Tagged with " MPLS"

MPLS VRF Configuration

VRF Configuration tasks;

  • Create a VRF table
  • Assign RD to the VRF
  • Specify export and import route targets
  • (optional) Configure a VPN ID
  • Assign interfaces to VRFs

Commands;

  • (config)# ip vrf <name>
  • (config-vrf)# rd route-distinguisher – can be 16 bit AS number: 32 bit decimal no OR 32 bit IP:16 bit decimal
  • router(config-vrf)# route-target export RT
  • (config-vrf)# route-target import RT
  • (config-vrf)# route-target both RT

VPN ID config;

  • (config)# ip vrf vrf-name
  • (config-if)# vpn id oui:vpn-index
  • (config-if)# ip vrf forwarding vrf-name #! then resign the IP address

MPLS Configuration

Mandatory

  • Enable CEF switching
  • Configure LDP on every label-enabled interface

Optional

  • Configure MPLS ID
  • Configure MTU size for labelled packets
  • Configure IP TTL propagation
  • Configure conditional label advertising

mpls ldp router-id interface [force]

router(config-if)# mpls ip

router(config-if)#mpls label protocol [tdp|ldp|both]   #!IOS v12.4(3) the default is now ldp – tdp was previously

router(config-if)#mpls mtu bytes

router(config)#mpls ip propagate-ttl [forwarded | local] #\ default is enabled

router(config)#mpls ldp advertise-labels [for <prefix-acl> [to <peer-acl>]]

#sh mpls ldp parameters

#show mpls interfaces

#show mpls ldp discovery

#sh mpls ldp neighbor

#sh mpls ldp neighbor detail

#sho mpls ldp bindings

#show mpls forwarding-table

#sh ip cef detail

debug mpls ldp ….

debug mpls lfib ….

debug mpls packets [interface]

MPLS (Multi-Protocol Label Switching)

OK, so having known about MPLS for a few years and actually get a provided service in my work environment as well as the fact it is on the CCIE R&S blueprint I thought I should get a much better understanding of how it works and the various terminology’s. My notes so far;

The benifits of MPLS;

  • The use of one unified network infrastructure
  • Better IP over ATM integration
  • Border Gateway Protocol (BGP)-free core
  • The peer-to-peer model for MPLS VPN
  • Optimal traffic flow
  • Traffic engineering
Some MPLS applications;
  • Traffic engineering (MPLS TE)
  • MPLS VPN
  • AToM (Any Transport over MPLS)
  • VPLS
  • Unicast IP Routing
  • Multicast IP routing
  • QoS
What are the advantages of the MPLS VPN solution for the service provider over all the other
VPN solutions?
  • MPLS VPN allows for easy provisioning of sites and allows for optimal traffic flow in the backbone network at all times.
Four technologies that can be used to carry IP over ATM are as follows:
  • RFC 1483
  • LANE
  • MPOA
  • MPLS
Two pre-MPLS protocols that use label switching.
  • ATM
  • Frame Relay
The ATM switches need an IP routing protocol and a label distribution protocol to operate MPLS.
To ensure optimal traffic flow between all the customer sites in an ATM or Frame Relay overlay network the connectivity between the customer sites needs to be a full mesh of virtual circuits.
=—-
FEC = Forwarding Equlivalance Class
MPLS VPNs are highly scaleable and support  IP Services such as;
  • Multicast
  • Quality of QoS
  • Telephany support within a VPN
  • Centrilised services including content and web hosting VPN

AToM transports Layer-2  traffic over an IP or MPLS backbone

AT0M - accommodates many Layer-2 frames including Ethernet, Frame Relay, ATM, PPP and HDLC

Examples of AToM;

  • Ethernet over MPLS (EoMPS) – Applications include TLS and VPLS
  • ATM over MPLS – supports 2 types of transport mechanisms of ATM frames across an MPLS core: AAL5-over-MPLS & Cell-relay modes.
  • Frame Relay over MPLS