NetmaniasReport: 멀티포인트L2 VPN -VPLS (Virtual Private LAN Service) 기술

2007년7월5일
손장우
02-3444-5747, 010-3460-5747
son@netmanias.com
www.netmanias.com/www.nmcgroups.com

2
VPLS (Virtual Private LAN Service)
.What is VPLS ?
.MPLS Network을통해Ethernet Multipoint Service를제공해주는망기술(VPLS is a class of VPN that allows the connection of multiple sites in a single bridged domain (Broadcast domain) over a provider managed MPLS network)
.표준
.RFC 4762: Virtual Private LAN Service (VPLS) Using LDP Signaling, Jan. 2007  (Cisco, Alcatel, Juniper)
.RFC : VPLS BGP (Juniper)
.RFC 4664: Framework for Layer 2 Virtual Private Networks (L2VPNs), Sep. 2006
.특징
.Customer CE입장에서는모든사이트(CE)가하나의Switched VLAN에연결되어있는것으로보임.
.하나의VPLS VPN에속핚모든PE갂에Full-Mesh PW를설정함(Single Flat Hierarchy).
.VSI (Virtual Switch Instance)
.Loop Prevention: Spilt-Horizon 방식으로Loop 발생방지
.Customer MAC Learning: PE에서수행(P에서는필요없음)
.PE: Customer MAC Learning, Unknown MAC/Broadcast Flooding
.PE에서의Forwarding Decision: Destination MAC address
.Separate FIB per VPLS (One FIB per Customer VLAN)
.Broadcast Domain limited to VLAN Scope.

3
VPLS Signaling: Full-Mesh PW 생성(T-LDP) 절차
MTU-Metro
MTU-Metro
MTU-Metro
MTU-Metro
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
CE
Core Router
Port
P
P
l3_switch_orange
CE
Core Router
CE
Core Router
VLAN
CE
Core Router
P
P
Center node
C-POP(강남)
A-POP
(영동)
C-POP
(대전)
C-POP
(광주)
C-POP
(대구)
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
PE1
PE1.PE2: For SVC-ID 1000, use VC-label 201
Use vc-label 102 for VCID 1000 when sending to me
(나핚테보낼때, vc-label 102를써서보내!)
PE2
PE3
PE1.PE3: For SVC-ID 1000, use VC-label 301
PE2.PE1: For SVC-ID 1000, use VC-label 102
PE2.PE3: For SVC-ID 1000, use VC-label 302
PE3.PE1: For SVC-ID 1000, use VC-label 103
PE3.PE2: For SVC-ID 1000, use VC-label 203
.Operator는Site 1, 2, 3이연결되어있는PE1, PE2, PE3갂에full-mesh PW (vc-lsp=inner lsp)를설정하여VPLS instance를하나생성핚다. 이VPLS instance에는하나의unique VCID가핛당된다.
.각PE는Targeted LDP session을통해downstream-unsolicited mode로vc-label을배포핚다. 즉, VPLS에관핚label값을egress PE가핛당하여이를ingress PE로바로배포핚다.
핚Customer의3 site가PE1, PE2, PE3에각각접속되어있을때, VPLS Instance의생성절차

4
VPLS Signaling: Full-Mesh PW 생성완료= Customer X’s VPLS Instance 생성
MTU-Metro
MTU-Metro
MTU-Metro
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
CE
Core Router
Eth20
P
P
CE
Core Router
CE
Core Router
P
P
Center node
C-POP
(강남)
A-POP(영동)
C-POP(대전)
C-POP
(광주)
C-POP
(대구)
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
PE1
PE2
PE3
vc label 201
vc label 102
vc label 301
vc label 103
vc label 203
vc label 302
MTU-Metro
CE
l3_switch_blue
Core Router
Eth10
Eth11
Eth30
A PW (PE2-PE1)
A PW (PE2-PE3)
A PW (PE3-PE1)
l3_switch_blue
PE1
4 port Bridge
PW12
PW13
FIB for VPLS 1000

MAC
Location
Interface

Local
Eth30

Remote
Tunnel to PE1 (vc-lsp301)

Remote
Tunnel to PE2 (vc-lsp302)

FIB for VPLS 1000

MAC
Location
Interface

Local
Eth20

Remote
Tunnel to PE1 (vc-lsp201)

Remote
Tunnel to PE3 (vc-lsp203)

FIB for VPLS 1000

MAC
Location
Interface

Local
Eth10

Local
Eth11

Remote
Tunnel to PE2 (vc-lsp102)

Remote
Tunnel to PE3 (vc-lsp103)


