ARP flags

[Oqak]

Muze nekdo objasnit vyznam jednotlivych atributu - Flags, HW Type, Mask?

$ cat /proc/net/arp
IP address       HW type     Flags       HW address            Mask 
Device
192.168.10.10    0x1         0x2         00:1A:A2:F4:42:18     *        br0

A dale by me zajimalo, za jak dlouho po vypnuti PC zmizi standardne zaznam z 
ARP tabulky routeru?

Dik.