NIC

• network interface card/network adapter

  • laptops generally have 2+ ([[Wi-Fi]], ethernet)
    • generally built in now, but used to be plug-in (needed to install corresponding drivers manually)
  • each NIC has
    • speed rating - 10 Mbps, 100 Mbps, 1000 Mbps, 1 Gbps
    • driver software - software to pass data btwn OS and NIC
    • MAC address

• a bunch of these on a router

  • each router port has a NIC, each port is thus associated w a MAC address

• note

  • the dest mac add of a packet changes
  • dest IP of packet never changes

• to show NIC on:

  • [[windows]] ipconfig /all
    • shows up as “Ethernet adapter local connection” for wired network or “ethernet adapter wireless network connection
  • Mac OS X ifconfig
    • shows up as “en0, en1...” for each NIC in your computer
  • Linux and Unix ifconfig
    • shows up as “en0, en1...” for each NIC in your computer