A firewall rule allows for connections on 1.2.3.4/8. What does the /8 mean and which other IP addresses (range) will be recognized as allowed. Describe which IP ranges would be allowed if the rule specified 1.2.3.4/16 or 1.2.3.4/24. What about 1.2.3.4/32 ?

this is called CIDR — classless internet domain routing

/8 — means just the first octet must match, in our example, the range would be 1.0.0.1 to 1.255.255.254

/16 — first & second octet must match, in our example, the range would be 1.2.0.1 to 1.2.255.254

/24 — first, second & third octet must match, in our example, the range would be 1.2.3.1 to 1.2.3.254

/32 — all four octets must match — which is the same thing as leaving the IP address without any CIRD; in our example, the range would be 1.2.3.4 to 1.2.3.4