MEF Carrier Ethernet 2.0 - Exam Prep
UNI Service Frame Format is what?
IEEE 802.3
Any time you have preserve CE-LAN IDs you are preserving CoS
True
S-OAM standards are based on what?
• IEEE 802.1ag Connectivity and Fault Management • ITU-T Y.1731 CFM and Performance monitoring
Benefits of Bridging
• extend reach of Ethernet. • Reduce # of stations
When the OVC EP Map has Bundling, the OVC Must have ENNI on both ends. Hairpin is prohibited. What else is critical?
1) CE-VLAN ID Preservation= Yes 2) CE-VLAN CoS Preservation =Yes 3) S-VLAN ID Preservation= Yes
UNI 2.1 Added
1) Egress Bandwidth Profile 2) MFS 3) Service OAM
The IWF is responsible for what? (CESoETH)
1) Frame Encapsulation 2) Synchronization 3) Defect Identification
For EPL UNI Bandwidth Profile Assignments are not allowed where?
1) Ingress BWP is not allowed Per UNI 2) Egress BWP is not allowed per UNI
UNI 2.2 Added
1) LINK Protection 2) Protection using LAG 3) Link OAM
Describe the OVC Types
1) Point to Point (OVC associates exactly two root OVC End Points) 2) Multi Point to Multipoint OVC can associate two or more root OVCs End Points 3) Rooted Multipoint OVC Can associated at least on leaf or trunk OVC End Point
An E-Access Service is point to point OVC which is used to extend Ethernet services to one remove off-net UNI. What are the four constraints?
1) Supports Single CoS only (BWP is only Class of service for E-Access) 2) Ingress bandwidth profiles per OVC EP only (no egress) 3) Extend E-LINE or E-LAN services types only - NOT E-Tree 4) C-Tag VLAN and CoS Preservation is ALWAYS enabled
What are the four ENNI performance tiers?
1. Metro 2. Regional 3. Continental 4. Global The further out you go the higher the measurements (Time)
Ethernet Service is the Concatenation of what?
1. Service Type (e.g. EPL, E-LAN) 2. Service Attributes ( Bundled, All to one, etc. 3. Parameters (segregation, CoS)
What are the three types of Technical Docs produced by MEF?
1. Technical Specification 2. Implementation Agreements 3. Abstract Test Suites
What are EVC Service Attributes?
1. UNI Service Attributes a. Physical and Port Specs b. Mapping of CE VLANs 2. EVC Per Uni Service Attributes a. Ingres and egress BWP b. Differ for eline, elan and etree c. Service type dependent 3. EVC Service Attributes a. Unicast / Broadcast delivery b. L2CP Processing Options c. EVC Performance
Operator Service Attributes include?
1. UNI and ENNI Service Attributes (e.g Frame formats, end point (ep) maps) 2. OCV EP per UNI and ENNI Service Attributes (Cos IDs, Ingres/egress BWPs) 3. OVC Service Attributes (Unicast, Multicast, Broacast delivery, CE-VLAN CoS Preserviation, SLS specs)
CCMs are set at what for Protection Switching?
1/300 for Protection switching
CCMs are set at what interval for Fault Monitoring?
1/Sec for Fault Monitoring
CCMs are set at what for Performance Monitoring?
10/Sec for Performance Monitoring
What is the frame size for ENNI
1526 (double tagged with C and S tag)
8 Maintenance Default Levels
6. Subscriber MEG 5. Test MEG 4. EVC MEG 3. Service Provider MEG 2. Operator MEG 1. UNI MEG 1. ENIN MEG
What is the standard for Provider Bridging
802.1Q
Service Activation Criteria is defined as
A Conformance test to verify of a subset of the SLS
Performance metrics always apply to what?
A qualified service frame of a given subset of ordered UNI pairs (UNI A to UNI Z) always for a specific Class of Service (CoS).
For One Way Frame Loss
Always be the maximum frame loss for the entire EVC
Service Creation Always Happens where?
At the UNI
S-Tag preservation only occurs where?
Between ENNIs when performing endpoint bundling on an E-Transit line
CoS for ENNI are marked by what? How many classes of Service are there defined by MEF?
CoS is marked by S-Tag PCP Value 3 CoS (High, Medium, Low)- however only the lowest class for CoS is CIR and EIR greater than or equal to 0
Loss of 3 CCMs = what?
Continuity/Connectivity Failure
CE 2.0 Added what over CE 1.0
E- Tree E-Access Multi-CoS Interconnect
What are the different Service Types?
