2.3 Signal Flow on the Data Plane
The data plane processes and forwards data packets at a high speed. The signal flow in the data
plane is primarily service data signals.
Signals on the data plane flow through a physical link, an uplink board, an SFU, a downlink
board, and another physical link.
illustrates the processing and forwarding of a signal flow on the data plane.
Figure 2-3
Processing and forwarding of a signal flow on the data plane
SFU
SFU cell
MPU
Packets
Host packets
Ph
ys
ica
l lin
k
Uplink
PIC
Uplink TM
Tra
ffic
sh
ap
in
g
C
on
ge
stio
n
m
an
ag
em
en
t
Uplink FIC
Fra
gm
en
ta
tio
n
Frames
Packets
Packets
O
ptic
al
or
ele
ctr
ica
l
sig
na
ls
Uplink board
Ph
ys
ica
l lin
k
Downlink
PIC
Downlink NP
Downlink TM
Tra
ffic
sh
ap
ing
C
on
ge
stio
n
m
an
ag
em
en
t
Downlink FIC
Pa
ck
et
pro
ce
ss
in
g
SFU cell
Packets
Packets
Frames
M
ult
ica
st
re
plic
atio
n
O
utb
ou
nd
in
te
rfa
ce
pro
ce
ss
ing
D
ata
lin
k la
ye
r
in
fo
rm
atio
n
Tra
ffic
cla
ss
ific
atio
n
O
ptic
al
or
ele
ctr
ica
l s
ig
na
ls
Downlink board
Uplink NP
R
ou
te
-b
as
ed
fo
rw
ard
in
g
In
bo
un
d in
te
rfa
ce
pro
ce
ss
ing
Tra
ffic
cla
ss
ific
atio
n
(local attack defense)
Acronyms
PIC: physical interface controller
NP: network processor
TM: traffic manager
FIC: fabric interface controller
C
A
R
tra
ffic
p
olic
in
g
C
on
ge
stio
n
av
oid
an
ce
C
on
ge
stio
n
av
oid
an
ce
C
A
R
tra
ffic
po
lic
in
g
The processing of an incoming signal flow is as follows:
1.
An uplink physical interface card (PIC) provides an inbound interface for a signal flow.
Optical and electrical signals transmitted along a physical link enter the uplink PIC. The
PIC obtains the physical layer clock frequency and performs data layer link protocol
negotiation. Then the PIC encapsulates packets into Ethernet frames and sends the frames
to the uplink NP.
HUAWEI CX600-8/16/X3/X8/X16 Metro Service Platform
Hardware Description
2 Product Signal Flow Overview
Issue 03 (2013-11-30)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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