netmanias EoMPLS기술
2001년4월27일
손장우
010-3460-5747
02-3444-5747
https://www.netmanias.com, son@netmanias.com
www.netmanias.com
2
Problem of VLAN-based TLS
SwitchATMFastEthr
SwitchATMFastEthr
SwitchATMFastEthr
SwitchATMFastEthr
SwitchATMFastEthr
SwitchATMFastEthr
SwitchATMFastEthr
router-generic
router-generic
router-generic
router-generic
router-generic
router-generic
router-generic
router-generic
CPE
SwitchATMFastEthr
Ingress Rate Limiting/Shaping
100
100
100
100
100
100
802.1q tagged VLAN 설정
A Broadcast Domain over
Metro Ethernet Network
#NAME?
802.1p CoS 제공
= Classification, Marking,  Priority queueing and scheduling
ESP network
.VLAN space limitation: 4096 VLANs (VLAN ID=12bits)
.MAC address limitation
.No Bandwidth reservation in metro core (end-to-end)
.No traffic engineering in metro core (STP Path)
.Slow restoration time (STP, RSTP, EAPS)
MAC     VLAN type   VLAN ID         Port
-tagged        100               1, 2
-tagged        200               1, 3
……….
A                                                       2  
B                                                       1
C                                                       2
……….
MAC A
MAC F
MAC B
MAC C
MAC M
MAC N
MAC G
MAC H
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3
EoMPLS
MTU-Metro
MTU-Metro
Optical Router
Core Router
Optical Router
Optical Router
Core Router
Core Router
Core Router
Core Router
CE
CE
CE
CE
CE
Optical Router
Optical Router
Optical Router
A
D
B
F
E
.VLAN의확장성한계, MAC learning 한계, QoS, BW 예약, 망복구능력등의문제에대한대안으로써Metro Ethernet에MPLS를도입함.
PE
P
P
PE
PE
P
Tunnel LSP
Ingress LER (PE)과Egress LER (PE)간에두개의LSP (Label Switched Path)를설정.Tunnel LSP: 두PEs간에MPLS frame을forwarding. Customer 구분없이MPLS망상에서경로만제공. ATM의VP (Virtual Path)개념. Tunnel LSP내에여러개의VC(Virtual Circuit)들이전달됨.
.VC LSP: Egress LER에서Tunnel LSP로들어오는패킷들이어느가입자의패킷이며, 또어떻게처리(어느outgoing interface로포워딩해주어야하는가, 등)해주어야하는가를결정하기위해서Tunnel LSP내에VC LSP가정의된다. ATM의VC개념. (for de-multiplexing senders.). VC label은LSR에서는안보이고Egress LER에서만보인다.
VC LSP
.Metro Ethernet Network의Edge (LER)에서Ethernet frame을MPLS lsp로mapping
(not Routing)
Ethernet
Or VLAN
Ethernet
Or VLAN
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4
catalyst
EoMPLS Operation
MTU-Metro
MTU-Metro
Optical Router
Core Router
Optical Router
Optical Router
Core Router
Core Router
Core Router
Core Router
CE
CE
CE
CE
CE
Optical Router
Optical Router
Optical Router
A
D
B
F
E
PE
P
P
PE
PE
P
Eth
10
25
Eth
Eth
10
35
Eth
10
17
Eth
Eth
Eth
20
25
Eth
20
35
Eth
20
17
Eth
Port   VLAN ID  outgoing port    Tunnel Label    VC Label
1             -3                      25                     10
2         100              3                      25                      20
1
2
L2
3
Incoming port   VC Label         outgoing port
1                   10                    5
1                   20                    6
Incoming port  Tunnel Label   outgoing port    Tunnel Label
3                   25                          4                35
4
1
5
6
Forwarding table
Forwarding table
Forwarding table
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5
catalyst
EoMPLS의장점
MTU-Metro
MTU-Metro
Optical Router
Core Router
Optical Router
Optical Router
Core Router
Core Router
Core Router
Core Router
CE
CE
CE
CE
CE
Optical Router
Optical Router
Optical Router
A
D
B
F
E
PE
P
P
PE
PE
P
Eth
10
25
Eth
Eth
10
35
Eth
10
17
Eth
Eth
Eth
20
25
Eth
20
35
Eth
20
17
Eth
Port   VLAN ID  outgoing port    Tunnel Label    VC label Label
1             -3                      25                     10
2         100              3                      25                      20
1
2
L2
3
Incoming port   VC Label         outgoing port
1                   10                    5
1                   20                    6
Incoming port  Tunnel Label   outgoing port    Tunnel Label
3                   25                          4                35
4
1
5
6
Forwarding table
Forwarding table
Forwarding table
Metro (또는WAN) core의LSR들은단지Tunnel Label값만보고MPLS frame을포워딩한다. 따라서Metro core에서는가입자측의MAC address를학습할필요가없다.
Ingress LER은Ethernet망에서들어오는Frame을{Physical port and 802.1q VLAN ID}값만참조하여어느VC-LSP로포워딩할것인지를판단한다.
따라서, Egress LER쪽의가입자의MAC address를학습하지않는다.
Egress LER은VC label값만을이용하여포워딩결정을내린다. 따라서, 가입자측의MAC address를학습하지않아도된다.
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6
EoMPLS: Martini Signaling
구름
구름
Eth-Frame
구름
router
router
router
CE1
router
CE2
PE1
PE2
Eth/10
VLAN/100
Eth/20
VLAN/200
Configuration
Interface: Eth/20 VLAN/200
VC ID (=L2-FEC): 3001
Map Eth/20 VLAN/200 VCID 3001
VC label: 2000
Peer Router: 10.0.0.1
Targeted LDP
Configuration
Interface: Eth/10 VLAN/100
VC ID (=L2-FEC): 3001
Map Eth/10 VLAN/100 VCID 3001
VC label: 4000
Peer Router: 10.0.0.2
10.0.0.2
10.0.0.1
Label mapping msg (DU-LDP)
VC FEC TLV
VC Type = Ethernet
VC ID = 3001
VC label TLV
VC label = 2000
Label mapping msg (DU-LDP)
VC FEC TLV
VC Type = Ethernet
VC ID = 3001
VC label TLV
VC label = 4000
Eth-Frame
2000
100
L2H
Eth-Frame
Tunnel LSP
A PW (2 VC lsps) setup !
vc2000
vc4000
VLAN/100
Eth/10
VLAN/200
Eth/20
PW = VLL
Site 2가PE2의Ethernet port 20에VLAN ID 200의Ethernet circuit에붙어있다.
Site 2로보내려면Label 2000을붙여서보내라
Site 2
Site 1
VCID
In
Out

