Cisco ASR 5000 Series, Обзор продукта

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Network Address Translation Overview
▀ How NAT Works
▄ Cisco ASR 5000 Series Product Overview
OL-22938-02
Figure 199. ... NAT Processing Flow
F lo w lim it p e r
s u b s c rib e r re a c h e d
no
yes
U p d a t e s t a t is t i c s
a n d d r o p t h e
p a c k e t
Is p a c k e t f ra g m e n te d
no
yes
B u f f e r a n d w a i t f o r
f r a g m e n ts
I P h e a d e r c h e c k s
U p d a t e s t a ti s t ic s
a n d D o S a t t a c k s ,
a n d d ro p t h e
p a c k e t
fail
pass
M a tc h in g fl o w e x i s t s
f o r t h e p a c k e t
U p d a te f lo w s t a t s
f o r p a c k e t
yes
no
T r a n s p o rt la y e r
h e a d e r a n d s t a t e
c h e c k s
fail
pass
U p d a te s t a ti s t ic s
a n d D o S a t t a c k s ,
a n d d ro p t h e
p a c k e t
I P R e a s s e m b ly
U p d a t e s ta t is t ic s
a n d d ro p th e
p a c k e t
fail
done
In prog ress
T r a n s p o r t l a y e r
h e a d e r a n d s ta t e
c h e c k s
U p d a t e s t a t is t ic s
a n d d ro p t h e
p a c k e t
fail
pass