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IP Hash Algorithm - Load Balancing | Network Design | Repovive

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Network Design26 sections · 911 units44h total

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IP Hash Algorithm

Consistent client routing

IP hash uses the client's IP address to determine which server receives their request. The same IP always goes to the same server.

function ipHash(clientIp, servers):
    hash = hashFunction(clientIp)
    index = hash mod servers.length
    return servers[index]

Time complexity is $O(1)$ . Space is $O(n)$ for the server list.

IP hash provides a form of session persistence without cookies. All requests from $192.168.1.100$ reach the same backend. But if servers are added or removed, the mapping changes and clients may shift to different servers.