How ARP Cache Work in linux?
I Know the ARP protocol uses and the role of the cache but I have difficulty
understanding the difference between various states of the entries in the ARP Cache like : permanent , noarp , reachable , stale .
I have found the following text explaining them :
The permanent state indicates a valid entry that can only be deleted
manually, the noarp state designates a valid entry that expires at the
end of its lifetime, the reachable state shows a valid entry that
expires when its reachability timeout expires, and the stale state
specifies a valid but suspicious entry.
but I have some difficulty understanding the difference between the meaning of terms like "lifetime" vs "reachability timeout" , "valid" vs suspicious .
I feel the existence of counters/timers in the mechanism and a state diagram but can't figure out the essential documentation source that
explain the mechanism after googling that, so it will be appreciated
mentioning the source documentation I was supposed to search into or
read from .
Thanks
linux linux-kernel arp
add a comment |
I Know the ARP protocol uses and the role of the cache but I have difficulty
understanding the difference between various states of the entries in the ARP Cache like : permanent , noarp , reachable , stale .
I have found the following text explaining them :
The permanent state indicates a valid entry that can only be deleted
manually, the noarp state designates a valid entry that expires at the
end of its lifetime, the reachable state shows a valid entry that
expires when its reachability timeout expires, and the stale state
specifies a valid but suspicious entry.
but I have some difficulty understanding the difference between the meaning of terms like "lifetime" vs "reachability timeout" , "valid" vs suspicious .
I feel the existence of counters/timers in the mechanism and a state diagram but can't figure out the essential documentation source that
explain the mechanism after googling that, so it will be appreciated
mentioning the source documentation I was supposed to search into or
read from .
Thanks
linux linux-kernel arp
add a comment |
I Know the ARP protocol uses and the role of the cache but I have difficulty
understanding the difference between various states of the entries in the ARP Cache like : permanent , noarp , reachable , stale .
I have found the following text explaining them :
The permanent state indicates a valid entry that can only be deleted
manually, the noarp state designates a valid entry that expires at the
end of its lifetime, the reachable state shows a valid entry that
expires when its reachability timeout expires, and the stale state
specifies a valid but suspicious entry.
but I have some difficulty understanding the difference between the meaning of terms like "lifetime" vs "reachability timeout" , "valid" vs suspicious .
I feel the existence of counters/timers in the mechanism and a state diagram but can't figure out the essential documentation source that
explain the mechanism after googling that, so it will be appreciated
mentioning the source documentation I was supposed to search into or
read from .
Thanks
linux linux-kernel arp
I Know the ARP protocol uses and the role of the cache but I have difficulty
understanding the difference between various states of the entries in the ARP Cache like : permanent , noarp , reachable , stale .
I have found the following text explaining them :
The permanent state indicates a valid entry that can only be deleted
manually, the noarp state designates a valid entry that expires at the
end of its lifetime, the reachable state shows a valid entry that
expires when its reachability timeout expires, and the stale state
specifies a valid but suspicious entry.
but I have some difficulty understanding the difference between the meaning of terms like "lifetime" vs "reachability timeout" , "valid" vs suspicious .
I feel the existence of counters/timers in the mechanism and a state diagram but can't figure out the essential documentation source that
explain the mechanism after googling that, so it will be appreciated
mentioning the source documentation I was supposed to search into or
read from .
Thanks
linux linux-kernel arp
linux linux-kernel arp
asked 2 mins ago
AbdAllah TalaatAbdAllah Talaat
535
535
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