𝘀𝗲 𝗥𝗮𝘁𝗲 𝗟𝗶𝗺𝗶𝘁𝗶𝗻𝗴 𝗪𝗶𝘁𝗵𝗼𝘂𝘁 𝗖𝗮𝘂𝘀𝗶𝗻𝗴 𝗗𝗶𝘀𝗰𝗼𝗺𝗳𝗼𝗿𝘁:

• Set generous, reasonable limits based on user behavior
• Customize error messages to guide users politely
• Use different limits for different endpoints or user tiers
• Implement retry-after headers and backoff strategies

𝗦𝗮𝗺𝗽𝗹𝗲 𝗖𝗼𝗱𝗲 𝗦𝗻𝗶𝗽𝗽𝗲𝘁: 𝗥𝗮𝘁𝗲 𝗟𝗶𝗺𝗶𝘁𝗶𝗻𝗴 𝗳𝗼𝗿 𝗙𝗿𝗲𝗲 𝘃𝘀 𝗣𝗿𝗲𝗺𝗶𝘂𝗺 𝗨𝘀𝗲𝗿𝘀 𝗶𝗻 𝗔𝗦𝗣.𝗡𝗘𝗧 𝗖𝗼𝗿𝗲

// Define rate limit policies based on user tier
options.AddPolicy("FreePolicy", context =>
RateLimitPartition.GetFixedWindowLimiter(context.Connection.RemoteIpAddress.ToString(), _ =>
new FixedWindowRateLimiterOptions { PermitLimit = 5, Window = TimeSpan.FromSeconds(10) }));

options.AddPolicy("PremiumPolicy", context =>
RateLimitPartition.GetFixedWindowLimiter(context.Connection.RemoteIpAddress.ToString(), _ =>
new FixedWindowRateLimiterOptions { PermitLimit = 20, Window = TimeSpan.FromSeconds(10) }));

𝗛𝗼𝘄 𝗵𝗮𝘃𝗲 𝘆𝗼𝘂 𝗯𝗮𝗹𝗮𝗻𝗰𝗲𝗱 𝗽𝗿𝗼𝘁𝗲𝗰𝘁𝗶𝗻𝗴 𝘆𝗼𝘂𝗿 𝗔𝗣𝗜𝘀 𝘄𝗶𝘁𝗵 𝗺𝗮𝗶𝗻𝘁𝗮𝗶𝗻𝗶𝗻𝗴 𝗮 𝘀𝗺𝗼𝗼𝘁𝗵 𝘂𝘀𝗲𝗿 𝗲𝘅𝗽𝗲𝗿𝗶𝗲𝗻𝗰𝗲 𝗶𝗻 𝘆𝗼𝘂𝗿 𝗮𝗽𝗽𝗹𝗶𝗰𝗮𝘁𝗶𝗼𝗻𝘀?