14 - Private WANS with Ethernet and MPLS

Question 1

What are the 3 MEF Service Types?

Answer 1

• Ethernet Line Service or E Line * Ethernet LAN Service E-LAN * Ethernet Tree Service or E-Tree

Question 2

What 2 common features do all Metro E services have?

Answer 2

• Ethernet is used to connect customer device to Svc Provider’s device * it is a Layer 2 WAN service directly connecting customer devices together

Question 3

Does the Metro E service act like a LAN switch connecting customer’s devices together?

Answer 3

Yes

Question 4

What is an Access Link in Metro E service?

Answer 4

The physical link between the customer and the SP

Question 5

What does UNI stand for?

Answer 5

User Network Interface

Question 6

What is a UNI?

Answer 6

It’s the Interface between the User (customer) and the Network (SP)

Question 7

What is a better name for Metro E?

Answer 7

Carrier Ethernet since it is no longer limited to one city

Question 8

What is E-Line service?

Answer 8

A single Ethernet Line connects two customer devices

Question 9

What is E-LAN service?

Answer 9

Full Mesh

Question 10

What is E-Tree service?

Answer 10

Hub & spoke, Partial Mesh, Point-to-Multipoint

Question 11

What is the name of E-Line service over MPLS?

Answer 11

Virtual Private Wire Service

Question 12

What is the name of E-LAN service over MPLS?

Answer 12

Virtual Private LAN Service

Question 13

What is the concept that defines which User Devices can communicate with which?

Answer 13

EVC - Ethernet Virtual Connection

Question 14

What is the EVC in the E-Line Service?

Answer 14

The two customer devices can see each other

Question 15

What is the EVC in the E-LAN Service?

Answer 15

All devices can see each other. Uses a single subnet for all devices.

Question 16

What is the EVC in the E-Tree Service?

Answer 16

Remote devices can only see the hub router. All communication has to go through the hub router.

Question 17

How many subnets would an E-Line Service need?

Answer 17

One for each pair of devices connected. Ex. 3 E-Lines = 3 Subnets

Question 18

For any of the Metro E services what does it mean when a customer device has sub-interfaces?

Answer 18

Dot1q Trunking is being used.

Question 19

How many subnets would an E-LAN Service use?

Answer 19

1 subnet, all devices become routing protocol neighbors

Question 20

How many subnets would an E-Tree Service use?

Answer 20

1 subnet, each remote site has neighbor relationship with the hub router only. Hub router has neighbor relationships with all remote routers.

Question 21

What is a Bandwidth Profile?

Answer 21

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

Question 22

What is an MPLS VPN?

Answer 22

A layer 3 WAN

Question 23

In MPLS VPNs what is the CE?

Answer 23

Customer Edge device. Typically a router that sits at the Customer’s site on one end of the Access Link.

Question 24

In MPLS VPNs what is the PE?

Answer 24

Provider Edge device. It sits at the Edge of the Provider’s network on the other end of the Access Link.

Question 25

What kind of Access Links can be used for an MPLS VPN?

Answer 25

A variety of Access Links

Question 26

How does QOS work in an MPLS VPN?

Answer 26

Customer marks voice packets in Layer 3 header, SP recognizes the marking and honors them throughout the network.

Question 27

Does an MPLS VPN provider need to know about the Customer's routes?

Answer 27

Yes

Question 28

In an MPLS VPN who does the CE become routing protocol neighbors with?

Answer 28

With the PE router on the other end of the Access Link

Question 29

In an MPLS VPN does a CE router become routing protocol neighbors with other CE routers?

Answer 29

No.

Question 30

In an MPLS VPN how does a CE router find out about routes on other CE routers?

Answer 30

The PE router performs Route Redistribution

Question 31

In an MPLS VPN what routing protocol do PE routers run?

Answer 31

The customer's routing protocol on the interface coming in from the CE and then Redistributing into Multiprotocol BGP throughout the SP Network.

Question 32

What is a Super Backbone?

Answer 32

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.

Question 33

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?

Answer 33

By using the same EIGRP ASN number on all CE routers