In the address ab00:fc87:234a:0090:5120:ffab:bc8a:0098/23, what does the /23 indicate?

The notation "/23" in the address ab00:fc87:234a:0090:5120:ffab:bc8a:0098/23 indicates the number of bits used for the network portion of the address. In an IPv6 address, which consists of 128 bits total, the "/23" specifies that the first 23 bits are designated for the network portion, while the remaining bits are allocated for the host portion.

By defining the network portion using this bit-length, it allows network routers and devices to effectively distinguish between addresses that belong to the same network and those that belong to different networks. The choice of how many bits to allocate for the network versus the host portion is crucial for proper routing and network management.

This understanding is essential for network administrators when designing subnet structures, managing IP allocations, and implementing security protocols within a network.