mpls l2 vpn Flashcards
What are the 3 types of L2 VPN models?
Local Switching, VPWS and VPLS
VPWS type that can be implemented over IP backbone
L2TPv3
What are the 3 elements of L2VPN architecture
Attachment Circuit - It is the circuit or element that is mapped into the PW • Ethernet port or VLAN • Frame-Relay port or just a DLCI • PPP port • ATM Virtual Path Identifier – VPI or Virtual Channel Identifier – VCI o Pseudowires P2P connection over the packet network Emulates operation of a “Transparent Cable” o Transport Technologies MPLS packet network (supports P2P and PMP) IP packet network (supports only P2P)
What are the transport technology options for circuits
Transport technology: MPLS or IP
Do VPWS circuits learn MACs
False, VPLS does
________ _________ ________ is the ability to process and classify multiple Ethernet frames and their attributes
Flexible ethernet mapping
______ _______ is the MAC learning domain regardless of which VLANs are mapped to it
The Bridge Domain
An _______ _______ is a Layer 2 logical subinterface used to classify traffic under a physical or a bundle interface. A physical interface can be an Ethernet interface and has ports on the line card.
Ethernet Flow Point (EFP) Subinterface that is mapped to a PW
Some fields are not transmitted in the PW
True: • Encapsulates frame without transmission fields that offer no benefit, such as synchronization data preamble Start Frame Delimiter – SFD Marks the beginning of the frame FCS
In IOS XR an ACL is required for BPDUS filters, this is necessary to prevent the port from entering err-disable for receiving BPDUs from inconsistent VLANs
True
Does VPWS emulate a LAN using PW or VCs
False, VPLS does
In VPLS an unknown unicast, multicast and broadcast frame is propagated to all PEs in a common VPLS, upon reaching these PEs the frame is forwarded to all client ports but NOT forwarded to ANY OTHER PE
True. Split horizon • VPLS Split horizon is similar to iBGP mesh
Is VPLS composed of N individual PWs
True
Does H-VPLS operate independently of Split Horizon
False, split horizon must be disabled.
_________ __________ _______ • The Virtual Switching Instance, implemented as VFI is a virtual L2 entity that defines the VPLS domain • VFI functions o Connects ACs to PWs
Virtual Forwarding Instance
Is a _ _ _ used to connect a VPLS to a bridge domain to create a routed VPLS
True
Are MAC learning and aging processes handled by IGP extensions
False, it is the responsibility of LDP extensions
Can BGP and LDP be used for discovery
False, only BGP
In BGP configuration are RD and RT used the same way as in L3VPN
True
Is the VPLS Edge Identifier - VE ID announced by BGP
True
What are the 3 steps of VPLS configuration
Service instance configuration on the interface Configuration of the l2vpn vrf context NAME – manually add peers Configuration of the bridge domain – add the interface in its service instance – add the VFI Name
In H-VPLS is the N-PE like a Route Reflector in BGP
True, basically U-PEs will establish PWs only with N-PE
ELAN = H-VPLS and ETREE = VPLS
False, the reverse
Should split Horizon be disabled on U-PE > N-PE uplinks and enabled on N-PE > N-PE uplinks
True
What is the framework created to unify and standardize Ethernet service configurations called
Ethernet Virtual Circuit
What is the purpose of the EVC framework
facilitate the abstraction of a physical interface through the multiplexing of services
In EVC what is the name of the abstraction entity where interesting traffic is associated with the service
Ethernet Flow Point
What is the difference between EFP, BVI and BD
Ethernet Flow Point (EFP) Abstraction of an Ethernet service on an interface. ‘service instance instance_number ethernet’ under the interface this ‘binds’ an EFP to an interface. Bridge Domain (BD) Ethernet Broadcast domain. A single VLAN can have multiple BDs. Bridge Domain Interface (BDI) Layer 3 interface associated with a BD to perform Integrated Routing and Bridging (IRB). Gateway between a Layer 2 domain within a Bridge Domain and the Layer 3 domain, similar to an SVI.
Can COS or ethertype be used to match traffic to an EFP
Yes
Does BVI allow VLAN significance by port
False, it is BD, bridge domain
The ___ can be used to provide an “exit point” out of the Bridge Domain and into a routed segment, and uses the standard ARP mechanism to resolve addresses.
BDI
What are the 3 operations of Advanced Frame Manipulation or VLAN Acrobatics
Push, pop and translate
What is the effect of the command below: rewrite ingress tag translate 1to1 dot1q 20 symmetric
translates the outer tag to 20, regardless of what it is