E-line E-LAN E-TREE
How many VLAN Tags can an EVC carry?
Each EVC can carry 4096 VLAN tags
In order to verify EVC connectivity or isolate a fault in the network, which S-OAM FM tool could be used?
Ethernet loopback session with the remote MEP
What is the difference between how a equipment provider gets MEF Certified vs. how a Service Provider gets Certified?
For Equipment provider, Testing takes place in lab. For Service Provider, Testing takes place in production network.
Performance management DMM/DMR messages are used for which of the following?
Frame Delay
Bandwidth Profile Algorithm is a Function of what?
Frame Length and Arrival Time
Which EVC Performance Metric is used for Characterizing short term disruption in Carrier Ethernet services based on Frame loss?
High Loss Interval (HLI)
MEF 48 (Service Activation Testing) is based on what?
ITU-T Y 1564 Ethernet Service Activation Measurement
Connectivity Fault Monitoring (CFM) and Performance Monitoring was derived from what?
ITU-T Y.1731 OAM functions and mechanisms for Ethernet based networks
DEI=0 refers to what?
It can not drop (Not drop Eligible)
What are the benefits of Hairpin switching
Keeps traffic local and extends a LAN
An OVC End Point at the UNI can have the role of Leaf or a Root. An OVC End Point at the ENNI can have the role of what?
Leaf, Root or a Trunk
Three EVCs Share Total Bandwidth Available at the UNI. The sum of the Configured CIRs must be what?
Less than or equal to the speed of the UNI. However the sum of the EIRs may exceed the speed of the UNI which will result in yellow traffic being dropped if oversubcribed.
When ENNI Consists of 2 links what type of protection is required?
Link Aggregation (Active and Protect) 802.1
What is the MEF Spec for OVC? What is the MEF Spec for Service Activation Testing?
MEF 51 MEF 48
On the EVC, you have to have at least CoS enabled to perform what?
Metrics and measurements.
Token Sharing bandwidth profile allows for what?
Multiple flows within the same envelope. Note: The collection bandwidth profiles within an EVC is considered an 'envelope'.
What are standard OVC Service Attributes for Standard CoS and Color Identifiers?
OVC EP or non-overlapping sets of S-Tag PCP with or without DEI
What are the lowest MEG levels available for the Service Provider or SOAM Operator?
Operator MUST suport value of 4 or less Operator SHOULD support a value of 2 or less OVC available MEG level MUST be less than or equal to 6
Mandatory Performance Testing is?
PM-1 Point to Multipoint. - Single-ended delay - Single-ended synthetic loss
Any time you see STP
Port- private based service
All to One Bundling is always what?
Private Service (EPL, EP-LAN)
L2CP can only pass on what?
Private Services
What is the minimum number of class of services for Mobile Backhaul?
SOAM enabled on at least 2 classes of service
CE VLAN ID and COS Preservation depends on the EVC requirement. What is the requirement if the EVC has Bundling (Including All to One)?
The OVC MUST PRESERVE the VLAN-ID!!!
How many types of Bandwidth Profiles are there?
Three 1. BWP At the UNI 2. BWP at EVC 3. BWP per CoS at Ingress
At the ENNI each S-Tagged ENNI Fram Maps to a single OVC EP and therefore to a single OVC. True or False
True
At the UNI each Service Frame Maps to a single OVC End Point (EP) and therefore to a single OVC. True or False
True
BWP can only be configured on OVC for CoS
True
OVC end Point Map Bundling is only done ENNI to ENNI (E-Transit). True or False
True
When SOAM is used across a chain of OVCs, the OVC with the greatest OVC available MEG value will determine the lowest MEG level that could be used by the Service Provider or Super Operator?
True
CE-VLAN ID Preservation must be enabled when Bundling
True (need to preserve CE-VLAN ID and CoS for EVPL, EVP-LAN and EVP-TREE)
UNI Protection using Link Aggregation Control Protocol (LACP) is Mandatory for what?
UNI Type 2.2
Describe E-Access
UNI to ENNI
How should EPL and Access EIP service deliver multicast, broadcast and unicast frames?
Unconditionally
CESoETH must deliver multicast frames how?
Unconditionally.
CE-VLAN Preservation Can be set to Disabled
When CE-VLANs are set to one to one mapping
What is Bandwidth Profile Formula?
X= (CIR /8 * Time) + CBS