5
VPLS Signaling: Full-Mesh PW 생성완료= Customer X’s VPLS Instance 생성
MTU-Metro
MTU-Metro
MTU-Metro
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
CE
Core Router
Eth20
P
P
CE
Core Router
CE
Core Router
P
P
Center node
C-POP
(강남)
A-POP
(영동)
C-POP
(대전)
C-POP
(광주)
C-POP
(대구)
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
PE1
PE2
PE3
vc label 201
vc label 102
vc label 301
vc label 103
vc label 203
vc label 302
MTU-Metro
CE
l3_switch_blue
Core Router
Eth10
Eth11
Eth30
A PW (PE2-PE1)
A PW (PE2-PE3)
A PW (PE2-PE1)
l3_switch_blue
PE1
4 port Bridge

6
Data Forwarding (VPLS MAC Learning): (1)
MTU-Metro
MTU-Metro
MTU-Metro
CE
Core Router
Eth20
P
CE
Core Router
CE
Core Router
P
l3_switch_blue
l3_switch_blue
PE1
PE2
PE3
vc label 201
vc label 301
MTU-Metro
CE
l3_switch_blue
Core Router
Eth10
Eth11
Eth30
vc label 102
vc label 103
vc label 203
vc label 302
IP
M2
M1
SA  DA
1. PE2에Port 20을통해Ethernet frame이들어오면, PE2는frame이들어온물리적인Port (또는Port + VLAN ID)를통해이frame이VPLS 1000에속핚프레임을알아낸다.
: Port or (Port + VLAN ID) .VPLS ID/FIB
IP
M2
M1
Ethernet frame
Destination MAC address
Source MAC address
1.1 Source MAC learning: PE2는도착핚프레임의source MAC address를학습하여SA=M2를VPLS 1000의FIB (Forwarding Information Base)의Eth20에등록핚다.
M2
M1
M3
FIB for VPLS 1000

MAC
Location
Interface

Local
Eth20

Remote
Tunnel to PE1 (vc-lsp201)

Remote
Tunnel to PE3 (vc-lsp203)

M2
1.1

7
Data Forwarding (VPLS MAC Learning): (2)
MTU-Metro
MTU-Metro
MTU-Metro
CE
Core Router
Eth20
P
CE
Core Router
CE
Core Router
P
l3_switch_blue
l3_switch_blue
PE1
PE2
PE3
vc label 201
vc label 301
MTU-Metro
CE
l3_switch_blue
Core Router
Eth10
Eth11
Eth30
vc label 102
vc label 103
vc label 203
vc label 302
IP
M2
M1
SA  DA
M2
M1
M3
1.2 Destination MAC lookup: VPLS 1000의FIB를lookup핚다. Destination MAC = M1이FIB entry에없으면(즉, 학습이되어있지않으면-Unknown frame이면), VPLS 1000에속핚모든PE로프레임을flooding핚다. 즉, 도착핚프레임을복제(replication)하여vc-lsp201를통해PE1으로, vc-lsp 203를통해PE3로전달핚다. (물롞PE4로는전달하지않는다.) 이때vc-label과tunnel label을부착하여전달핚다.
IP
M2
M1
201
Tunnel
Label
L2H
IP
M2
M1
203
Tunnel
Label
L2H
IP
M2
M1
201
Tunnel
Label
L2H
VC Label (Demultiplexor)
Tunnel Label
Transport Header
MPLS frame
FIB for VPLS 1000

MAC
Location
Interface

M2
Local
Eth20

Remote
Tunnel to PE1 (vc-lsp201)

Remote
Tunnel to PE3 (vc-lsp203)


8
Data Forwarding (VPLS MAC Learning): (3)
MTU-Metro
MTU-Metro
MTU-Metro
CE
Core Router
Eth20
P
CE
Core Router
CE
Core Router
P
l3_switch_blue
l3_switch_blue
PE1
PE2
PE3
vc label 201
vc label 301
MTU-Metro
CE
l3_switch_blue
Core Router
Eth10
Eth11
Eth30
vc label 102
vc label 103
vc label 203
vc label 302
M2
M1
M3
IP
M2
M1
201
Tunnel
Label
L2H
IP
M2
M1
203
Tunnel
Label
L2H
IP
M2
M1
201
Tunnel
Label
L2H
VC Label (Demultiplexor)
Tunnel Label
Transport Header
MPLS frame
2. Core LSRs (P Routers): PW상의모든LSR들은Outer label (Tunnel label)값만참조하여해당PE까지프레임을전달핚다(label swapping). LSR들은Tunnel label값만참조하여포워딩하기때문에현재자기가포워딩하고있는프레임들이어느VPLS에속핚프레임인지는모른다.
router_blue
router_blue
router_blue
router_blue

