1. Smart network engineers carefully design and manage networks to control traffic flow and network security through access lists. Access lists allow segmentation of network access and filtering of traffic but cannot replace firewalls.
2. Access lists begin working immediately after being applied to an interface and allow removal of individual lines. The no access-list command removes an access list. Wildcard masks determine which bits in an address are significant for access lists.
3. Extended access lists can filter traffic based on source and destination addresses, protocol, and port number while standard lists filter on source address only. Named access lists identify themselves through names instead of numbers.