1. No category

L3 Forwarding
L3 packet walk through brief of S9700
Lookup HiGig HDR to
make forward
decision. No check
inner content. Also do
Fabric MC replication
Switch
Fabric
HiGig_Hdr
Original Frame
Switch
Fabric
HiGig_Hdr
Original Frame
HiGigs
HiGigs
HiGigs
Packet
Processor
Ingress
Module
HiGigs
PP
(LSW)
Ingress
Port
Take all table
lookup, find the dst
module(s) & port(s)
Packet
Lookup HiGig HDR to
make forward
decision. Just a few
Egress action.
PP PP
(LSW)
(LSW)
Egress
Port
Packet
Processor
Egress
Module
Packet
1
L3 packet walk through brief of S9700
L2/L3/ACL
Table
Parse
Lookup
ACL …
Ingress linecard
Egress linecard
Ingress PP
Egress PP
Memory
Management
Unit
Ingress
Module’s
Ingress pipeline
Fabric
Packet
Modification
HiGig
Ingress
Module’s Egress
pipeline
HiGig
Parse
Lookup
ACL …
Egress Module’s
Ingress pipeline
Memory
Management
Unit
ACL
Table
Packet
Modification
Egress Module’s
Egress pipeline
Ingress forwarding
1. The Ingress Module execute almost all tasks, like (MPLS/L2/L3)
forwarding lookup, ACL, get the dst_module & dst_port; Write these
information into HiGig_Header, send it out.
2. Fabric will forwarding the packet according the HiGig_header
3. The Egress Module abstract the inner frame from the HiGig packet, send
it to the dst-port according the HiGig_Header. [ No MPLS/L2/L3
forwarding lookup action, except Egress MC replication/Egress
ACL/Egress Rewrite... etc. ]
2
L3 Unicast Packet Processor’s pipeline Brief
Ingress Pipeline
Preprocess
ilLegal Check
Allocate/Fill
“internal header”
……
Tunnel
Termination
Ingress VLAN
assignment
MPLS
Lookup
Tunnel Decap.
Tunnel-decap
Assign VLAN-ID
Set CoS
VLAN Translate …
Ingress V/PACL
MPLS action.
Swap or pop
Egress Pipeline
Get Adj. info &
Tunnel Encap.
Traffic Management &
Multicast Replication
L3 &
Tunneling
Buffer/Queue/Shaping/Scheduler
…
IP Multicast Replication
Egress VLAN
assignment
Egress VLAN assign
STP Check, etc ……
Egress
ACL
ACL/Statistics/Policing(CAR) ……
Packet Rewrite
Modify the original packet
Get the final result ……
3
L2
Lookup
L3
Lookup
LPM & IPMC
L3 ECMP
Ingress
ACL
Ingress RACL
ACL/PBR/Policing(C
AR)/Stats/stream
SPAN …
Punt to CPU
L3 Lookup Detail Process
Next-Hop
Index
YES
Adj. Table
LPM
TCAM
NO
L3 ECMP
Host Table
Packet
YES
YES
Unlike catalyst or Nexus, we use a
dedicate CAM for host table. ARP
is limited by this table.
Cisco is placed this into L3 FIB,
so it’s FIB is not so large as
their declare. But it’s more
flexible.
4
Hash for ECMP
Next-Hop index
Selection
Packet
Rewrite
ECMP Detail
L3 ECMP
ECMP Resource
Hash for ECMP NextHop index Selection
ECMP Load-balance
ecmp load-balance { diffluence | sip [ dip ]
[ port ] }
ECMP Resource according to LC’s capability
<Quidway> system-view
[Quidway] ecmp load-balance sip
ECMP Load-balance enhanced
ecmp load-balance enhanced profile profile-name
undo ecmp load-balance enhanced profile profile-name
ipv4 field [ sip ] [ dip ] [ vlan ] [ l4-sport ] [ l4-dport ]
[ protocol ] [ sport | dport ]
<Quidway> system-view
[Quidway] ecmp-profile test
[Quidway-ecmp-profile-test] ipv4 field sip protocol
5
L3 Multicast Packet Processor’s pipeline
Brief
Ingress Pipeline
Preprocess
ilLegal Check
Allocate/Fill
“internal header”
……
Tunnel
Termination
Ingress VLAN
assignment
MPLS
Lookup
Tunnel Decap.
Tunnel-decap
Assign VLAN-ID
Set CoS
VLAN Translate …
Ingress V/PACL
MPLS action.
Swap or pop
Egress Pipeline
Get Adj. info &
Tunnel Encap.
Traffic Management &
Multicast Replication
L3 &
Tunneling
Buffer/Queue/Shaping/Scheduler
…
IP Multicast Replication
Egress VLAN
assignment
Egress VLAN assign
STP Check, etc ……
Egress
ACL
ACL/Statistics/Policing/CAR ……
Packet Rewrite
Modify the original packet
Get the final result ……
6
L2
Lookup
L3
Lookup
LPM & IPMC
L3 ECMP
Ingress
ACL
Ingress RACL
ACL/PBR/Policing/C
AR/Stats/stream
SPAN …
Punt to CPU
Unicast GRE packet flow
Tunnel
Preprocess
Termination
ilLegal Check
Allocate/Fill
“internal header”
……
Tunnel Decap.
Tunnel-decap
Ingress Pipeline
Ingress VLAN
MPLS
assignment
Lookup
Assign VLAN-ID
Set CoS
VLAN Translate …
Ingress V/PACL
MPLS action.
Swap or pop
L2
Lookup
L3
Lookup
LPM & IPMC
L3 ECMP
Egress Pipeline
Get Adj. info &
Tunnel Encap.
Traffic Management &
Multicast Replication
L3 &
Tunneling
Buffer/Queue/Shaping/Scheduler …
IP Multicast Replication
Egress VLAN
assignment
Egress VLAN assign
STP Check, etc ……
Egress
ACL
ACL/Statistics/Policing/CAR ……
Packet Rewrite
Modify the original packet
Get the final result ……
7
Ingress
ACL
Ingress RACL
ACL/PBR/Policing/C
AR/Stats/stream
SPAN …
Punt to CPU
Multicast GRE packet flow
（ For MPLS VPN Multicast）
For Carrier’s
Outer GRE
Multicast
replication &
forwarding
PE
Transit MVPN
Traffic
PE
Replication &
Forwarding
For Inner (VPN)
Multicast
replication &
forwarding
PE
CE
8
HUAWEI ENTERPRISE ICT SOLUTIONS A BETTER WAY
Copyright©2012 Huawei Technologies Co., Ltd. All Rights Reserved.
The information in this document may contain predictive statements including, without limitation, statements regarding the future financial and
operating results, future product portfolio, new technology, etc. There are a number of factors that could cause actual results and developments to
differ materially from those expressed or implied in the predictive statements. Therefore, such information is provided for reference purpose only and
constitutes neither an offer nor an acceptance. Huawei may change the information at any time without notice.