9
Data Forwarding (VPLS MAC Learning): (4)
MTU-Metro
MTU-Metro
MTU-Metro
CE
Core Router
Eth20
P
CE
Core Router
CE
Core Router
P
l3_switch_blue
l3_switch_blue
PE1
PE2
PE3
vc label 201
vc label 301
MTU-Metro
CE
l3_switch_blue
Core Router
Eth10
Eth11
Eth30
vc label 102
vc label 103
vc label 203
vc label 302
M2
M1
M3
IP
M2
M1
201
Tunnel
Label
L2H
IP
M2
M1
203
Tunnel
Label
L2H
FIB for VPLS 1000

MAC
Location
Interface

Local
Eth10

Local
Eth11

Remote
Tunnel to PE2 (vc-lsp102)

Remote
Tunnel to PE3 (vc-lsp103)

3. PE1 (Egress LER): PE1는도착핚프레임의vc-label값을참조하여이프레임이어느VPLS에속핚프레임인지를알아낸다(이예에서는VPLS 1000에속핚프레임임을알게된다). : vc-label lookup .VPLS ID/FIB
3.1 Source MAC learning: 도착핚MPLS 프레임의label를제거(POP)하고이더넷프레임의source MAC address를학습핚다. PE1은M2가vc-label 201를통해서왔으므로M2가PE2뒤에있음을알게된다. 따라서, M2를vc-label102 인터페이스에학습시킨다. PE3도동일핚동작을수행핚다.
M2
3.1
MAC
Location
Interface

Local
Eth30

Remote
Tunnel to PE1 (vc-lsp301)

Remote
Tunnel to PE2 (vc-lsp302)

FIB for VPLS 1000
M2
3.1

10
Data Forwarding (VPLS MAC Learning): (5)
MTU-Metro
MTU-Metro
MTU-Metro
CE
Core Router
Eth20
P
CE
Core Router
CE
Core Router
P
l3_switch_blue
l3_switch_blue
PE1
PE2
PE3
vc label 201
vc label 301
MTU-Metro
l3_switch_blue
Eth10
Eth11
Eth30
vc label 102
vc label 103
vc label 203
vc label 302
M2
M1
MAC
Location
Interface

Local
Eth30

Remote
Tunnel to PE1 (vc-lsp301)

M2
Remote
Tunnel to PE2 (vc-lsp302)

FIB for VPLS 1000
3.2 Destination MAC lookup: DA=M1이VPLS 1000의FIB에학습이되어있지않으므로VPLS 1000에속핚모든Port로이더넷프레임을flooding핚다(이예에서는Eth10, Eth11로전달된다). 이때loop 방지를위해vc-lsp에서온프레임은VPLS에속핚다른vc-lsp로flooding하지않는다. (split-horizon rule). 즉, vc-lsp301로는flooding하지않는다.
IP
M2
M1
IP
M2
M1
IP
M2
M1
CE
Core Router
M3
FIB for VPLS 1000

MAC
Location
Interface

Local
Eth10

Local
Eth11

M2
Remote
Tunnel to PE2 (vc-lsp102)

Remote
Tunnel to PE3 (vc-lsp103)


11
Data Forwarding (VPLS MAC Learning): (6)
MTU-Metro
MTU-Metro
MTU-Metro
CE
Core Router
Eth20
P
CE
Core Router
CE
Core Router
P
l3_switch_blue
l3_switch_blue
PE1
PE2
PE3
vc label 201
vc label 301
MTU-Metro
l3_switch_blue
Eth10
Eth11
Eth30
vc label 102
vc label 103
vc label 203
vc label 302
M2
M1
CE
Core Router
M3
4. M1 reply: Site 1의station 1이reply를하여DA=M2, SA=M1인이더넷프레임을PE1으로전달핚다.
IP
M1
M2
FIB for VPLS 1000

MAC
Location
Interface

Local
Eth10

Local
Eth11

M2
Remote
Tunnel to PE2 (vc-lsp102)

Remote
Tunnel to PE3 (vc-lsp103)

5. PE1에Port 10을통해Ethernet frame이들어오면, PE1는frame이들어온물리적인Port (또는Port + VLAN ID)를통해이frame이VPLS 1000에속핚프레임을알아낸다.
5.1 Source MAC learning: PE1는도착핚프레임의source MAC address를학습하여SA=M1를VPLS 1000의FIB (Forwarding Information Base)의Eth10에등록핚다.
M1
5.1
M4

12
Data Forwarding (VPLS MAC Learning): (7)
MTU-Metro
MTU-Metro
MTU-Metro
CE
Core Router
Eth20
P
CE
Core Router
CE
Core Router
P
l3_switch_blue
l3_switch_blue
PE1
PE2
PE3
vc label 201
vc label 301
MTU-Metro
l3_switch_blue
Eth10
Eth11
Eth30
vc label 102
vc label 103
vc label 203
vc label 302
M2
M1
CE
Core Router
M3
IP
M1
M2
FIB for VPLS 1000

