What is Inter as MPLS?

–> We use Inter AS MPLS VPN in this scenario when there are two service providers involved to provide MPLS connectivity between different customer sites. –> Customer Sites need to be connected to different Service Providers.

What is MPLS Option B?

The second method is known as inter-AS option B or 2547bis option B, after IETF RFC 4364—BGP/MPLS IP Virtual Private Networks (VPNs) (February 2006). This method uses BGP to signal VPN labels between the AS boundary routers (Figure 1). The base MPLS tunnels are local to each AS.

What is option A in BGP?

Inter-AS Option A uses back to back vrf connections between the ASBR routers. It provides one of the solutions for running MPLS over two BGP ASes. This might be required if two carrier merge, or if one customer is connected to two carriers and would like to maintain end to end MLPS VPN.

What are the types of MPLS?

There are three primary types of MPLS VPNs: Layer 2 VPNs, Layer 2 circuits, and Layer 3 VPNs. All types of MPLS VPNs share certain components: The provider edge (PE) routers in the provider’s network connect to the customer edge (CE) routers located at customer sites.

What is bgp option C?

Option C introduces multihop EBGP redistribution of labeled VPN-IPv4 routes between source and destination autonomous systems. Labeled IPv4 routes are redistributed by EBGP between neighboring autonomous systems. Inter-AS option C uses BGP as the label distribution protocol.

What is mpls bgp forwarding?

In case of Inter-AS Option B, BGP is used as label distribution protocol between ASBRs. So the command “mpls bgp forwarding” enables ASBR to send/accept labeled packet over the configured interface (whcih is towards the other ASBR).

Why use MP BGP?

Multiprotocol BGP (MP-BGP) is an extension to BGP that enables BGP to carry routing information for multiple network layers and address families. MP-BGP can carry the unicast routes used for multicast routing separately from the routes used for unicast IP forwarding.

What is inter autonomous system?

An Autonomous System (AS) is a collection of routers whose prefixes and routing policies are under common administrative control. Routing between Autonomous Systems (inter-AS routing) is external to the AS and allows one AS to send traffic to another AS.

What are the main differences between intra AS and Inter as routing?

Intradomain routing protocols ignores the internet outside the AS(autonomous system). Interdomain routing protocol assumes that the internet contains the collection of interconnected AS(autonomous systems).