How is data written to a blockchain? append only
rewrite always
append never
full read and write

Usually, when we sniff packets, we are only interested certain types of packets. we can do that by setting filters in sniffing. scapy’s filter use the bpf (berkeley packet filter) syntax; you can find the bpf manual from the internet. set the following filters and demonstrate your sniffer program again (each filter should be set separately): (a) capture only the icmp packet. (b) capture any tcp packet that comes from a particular ip and with a destination port number 23. (c) capture packets comes from or to go to a particular subnet. you can pick any subnet, such as 128.230.0.0/16; you should not pick the subnet that your vm is attached to.