MAC
Location
Interface

M1
Local
Eth10

Local
Eth11

M2
Remote
Tunnel to PE2 (vc-lsp102)

Remote
Tunnel to PE3 (vc-lsp103)

5.2 Destination MAC lookup: PE1은이더넷프레임의destination MAC address를VPLS 1000의FIB에서Lookup핚다. M2가학습되어있으므로vc-lsp102을통해프레임을전달(Unicast)핚다.
IP
M1
M2
102
Tunnel
Label
L2H

13
Data Forwarding (VPLS MAC Learning): (8)
MTU-Metro
MTU-Metro
MTU-Metro
CE
Core Router
Eth20
P
CE
Core Router
CE
Core Router
P
l3_switch_blue
l3_switch_blue
PE1
PE2
PE3
vc label 201
vc label 301
FIB for VPLS 1000

MAC
Location
Interface

M2
Local
Eth20

Remote
Tunnel to PE1 (vc-lsp201)

Remote
Tunnel to PE3 (vc-lsp203)

MTU-Metro
CE
l3_switch_blue
Core Router
Eth10
Eth11
Eth30
FIB for VPLS 1000

MAC
Location
Interface

Local
Eth30

Remote
Tunnel to PE1 (vc-lsp301)

M2
Remote
Tunnel to PE2 (vc-lsp302)

vc label 102
vc label 103
vc label 203
vc label 302
FIB for VPLS 1000

MAC
Location
Interface

M1
Local
Eth10

Local
Eth11

M2
Remote
Tunnel to PE2 (vc-lsp102)

Remote
Tunnel to PE3 (vc-lsp103)

6. PE2는SA=M1을학습하여FIB entry(vc-lsp201)에등록하고, DA=M2는학습이되어있으므로Eth20 port를통해포워딩핚다.
IP
M1
M2
102
Tunnel
Label
L2H
IP
M1
M2
M2
M1
M3
M1
6

14
Data Forwarding (VPLS MAC Learning): (9)
MTU-Metro
MTU-Metro
MTU-Metro
CE
Core Router
Eth20
P
CE
Core Router
CE
Core Router
P
l3_switch_blue
l3_switch_blue
PE1
PE2
PE3
vc label 201
vc label 301
FIB for VPLS 1000

MAC
Location
Interface

M2
Local
Eth20

M1, M3
Remote
Tunnel to PE1 (vc-lsp201)

M4
Remote
Tunnel to PE3 (vc-lsp203)

MTU-Metro
CE
l3_switch_blue
Core Router
Eth10
Eth11
Eth30
FIB for VPLS 1000

MAC
Location
Interface

M4
Local
Eth30

M1, M3
Remote
Tunnel to PE1 (vc-lsp301)

M2
Remote
Tunnel to PE2 (vc-lsp302)

vc label 102
vc label 103
vc label 203
vc label 302
FIB for VPLS 1000

MAC
Location
Interface

M1
Local
Eth10

M3
Local
Eth11

M2
Remote
Tunnel to PE2 (vc-lsp102)

M4
Remote
Tunnel to PE3 (vc-lsp103)

M2
M1
M3
M4
7. 몇번의Unknown frame들이flooding 방식으로오고가면, 각PE의VPLS 1000의FIB table은아래와같이MAC entry들이등록되게된다.

15
Data Forwarding (VPLS MAC Learning): (10)
MTU-Metro
MTU-Metro
MTU-Metro
CE
Core Router
Eth20
P
CE
Core Router
CE
Core Router
P
l3_switch_blue
l3_switch_blue
PE1
PE2
PE3
vc label 201
vc label 301
FIB for VPLS 1000

MAC
Location
Interface

M2
Local
Eth20

M1, M3
Remote
Tunnel to PE1 (vc-lsp201)

M4
Remote
Tunnel to PE3 (vc-lsp203)

MTU-Metro
CE
l3_switch_blue
Core Router
Eth10
Eth11
Eth30
FIB for VPLS 1000

MAC
Location
Interface

M4
Local
Eth30

M1, M3
Remote
Tunnel to PE1 (vc-lsp301)

M2
Remote
Tunnel to PE2 (vc-lsp302)

vc label 102
vc label 103
vc label 203
vc label 302
FIB for VPLS 1000

MAC
Location
Interface

M1
Local
Eth10

M3
Local
Eth11

M2
Remote
Tunnel to PE2 (vc-lsp102)

M4
Remote
Tunnel to PE3 (vc-lsp103)

