Solution:

A data collision may take place when hashing data or when calculating a checksum.

A hash function reduces data to a smaller value and is often used in compression and cryptography.

While the hash operation may save disk space, two different inputs may produce the same output. Multiple hash functions can be used to avoid duplicate values when a collision occurs.

Bitmap protocol:

In this method, there are N slots. If node 0 has a frame to send, it transmits a 1-bit during the first slot. No other node is allowed to transmit during this period.

Next node 1 gets a chance to transmit 1 bit if it has something to send, regardless of what node 0 had transmitted.

In this collision-free protocol, the basic bit-map method, each contention period consists of exactly N slots. If station 0 has a frame to send, it transmits a 1-bit during the zeroth slot.

No other station is allowed to transmit during this slot. Regardless of what station 0 does, station 1 gets the opportunity to transmit a 1 during slot 1, but only if it has a frame queued. In general, station j may announce that it has a frame to send by inserting a 1 bit into slot j.

After all N slots have passed by, each station has complete knowledge of which stations wish to transmit. At that point, they begin transmitting in numerical order.

Since everyone agrees on who goes next, there will never be any collisions.

After the last ready station has transmitted its frame, an event all stations can easily monitor, another N-bit contention period is begun.

If a station becomes ready just after its bit slot has passed by, it is out of luck and must remain silent until every station has had a chance and the bit map has come around again.

Protocols like this in which the desire to transmit is broadcast before the actual transmission are called reservation protocols.