[c-nsp] BGP KEEPALIVE maximum frequency

[M. V.]

hi,

i have sort of a technical question.
RFC4271 (main RFC of BGP4) says: "KEEPALIVE messages MUST NOT be sent more 
frequently than one per second". i checked cisco with wireshark and saw it sends 
more than 1 KEEPALIVE (sometimes 2, but usually 3) in less than 1 second right 
after OPEN messages are sent. and then after that, everything gets back to 
normal, and it sends KEEPALIVEs just every 60 seconds. 

so i was wondering, why this thing happens. is it just an unimportant bug or it 
has a reason. 'cause i checked RFC and i didn't find anything regarding that. i 
got from RFC that router should send first KEEPALIVE when goes 
"OpenSent->OpenConfirm". then when goes to "Established" state, should start its 
KeepAlive-Timer and the next (2nd so far) KEEPALIVE message has to be sent 
after, say, 60 seconds )

thank you.