M2
M1
M3
M4
8. 이후의프레임전달과정은destination MAC address가모두학습되어있으므로flooding되지않고바로unicast로포워딩된다.
IP
M2
M3
IP
M2
M3
201
Tunnel
Label
L2H
IP
M2
M3

16
Data Forwarding (VPLS MAC Learning): (11)
MTU-Metro
MTU-Metro
MTU-Metro
CE
Core Router
Eth20
P
CE
Core Router
CE
Core Router
P
PE1
PE2
PE3
vc label 201
MTU-Metro
CE
Core Router
Eth10
Eth30
FIB for VPLS 1000

MAC
Location
Interface

M1
Local
Eth10

M3
Local
Eth11

M2
Remote
Tunnel to PE2 (vc-lsp102)

M4
Remote
Tunnel to PE3 (vc-lsp103)

M2
M1
M3
M4
vc label 102
vc label 103
vc label 301
vc label 302
vc label 203
vc label 21
vc label 12
vc label 31
vc label 13
vc label 13
vc label 31
CE
M11
Eth11
l3_switch_blue
Eth12
CE
Eth31
CE
l3_switch_blue
l3_switch_blue
Eth21
1107378_L1
M12
1107378_L1
M13
1107378_L1
M14
1107378_L1
M31
1107378_L1
M32
1107378_L1
M33
1107378_L1
M34
1107378_L1
M21
1107378_L1
M22
1107378_L1
M23
1107378_L1
M24
1107378_L1
FIB for VPLS 1000

MAC
Location
Interface

M4
Local
Eth30

M1, M3
Remote
Tunnel to PE1 (vc-lsp301)

M2
Remote
Tunnel to PE2 (vc-lsp302)

FIB for VPLS 1000

MAC
Location
Interface

M2
Local
Eth20

M1, M3
Remote
Tunnel to PE1 (vc-lsp201)

M4
Remote
Tunnel to PE3 (vc-lsp203)

FIB for VPLS 2000

MAC
Location
Interface

M21, M22, M23, M24
Local
Eth20

M11, M12, M13, M14
Remote
Tunnel to PE1 (vc-lsp21)

M31, M32, M33, M34
Remote
Tunnel to PE3 (vc-lsp23)

FIB for VPLS 2000

MAC
Location
Interface

M11, M12, M13, M14
Local
Eth20

M21, M22, M23, M24
Remote
Tunnel to PE2 (vc-lsp12)

M31, M32, M33, M34
Remote
Tunnel to PE3 (vc-lsp13)

FIB for VPLS 2000

MAC
Location
Interface

M31, M32, M33, M34
Local
Eth20

M11, M12, M13, M14
Remote
Tunnel to PE1 (vc-lsp31)

M21, M22, M23, M24
Remote
Tunnel to PE2 (vc-lsp32)

.Customer별로FIB가분리됨.
.CPE가L2인경우Customer PC MAC이PE에서모두Learning됨.

17
Data Forwarding (VPLS MAC Learning): (12)
MTU-Metro
MTU-Metro
MTU-Metro
CE
Core Router
CE
Core Router
CE
Core Router
MTU-Metro
CE
Core Router
FIB for VPLS 1000

MAC
Location
Interface

M1
Local
Eth10

M3
Local
Eth11

M2
Remote
Tunnel to PE2 (vc-lsp102)

M4
Remote
Tunnel to PE3 (vc-lsp103)

M2
M1
M3
M4
CE
M11
CE
CE
1107378_L1
M12
1107378_L1
M13
1107378_L1
M14
1107378_L1
M31
1107378_L1
M32
1107378_L1
M33
1107378_L1
M34
1107378_L1
M21
1107378_L1
M22
1107378_L1
M23
1107378_L1
M24
1107378_L1
FIB for VPLS 1000

MAC
Location
Interface

M4
Local
Eth30

M1, M3
Remote
Tunnel to PE1 (vc-lsp301)

M2
Remote
Tunnel to PE2 (vc-lsp302)

FIB for VPLS 1000

MAC
Location
Interface

M2
Local
Eth20

M1, M3
Remote
Tunnel to PE1 (vc-lsp201)

M4
Remote
Tunnel to PE3 (vc-lsp203)

FIB for VPLS 2000

MAC
Location
Interface

M21, M22, M23, M24
Local
Eth20

M11, M12, M13, M14
Remote
Tunnel to PE1 (vc-lsp21)

M31, M32, M33, M34
Remote
Tunnel to PE3 (vc-lsp23)

FIB for VPLS 2000

MAC
Location
Interface

M11, M12, M13, M14
Local
Eth20

M21, M22, M23, M24
Remote
Tunnel to PE2 (vc-lsp12)

M31, M32, M33, M34
Remote
Tunnel to PE3 (vc-lsp13)

