· MPLS = WAN Technology
· MPLS = Multi Protocol Label Switching
· Extend to multiple protocols : Layer 2 protocols (HDLC,
PPP, ...) and Layer 3 protocols (IPv4, IPv6, ...)
· Based on the label switching
· Label is a tag or integer associated with the packets in
the MPLS network. The MPLS use it to make a routing decisions.
·
· MPLS Objectives :
· Increase the transfer speed
· Combine the layer 2 protocols and layer 3 protocols
· Traffic engineering
· Flexibility
·
· MPLS Packet : L2 Header + MPLS Header + L3
Header + DATA
·
· MPLS Header : Label + EXP + S + TTL
· Label = 20 bits : Integer to be used for the routing
decisions
· EXP = 3 bits : For the QOS
· S = 1 bit : To support the hierarchical label
· TTL = 8 bits : To avoid the loops
·
· MPLS Operations : See the Picture 1
·
· MPLS Configuration : See the Picture 2
· Basic Configuration :
- Hostname
- Addressing (Backbone interfaces)
- Routing (Backbone zone) : OSPF 1
area 0
· Test :
- PING from PE1 to PE2/PE3
# ping 20.20.20.20 # ping 30.30.30.30
- Routing Table :
# show ip route ospf | begin Gateway
· LDP Configuration :
- LDP = Label Distributed Protocol
- LDP = MPLS
#router ospf 1
#mpls ldp autoconfig
#exit
· Test :
#do show mpls interfaces
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#do show mpls ldp neighbor #do traceroute 20.20.20.20
· MP-BGP :
- PE1 :
router bgp 1
neighbor 20.20.20.20 remote-as 1
neighbor 30.30.30.30 remote-as 1
neighbor 20.20.20.20 update-source lo
0
neighbor 30.30.30.30 update-source lo
0
no auto-summary
address-family vpnv4 unicast
neighbor 20.20.20.20 activate
neighbor 30.30.30.30 activate
exit
exit
- PE2 :
router bgp 1
neighbor 10.10.10.10 remote-as 1
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neighbor 30.30.30.30 remote-as 1
neighbor 10.10.10.10 update-source lo
0
neighbor 30.30.30.30 update-source lo
0
no auto-summary
address-family vpnv4 unicast
neighbor 10.10.10.10 activate
neighbor 30.30.30.30 activate
exit
exit
- PE1 :
router bgp 1
neighbor 20.20.20.20 remote-as 1
neighbor 10.10.10.10 remote-as 1
neighbor 20.20.20.20 update-source lo
0
neighbor 10.10.10.10 update-source lo
0
no auto-summary
address-family vpnv4 unicast
neighbor 20.20.20.20 activate
neighbor 10.10.10.10 activate
exit
exit
· Test :
do show bgp vpnv4 unicast all summary
· VRF Configuration :
- VRF = Virtual Routing Forwarder
- VRF = Allows to create a multiple
instances of a Routing table on the
same router
- PE1 :
ip vrf UITS
rd 1:1
route-target both 1:1
exit
interface GigabitEthernet0/1
no sh
ip vrf forwarding UITS
ip address 11.0.0.1 255.255.255.0
exit
router ospf 1000 vrf UITS
network 11.0.0.0 0.0.0.255 area 1
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exit - PE2 :
ip vrf UITS
rd 1:1
route-target both 1:1
exit
interface GigabitEthernet0/1
no sh
ip vrf forwarding UITS
ip address 18.0.0.1 255.255.255.0
exit
router ospf 1000 vrf UITS
network 18.0.0.0 0.0.0.255 area 1
exit
- PE3 :
ip vrf UITS
rd 1:1
route-target both 1:1
exit
interface GigabitEthernet0/1
no sh
ip vrf forwarding UITS
ip address 19.0.0.1 255.255.255.0
exit
router ospf 1000 vrf UITS
network 19.0.0.0 0.0.0.255 area 1
exit
· RD & RT :
- RD = Route Distniguisher = VPN Route Distniguisher = Keep all
the prefixes of the BGP Table
- RT = Route Target = Transfer the routes between VRF and VPN
· Test :
#do show run interface
gigabitEthernet 0/1
· CE Configuration :
- Hostname
- Addressing
- Routing : OSPF 1000 area 1
· Redistribution between OSPF 1000
and BGP 1 :
- PE1 & PE2 & PE3 :
router bgp 1
address-family ipv4 vrf UITS
redistribute ospf 1000 vrf UITS
exit
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exit
router ospf 1000 vrf UITS
redistribute bgp 1 subnets
exit
do copy run start
· Test :
