Networking
Concepts
Future
- Interplanetary Internet - What will the Internet look like when humanity has reached interplanetary status?
IPv6
The Office of Management and Budget (OMB) has instructed all Federal agencies to begin moving to Internet Protocol Version 6 (IPv6) starting in 2022. Completing the transition to an IPv6 infrastructure will require 20% of systems to move to IPv6 by the end of the Fiscal Year (FY) 2023 and 80% by FY 2025.
Subnetting Tools
I do a fair amount with IP ranges, especially on IPv6 and especially with Verizon which tends to change the IPv6 prefix they assign me every time a strong wind blows.
Often I find myself normalizing IPv4 addresses to a /24 network and IPv6 to a /56 CIDR and discovered that the Python 3 ipaddress
package does an excellent job of it.
I use the IPv6Interface
class to take in a IP address with a CIDR and then convert it to the network with ipaddress.IPv6Interface(f"{ip}/56").network
. The script below is a method I use to take a whole list of troublesome hosted server IPs from my log files and add them to my firewall as assigned ranges.
import ipaddress
import sys
def convert_to_cidr(ip_list):
converted_set = set()
for ip in ip_list:
if ':' not in ip:
# IPv4 handling, convert to /24 CIDR
network = ipaddress.IPv4Interface(f"{ip}/24").network
else:
# IPv6 handling, convert to /56 CIDR using IPv6Interface
network = ipaddress.IPv6Interface(f"{ip}/56").network
converted_set.add(str(network))
return converted_set
def main():
ip_list = [line.strip() for line in sys.stdin if line.strip()]
unique_cidrs = convert_to_cidr(ip_list)
print('\n'.join(sorted(unique_cidrs)))
if __name__ == "__main__":
main()