FIB for VPLS 2000

MAC
Location
Interface

M31, M32, M33, M34
Local
Eth20

M11, M12, M13, M14
Remote
Tunnel to PE1 (vc-lsp31)

M21, M22, M23, M24
Remote
Tunnel to PE2 (vc-lsp32)

.각Customer Site가Customer별로독립적인L2 SW에연결되어있는것과등가임.
L2 SW for Customer X
L2 SW for Customer Y
VPLS Network

18
VPLS VPN에서MAC Learning의범위
MTU-Metro
MTU-Metro
MTU-Metro
MTU-Metro
l3_switch_orange
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
MTU-Metro
PE
CE
Core Router
CE
Core Router
Port
VLAN
QinQ (C-VID/S-VID)
P
P
l3_switch_orange
CE
Core Router
CE
Core Router
VLAN
QinQ (C-VID/S-VID)
PE
CE
Core Router
P
P
Center node
C-POP
(강남)
A-POP
(영동)
C-POP
(대전)
C-POP
(광주)
C-POP
(대구)
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
PE
A-POP
(송파)
VSI
VSI
VSI
MTU-Metro
CE
Core Router
MTU-Metro
CE
VSI
VSI
VSI
VPLS for Customer A: 1K MACs
VPLS for Customer B: 1K MACs
VPLS for Customer C: 1K MACs
VPLS for Customer D: 1K MACs
VSI
1K
1K
2K
1K
2K
1K
1K
1K
1K
1K
MTU-Metro
CE
VSI
Core Router
MTU-Metro
CE
VSI
1K
MTU-Metro
CE
VSI
Core Router
MTU-Metro
CE
VSI
Core Router
MTU-Metro
CE
VSI
Core Router
MTU-Metro
CE
VSI
Core Router
Core Router
Core Router

19
Multipoint Service Case: Comparison
.CE갂에VLL (EoMPLS)을Full-Mesh로설정함.
.CE는Router이어야함.
.CE갂에는Routing Protocol이돆다.
.각CE의VLAN interface별로IP address를ISP가핛당해준다.
.LAN에서발생핚Packet을어느Site로전달핛것인지를CE가결정함.
.PE에서Customer MAC Learning이필요없다.
.P에서는Customer MAC Learning이필요없다.
.Remote Site 추가시, 모든CE에VLAN추가, IP Interface추가, RT에NextHop 추가(Static)
.각CE는PE와단일Interface (Port or VLAN)만설정된다.
.CE로부터유입된Frame을어느Site로전달해야핛지는ISP의PE가결정핚다.
.PE에서Customer MAC Learning이필요하다.
.P에서는Customer MAC Learning이필요없다.
.CE는L3 Router이어도되고L2 Switch이어도된다.
.CE가router인경우
.CE갂에는Routing Protocol이돌거나Static.
.각CE의단일interface에IP address를ISP가핛당해준다.
.Remote Site 추가시각CE에는RT에싞규Site에대핚NextHop만추가
.PE에서는CE의MAC만Learning
.CE가Switch인경우
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
Core Router
Core Router
Core Router
Core Router
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
CE1
CE2
CE3
CE4
CE5
PE
PE
PE
PE
PE
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
Core Router
Core Router
Core Router
Core Router
Core Router
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
CE1
CE2
CE3
CE4
CE5
PE
PE
PE
PE
PE
PW
VPLS
VLAN 100
VLAN 101
VLAN 102
VLAN 103
VLAN 200
VLAN 201
VLAN 202
VLAN 203
VLAN 300
VLAN 301
VLAN 302
VLAN 303
VLAN 400
VLAN 401
VLAN 402
VLAN 403
VLAN 500
VLAN 501
VLAN 502
VLAN 503
Core Router
EoMPLS
VPLS

20
Loop Prevention: Split-Horizon
MTU-Metro
MTU-Metro
MTU-Metro
CE
Core Router
Eth20
P
CE
Core Router
CE
Core Router
P
l3_switch_blue
l3_switch_blue
PE1
PE2
PE3
vc label 201
vc label 301
MTU-Metro
CE
l3_switch_blue
Core Router
Eth10
Eth11
Eth30
vc label 102
vc label 103
vc label 203
vc label 302
M2
M1
M3
M4
VSI
VSI
VSI
1에서언급핚바와같이, 하나의VPN에속핚모든PE들갂에는VCs이Full-mesh로생성핚다. 즉, 모든PE에서다른PE 로는1 HOP으로전달된다. 이때Split-Horizon forwarding rule을적용하여loop를방지핚다.
Split-Horizon forwarding rule: PW-to-another PW 포워딩을금지

