Module 2 MEF Services and Attributes

Which three statements apply to Access-EPL and Access-EVPL services?

Access-EPL maps all CE-VLANs to one OVC The OVC has one UNI and one ENNI end point Access-EVPL can share a UNI with other ethernet access services.

Consider the following diagram. What service attribute enables CE VLANs to be translated across the EVC

CE-VLAN ID Preservation

A subscriber needs to purchase a single ethernet service that will allow several branch offices access to critical business applications. Each application uses a different VLAN, but all other VLANS should be bloced by the service. Which two service attributes and settings are required to implement this scenario

CE-VLAN ID preservation = Yes Bundling = Yes

For EPL service between UNI A and UNI B, what is the correct delivery behavior for for an ingress service frame at UNI A without a C-Tag

Deliver the frame to UNI B unchanged.

Which three actions are valid for data service frame disposition?

Discard Deliver Conditionally Deliver Unconditionally

What is the allowed service frame format at the UNI

The frame format at the UNI must be according to the IEEE 802.3 -2012 Standard

An EVC has a MFS set to 1522 Bytes. A frame of size 1526 bytes arrives at the ingress UNI. What behavior is likely to happen according to MEF 10.3?

The frame should be dropped.

What are the two properties of EPL that make it a good service for an enterprise that needs to connect two locations and extend the corporate VLANs across both locations?

There is no need for the enterprise and the service provider to coordinate VLAN identifier values. The enterprise can run STP across the two locations if desired

What is the role of an ENNI

To exchange ethernet frames for one or more services between two network operators.

A UNI is configured with Service Multiplexing disabled and Bundling enabled. Which is true?

Traffic may be passed or blocked based on CE-VLAN ID

Which three statements apply to transit E-Line and Transit E-LAN services

Transit E-Line OVC has two ENNIs Transit E-LAN OVC has three or more ENNIs Requires that CE-VLAN ID and CE-VLAN CoS preservation be enabled

Condider the diagram. An ingress frame arrives at UNI 1 with the CE-VLAN ID = 37. What UNI will it egress and what will be the CE VLAN ID of the frame as it egresses the UNI?

UNI 4 with CE VLAN = 33

Which attributes are UNI attributes

UNI MFS Number of links

A UNI is configured with both bundlin and all to one bundling disabled. How many CE-VLAN ID's can be mapped to a given EVC at this UNI?

1

Which value is the lowest bound for ENNI MFS?

1526 bytes

An ENNI supports multiple EVCs including some that are configured to handle an EVC Maximum frame size as large as 1800 bytes. What is the smallest value that should be assigned the ENNI MFS that will support these EVCs

1804 (allowing for the addition of an S-Tag adding the 4 bytes)

An EVPL service is put into place across four operator networks as show. How many UNIs, ENNIs, OVCs and EVCs must be provisioned?

2 UNIs, 3 ENNIs, 4 OVCs and 1 EVC

Consider the diagram. What is the total number of ENNIs that Alpha Service Provider needs to assign and coordinate with the four CEN operators.

3

What is the total number of OVC end points at UNIs in CEN C

3. Remember - count the UNI end points, do not add the ENNI endpoints.

A subscriber has an EVP-Tree service with a UNI list containing 5 UNIs. Two are designated as a Root Unis; three are designated as Leaf UNIs. If a service frame ingresses the CEN at one of the Root UNIs, what is the maximum number of service frames that can result?

4

A UNI is configured with Service Multiplexing enabled, bundling disabled, and all to one bundling disabled. What is the maximum number of EVCs that can be terminated on this UNI?

4094

What are the total number of OVCs that an Alpha Service Provider needs to assign and coordinate with the four CEN Operators.

5 - Count the different OVC Connections/end points per CEN

What is an ENNI from the perspective of MEF

A reference point representing the boundary between two operator carrier ethernet networks that are operated as seperate administrative domains.

Angel Cupcakes, a business enterprise with numerous independently owned bakery store fronts, wants to connect each bakery to the internet to allow customers to place orders via a web-based application. which of the following service options is the most suitable?

A single EP-Tree

EVC per UNI attributes apply to a specific EVC with respect to a specific UNI. How is the UNI EVC ID formed?

A string formed by a concatenation of the UNI ID and EVC ID

Which configurations apply to an ethernet private tree?

All UNIs must have service multiplexing disabled All UNIs must have bundling disabled All UNIs must have All to ONe bundling enabled.

A UNI has the all to one bundling attribute enabled. what is true

All service frames at the UNI are mapped to a single EVC

Which one of the following is a requirement of an OVC?

An ENNI

What characteristic distinguishes an O-LAN service from O-Line and O-Tree services

An O-LAN is a multipoint to multipoint OVC

What characteristic distinguishes an O-Tree service from O-Line and O-LAN services

An O-Tree has leaf OVC end points

What is an Operator Virtual Connection

An association of OVC end points at External Interfaces within the same Carrier Ethernet network.

What is an ethernet virtual connection EVC?

