MacOS – the network interface ‘llw0’

macosNetwork

An interface called llw0 shows up in ifconfig and has the same IPv6 address (different scopeid) and hardware address as awdl0:

awdl0: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> mtu 1484
   options=400<CHANNEL_IO>
   ether 42:f8:7a:c4:5a:b6
   inet6 fe80::e8de:dfa2:fe4f:f1e%awdl0 prefixlen 64 scopeid 0xd
   nd6 options=201<PERFORMNUD,DAD>
   media: autoselect
   status: active
llw0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
   options=400<CHANNEL_IO>
   ether 42:f8:7a:c4:5a:b6
   inet6 fe80::e8de:dfa2:fe4f:f1e%llw0 prefixlen 64 scopeid 0xe
   nd6 options=201<PERFORMNUD,DAD>
   media: autoselect
   status: active

awdl0 is Apple Wireless Direct Link, but what is llw0?

Best Answer

llw is a WLAN low-latency interface, and llw0 is simply the first of those.

The llw interface is a network interface that comes from a nexus defined in the Skywalk system. You can look it up like this:

skywalkctl list-providers | grep llw

You'll see that it is handled by a BCM "driver" (i.e. an IC in your computer manufactured by Broadcom).

The interface is supposed to be there - it is not a bug.

Similar to how awdl (that you mention) is a special kind of WiFi connection that is peer-to-peer and low-latency (used for AirDrop for example) - llw is also a special kind of WiFi connection that is low-latency (no power saves allowed), but with an access point.

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