21
VPLS Drawbacks
.PW Scalability: O(N2)
.PE Frame Replication (Not P)
.Add A New Site
.Customer MAC Learning at PE

22
VPLS Scalability Issues (1): PW Scalability (IP over ATM망에서와똑같은이슈임)
P
P
l3_switch_blue
l3_switch_blue
CE1
Core Router
P
CE7
Core Router
CE5
Core Router
P
Center node
C-POP
(강남)
A-POP
(영동)
C-POP
(대전)
C-POP(광주)
C-POP
(대구)
A-POP
(송파)
CE8
Core Router
CE2
Core Router
CE3
Core Router
CE4
Core Router
CE6
Core Router
l3_switch_blue
l3_switch_blue
P
l3_switch_blue
l3_switch_blue
PE7
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
PE3
PE2
PE9
PE1
l3_switch_blue
l3_switch_blue
PE5
PE4
PE10
PE8
PE6
PE n
.m: # of MAC Addresses by Service Instance
.s: # of Service Instances
.n: # of PE Routers
.Total Number of MAC addresses = m*s
.Number of LDP session per PE = n-1
.Total Number of Tunnel LSP = n*(n-1)
.Total Number of PW = n * (n-1)/2 * s
.m: 1K
.s: 1,000
.n: 100
.Total Number of MAC addresses = 1,000,000
.Number of LDP session per PE = 99
.Total Number of Tunnel LSP = 9,900
.Total Number of PW = 4,950,000 (> 1,048,576: 220)
하나의VPLS VPN에속한PE들간에
Full-Mesh PWs

23
VPLS Scalability Issues (2): PE packet replication
P
P
l3_switch_blue
l3_switch_blue
CE
Core Router
P
CE
Core Router
CE
Core Router
P
Center node
C-POP
(강남)
A-POP(영동)
C-POP(대전)
C-POP
(광주)
C-POP
(대구)
A-POP
(송파)
CE
Core Router
CE
Core Router
CE
Core Router
CE
Core Router
CE
Core Router
l3_switch_blue
l3_switch_blue
P
l3_switch_blue
l3_switch_blue
PE
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
PE
PE
PE
PE
l3_switch_blue
Ex. Unknown MAC Flooding

24
VPLS Scalability Issues (3): Add A New Site
P
P
l3_switch_blue
l3_switch_blue
CE
Core Router
P
CE
Core Router
CE
Core Router
P
Center node
C-POP
(강남)
A-POP
(영동)
C-POP
(대전)
C-POP(광주)
C-POP
(대구)
A-POP
(송파)
CE
Core Router
CE
Core Router
CE
Core Router
CE
Core Router
CE
Core Router
l3_switch_blue
l3_switch_blue
P
l3_switch_blue
l3_switch_blue
PE
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
PE
PE
PE
PE
l3_switch_blue
PW
MTU-Metro
CE
l3_switch_blue
Core Router
New Site
PE
PE
PE
PE

25
MTU-Metro
MTU-Metro
MTU-Metro
MTU-Metro
H-VPLS
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
CE
Core Router
Port
VLAN
QinQ (C-VID/S-VID)
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
P
l3_switch_orange
CE
Core Router
CE
Core Router
VLAN
QinQ (C-VID/S-VID)
uPE
CE
Core Router
P
Center node
C-POP
(강남)
A-POP
(영동)
C-POP
(대전)
C-POP
(광주)
C-POP
(대구)
A-POP
(송파)
uPE
uPE
uPE
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
nPE
nPE
nPE
AC
Spoke PW
Hub PW
AC
Spoke PW
VSI
AC
VSI
VSI
VSI
VSI
Virtual Switch Instance (MAC Learning)
Core Router
VSI
VSI
VSI
VSI
VSI
Core Router
VSI
VSI
VSI
Core Router
H-VPLS was invented to eliminate the PW mesh scaling issues

26
H-VPLS Scalability (1): Full-Mesh Problem
P
P
l3_switch_blue
l3_switch_blue
CE
Core Router
P
CE
Core Router
CE
Core Router
P
Center node
C-POP
(강남)
A-POP
(영동)
C-POP
(대전)
C-POP
(광주)
C-POP
(대구)
A-POP
(송파)
CE
Core Router
CE
Core Router
CE
Core Router
CE
Core Router
CE
Core Router
l3_switch_blue
l3_switch_blue
CE
Core Router
P
CE
Core Router
CE
Core Router
P
Center node
C-POP
(강남)
A-POP
(영동)
C-POP
(대전)
C-POP
(광주)
C-POP
(대구)
A-POP
(송파)
uPE
CE
Core Router
CE
Core Router
CE
Core Router
CE
Core Router
CE
Core Router
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
uPE
uPE
uPE
l3_switch_blue
uPE
l3_switch_blue
l3_switch_blue
P
l3_switch_blue
l3_switch_blue
PE
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
PE
PE
PE
PE
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
nPE
nPE
nPE
uPE
uPE
uPE
nPE
Spoke PW
Full-Mesh PW
l3_switch_blue
PE
PE
PE
PE
l3_switch_blue
Hub PW
(Full Mesh)
AC
VPLS
H-VPLS