An association of two or more UNIs that limits the exchange of service frames to UNIs in the EVC

Where are Trunk OVC end points applied in a multi-CE topologys to support E-Tree services?

At the ENNI

According to the MEF Glossary, equipment that connects to the UNI and is commonly owned by enterprise subscribers is called the

Customer Edge

What three service types are defined in MEF 6.2

ELAN, ELINE, ETREE

Which sercie types require that CE-VLAN preservation be enabled

EP-Tree EP-LAN EPL

Which two services are allowed to tunnel (pass) a service frame with destination MAC address 01-80-C2-00-00-00 that contains a spanning tree protocol message?

EPL EP-LAN

Which two services are compatible with extending the STP across enterprise locations connected by the service.

EPLAN EP-Tree

Which Ethernet service combinations can be offered simultaneously at a given UNI?

EVP-LAN and EVPL; EVPL and EVP-Tree; EVP-Tree and EVP-LAN

An enterprise has three sites named A, B, and C. Each site has a single UNI. The three sites need to be connected together and a firewall at the A site needs to be connected to an ISP. Which service arrangment will satisfy the stated requirements?

EVP-LAN connecting the enterprise sites and the EvPL connecting site A to the ISP

Which configurations apply to an ethernet virtual private LAN?

EVP-LAN service create a multipoint to multipoint EVC and have the following characteristics: VLAN Based All UNIs are Roots Requires All to One Bundling disabled, Bundling can be enabled or disabled, service multiplexing can be enabled or disabled. Allows multiple services to share a single UNI.

A service provider needs to proivde access to five enterprises via a primary data center location and a backup data center location. Each data center location has a single UNI. The two data center locations are connected by an EVPL to allow data mirroring. Which service arrangement provides the connectivity between each enterprise and both data centers while preventing the enterprises from seeing each other's traffic?

EVP-Tree

Bigfoot ISP has a 1 GbpsUNI to be shared among 50 customers, each needing 5 Mbps access bandwidth to the internet. None of the customer may see traffic from other customers. Which three service arrangements meet the stated requirments.

Ethernet Virtual Private Tree EP-Tree One EVPL between each customer and ISP

An ENNI frame is mapped to an OVC end point. Which ENNI frame format is not in scope with MEF 26.2 ENNI and Operator service attributes?

Ethernet service frame with multiple S-tags and One C-tag (common but vendor specific and not part of the MEF policy)

What does the End Point map at an ENNI specify?

How each ENNI frame with an S-tag is associated with an OVC end point within an operator CEN

According to the MEF glossary, what is a UNI?

It is the physical demarcation point between the responsibility of the subscriber and the responsibility of the service provider

A customer uses an EVP-LAN. The customer needs to avoid sending broadcast frames across the ENN that connects some of the UNs. which attribute should be used to block broadcasts over the ENNI

OVC Service attribute for broadcast service frame delivery.

An enterprise has a hub office location and three branch locations that need to be connected to the hub. The equipment at each branch consists of a single router port with an Ethernet interface that is unable to support VLANs. At the hub location there is a router that supports VLANS and has a single available port. Which of the following is a solution you can offer the potential subscriber?

One EVPL between each branch and the hub

In the MEF 26 Service model, what organization is responsible for delivering Ethernet frames between an ENNI and other ENNIs and/or UNIs?

Operator

Which two protection mechanisms are allowed at an ENNI that contains Multiple Links

Other Link Aggregation with LACP

Which three actions are valid for ingress L2CP frames at an External Interface EI?

Peer with a protocol entity at the EI Pass to the EVC/OVC Discard

Consider the OVC End Point Map, identify the statement that describes the behavior of frames handled by this map

The end point map bundles service frames with S-Tags 158 and 166 onto one OVC (the end point indentifier shows the same for both S-Tag 158 and 166)

Which kind of UNI to UNI connectivity is used for an EP-Tree service?

Rooted Multipoint Ethernet Virtual Connection

An enterprise subscriber needs to connect four sites with a single UNI and two EVCs at each site, to share multiple VLANs between sites and to have internet access for each site. What are the expected parameters for the service multiplexing and bundling attributes for the UNI at each site?

Service Multiplexing equals Enabled; Bundling equals Enabled

Identify the action that takes place when a frame with S-Tag 2023 Ingresses into CEN B at the ENN aandhhas MA destination address located at UNI Ab

The S-Tag 2023 is removed, S-Tag 1028 is applied, and the frame is forwarded to OVC end point B2. (Haripin Switching)

Which statement describes UNI resiliency, as defined by MEF 10.3

When UNI resiliency is mandatory, it must be according to LAG

What are the two properties of EPL that make it a good service for an enterprise that needs to connect two locations and extend the corporate VLANs across both locations

there is no need for the enterprise and the service provider to coordinate VLAN identifier values The enterprise can run STP across the two locations if desired.

Why was the minimum MFS for ENNI frame expanded beyond the minimum MFS of a UNI frame

to account for a single S-tag