3001
VC label 4000
Eth/10 VLAN/100

Eth/10 VLAN/100
?

VCID
In
Out

3001
VC label 4000
Eth/10 VLAN/100

Eth/10 VLAN/100
2000

VCID
In
Out

3001
VC label 2000
Eth/20 VLAN/200

Eth/20 VLAN/200
?

VCID
In
Out

3001
VC label2000
Eth/20 VLAN/200

Eth/20 VLAN/200
4000

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7
MTU-Metro
ERS service using EoMPLS
MTU-Metro
MTU-Metro
Optical Router
Core Router
Optical Router
Optical Router
Core Router
Core Router
CE
Optical Router
Optical Router
Optical Router
PE
P
P
PE
PE
Tagged VLAN
100
Tagged VLAN
101
Subnet 1 (192.182.10/24)
HQ site Router
One subnet for each remote site
Subnet 2 (192.182.20/24)
CE (L2 SW)
CE (L2 SW)
PE는port #와VLAN ID만을가지고어느VC-LSP로포워딩할것인지를결정하기떄문에VLAN Tag를달고들어오지않으면Site 2로포워딩할지Site 3으로포워딩할지를판단할수없다.
따라서, Site 1의CE가Site별로구분된VLAN Tag를달아서보내야한다.
Site 2와Site 3간의통신을위해서는CE가반드시라우터이어야한다.