Nortel 1200N, Руководство пользователя

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Line Interface Hardware Interface
6-10 Centillion 1200N ATM Switch User Manual
NTP 297-8103-903
Figure 6-11: ATM Cell Format
U N I: U se r-N e tw o rk In te rfa ce
N N I: N e tw o rk-N e tw o rk In te rfa ce
G F C : G e n e ric F lo w C o n tro l
V P I: V irtu a l P a th Id e n tifie r
V C I: V irtu a l C h a n n e l Id e n tifie r
P T: P a y lo a d Typ e
C L P : C e ll L o ss P rio rity
H E C : H e a d e r E rro r C o n tro l
U N I
M S B L S B
G F C (4 )
V P I(4 )
V P I(4 )
V C I(4 )
V C I(4 )
V C I(8 )
P T (3 )
H E C (8 )
U se r In fo rm a tio n
(1 )
C L P
N N I
V P I(4 ) V C I(4 )
V P I(8 )
M S B L S B
V C I(4 )
V C I(8 )
P T (3 )
H E C (8 )
U se r In fo rm a tio n
(1 )
C L P
pa
y
loa
d 48B
y
te
h
e
a
der
5B
y
te
ce
ll 5
3
B
yt
e
G F C V P I V C I
0 0
1
2
3
4
5
1 6
x
x
x
x
x
x
u s e
u n a s s ig n e d c e ll
m e ta s ig n a llin g (d e fa u lt V P I= 0 )
g e n e ra l b ro a d c a s t s ig n a llin g (d e fa u lt V P I= 0 )
s e g m e n t O A M F 4
e n d -to -e n d O A M F 4
e n d -to -e n d O A M F 5
re s e rve d fo r tra ffic c o n t. a n d re s o u rc e m a n .
p o in t-to -p o in t s ig n a llin g (d e fa u lt V P I= 0 )
IL M I (In te rim L o c a l M a n a g e m e n t In te rfa c e )
s e g m e n t O A M F 5
u s e r d a ta c e ll, n o c o n g e s tio n , S D U -typ e = 0
u s e r d a ta c e ll, c o n g e s tio n , S D U -typ e = 1
u s e r d a ta c e ll, c o n g e s tio n , S D U -typ e = 0
u s e r d a ta c e ll, n o c o n g e s tio n , S D U -typ e = 1
re se rve d
P T
0
0
0
0
0
0
0
0
0
0
x
a n y
v a lu e
o th e r
th a n
0
x
0 ,2
0 ,2
0 ,2
7
0 -3
0 -3
C L P
1
n o rm a l p rio rity
lo w e r p rio rity
0
1
2
3
4
5
6
*
*
*
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