14 - Private WANS with Ethernet and MPLS Flashcards
What are the 3 MEF Service Types?
- Ethernet Line Service or E Line * Ethernet LAN Service E-LAN * Ethernet Tree Service or E-Tree
What 2 common features do all Metro E services have?
- Ethernet is used to connect customer device to Svc Provider’s device * it is a Layer 2 WAN service directly connecting customer devices together
Does the Metro E service act like a LAN switch connecting customer’s devices together?
Yes
What is an Access Link in Metro E service?
The physical link between the customer and the SP
What does UNI stand for?
User Network Interface
What is a UNI?
It’s the Interface between the User (customer) and the Network (SP)
What is a better name for Metro E?
Carrier Ethernet since it is no longer limited to one city
What is E-Line service?
A single Ethernet Line connects two customer devices
What is E-LAN service?
Full Mesh
What is E-Tree service?
Hub & spoke, Partial Mesh, Point-to-Multipoint
What is the name of E-Line service over MPLS?
Virtual Private Wire Service
What is the name of E-LAN service over MPLS?
Virtual Private LAN Service
What is the concept that defines which User Devices can communicate with which?
EVC - Ethernet Virtual Connection
What is the EVC in the E-Line Service?
The two customer devices can see each other
What is the EVC in the E-LAN Service?
All devices can see each other. Uses a single subnet for all devices.
What is the EVC in the E-Tree Service?
Remote devices can only see the hub router. All communication has to go through the hub router.
How many subnets would an E-Line Service need?
One for each pair of devices connected. Ex. 3 E-Lines = 3 Subnets
For any of the Metro E services what does it mean when a customer device has sub-interfaces?
Dot1q Trunking is being used.
How many subnets would an E-LAN Service use?
1 subnet, all devices become routing protocol neighbors
How many subnets would an E-Tree Service use?
1 subnet, each remote site has neighbor relationship with the hub router only. Hub router has neighbor relationships with all remote routers.
What is a Bandwidth Profile?
A plan to limit bandwith to something LESS than the Ethernet NIC could potentially send by the SP using QOS Policing and Customer using QOS Shaping
What is an MPLS VPN?
A layer 3 WAN
In MPLS VPNs what is the CE?
Customer Edge device. Typically a router that sits at the Customer’s site on one end of the Access Link.
In MPLS VPNs what is the PE?
Provider Edge device. It sits at the Edge of the Provider’s network on the other end of the Access Link.
What kind of Access Links can be used for an MPLS VPN?
A variety of Access Links
How does QOS work in an MPLS VPN?
Customer marks voice packets in Layer 3 header, SP recognizes the marking and honors them throughout the network.
Does an MPLS VPN provider need to know about the Customer’s routes?
Yes
In an MPLS VPN who does the CE become routing protocol neighbors with?
With the PE router on the other end of the Access Link
In an MPLS VPN does a CE router become routing protocol neighbors with other CE routers?
No.
In an MPLS VPN how does a CE router find out about routes on other CE routers?
The PE router performs Route Redistribution
In an MPLS VPN what routing protocol do PE routers run?
The customer’s routing protocol on the interface coming in from the CE and then Redistributing into Multiprotocol BGP throughout the SP Network.
What is a Super Backbone?
In an MPLS VPN if the Customer is running OSPF the PE routers combine to form and may extend an existing Area 0. CE routers may or may not be in Area 0.
In an MPLS VPN when the customer is running EIGRP how can the customer preserve accurate metrics when routes get redistributed into and out of the MPLS VPN?
By using the same EIGRP ASN number on all CE routers
