ATH max packet size?
sam at errno.com
Fri Feb 17 09:56:59 PST 2006
Sten Daniel Sørsdal wrote:
> I am still waiting for my PCI -> MiniPCI bridge for my CM9 card so i am
> unable to test this, and even though i read the source i am still
> unsure, so i was hoping a kind generous soul would answer my question;
> What is the max packet size (mtu) available using the ath driver?
> The reason i ask is, i want to setup a tunnel between two units and
> optimally not have to deal with any fragmentation issues.
* Maximum acceptable MTU is:
* IEEE80211_MAX_LEN - WEP overhead - CRC -
* QoS overhead - RSN/WPA overhead
* Min is arbitrarily chosen > IEEE80211_MIN_LEN. The default
* mtu is Ethernet-compatible; it's set by ether_ifattach.
#define IEEE80211_MTU_MAX 2290
#define IEEE80211_MTU_MIN 32
ath can actually handle very large packets (64K I believe) but the
current driver won't chain rx descriptors together so it's limited to an
mbuf cluster (2K).
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