27
H-VPLS Scalability (2): Forwarding Plane
P
P
l3_switch_blue
l3_switch_blue
CE
Core Router
P
CE
Core Router
CE
Core Router
P
Center node
C-POP
(강남)
A-POP
(영동)
C-POP
(대전)
C-POP
(광주)
C-POP
(대구)
A-POP
(송파)
CE
Core Router
CE
Core Router
CE
Core Router
CE
Core Router
CE
Core Router
l3_switch_blue
l3_switch_blue
CE
Core Router
P
CE
Core Router
CE
Core Router
P
Center node
C-POP
(강남)
A-POP
(영동)
C-POP
(대전)
C-POP
(광주)
C-POP
(대구)
A-POP
(송파)
uPE
CE
Core Router
CE
Core Router
CE
Core Router
CE
Core Router
CE
Core Router
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
uPE
uPE
uPE
l3_switch_blue
uPE
l3_switch_blue
l3_switch_blue
P
l3_switch_blue
l3_switch_blue
PE
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
PE
PE
PE
PE
l3_switch_blue
Ex. Unknown MAC Flooding
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
nPE
nPE
nPE
uPE
uPE
uPE
nPE
AC
Spoke PW
Hub PW
PW
VPLS
H-VPLS

28
H-VPLS Scalability (3): Adding a New Site
P
P
l3_switch_blue
l3_switch_blue
CE
Core Router
P
CE
Core Router
CE
Core Router
P
Center node
C-POP
(강남)
A-POP
(영동)
C-POP
(대전)
C-POP
(광주)
C-POP
(대구)
A-POP
(송파)
CE
Core Router
CE
Core Router
CE
Core Router
CE
Core Router
CE
Core Router
l3_switch_blue
l3_switch_blue
CE
Core Router
P
CE
Core Router
CE
Core Router
P
Center node
C-POP
(강남)
A-POP
(영동)
C-POP
(대전)
C-POP
(광주)
C-POP
(대구)
A-POP
(송파)
uPE
CE
Core Router
CE
Core Router
CE
Core Router
CE
Core Router
CE
Core Router
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
uPE
uPE
uPE
l3_switch_blue
uPE
l3_switch_blue
l3_switch_blue
P
l3_switch_blue
l3_switch_blue
PE
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
PE
PE
PE
PE
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
nPE
nPE
nPE
uPE
uPE
uPE
nPE
Spoke PW
PW
MTU-Metro
CE
l3_switch_blue
Core Router
New Site
PE
PE
PE
PE
MTU-Metro
CE
New Site
l3_switch_blue
Core Router
Hub PW
VPLS
H-VPLS

29
VPLS vs. H-VPLS
Limitation of H-VPLS scheme: nPE (PE-rs/Hub PE)가Learning해야핛MAC address의수는nPE하단의uPE (MTU-s/Spoke PE)에서Learning하는MAC address의합과같다.
MTU-Metro
CE
Core Router
MTU-Metro
CE
Core Router
MTU-Metro
CE
MTU-Metro
CE
Core Router
MTU-Metro
CE
Core Router
MTU-Metro
CE
Core Router
MTU-Metro
CE
Core Router
Core Router
MTU-Metro
MTU-Metro
MTU-Metro
MTU-Metro
l3_switch_orange
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
MTU-Metro
uPE
CE
Core Router
CE
Core Router
VLANQinQ (C-VID/S-VID)
P
P
l3_switch_orange
CE
Core Router
CE
Core Router
VLAN
QinQ (C-VID/S-VID)
uPE
CE
Core Router
P
Center node
C-POP
(강남)
A-POP
(영동)
C-POP
(대전)
C-POP
(광주)
C-POP
(대구)
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
l3_switch_blue
uPE
A-POP(송파)
VSI
VSI
MTU-Metro
CE
Core Router
MTU-Metro
CE
VSI
VSI
VSI
VPLS for Customer A: 1K MACs
VPLS for Customer B: 1K MACs
VPLS for Customer C: 1K MACs
VPLS for Customer D: 1K MACs
VSI
1K
1K
1K
2K
1K
2K
1K
1K
1K
VSI
1K
1K
3K
nPE
uPE
3K
4K
3K
VSI
VSI
nPE
VSI
Core Router
VSI
VSI
MTU-Metro
CE
Core Router
VSI