1. … what buyers need to understand … what providers need to communicate
Metro Ethernet Services
… what buyers need to understand … what providers need to communicate
About the author:
Ralph Santitoro has taken a leadership role in defining Ethernet services in the Metro Ethernet Forum’s (MEF) Technical Committee and has actively participated in the MEF since December Mr. Santitoro is also editor of the MEF’s Ethernet Services Definitions, Traffic Management and QoS Framework technical specifications and co-chairs the MEF’s Technical Marketing and Web Presence Committee.
Ralph Santitoro
Co-chair, MEF Technical Marketing Committee

2. Metro Ethernet Services Overview v1.2
Contents
Ethernet as a Service
Ethernet Service Benefits
MEF Phase I Service Documents
Defining an Ethernet Service
Example E-Line and E-LAN Services
Ethernet SLAs
Ethernet Service Summary
References and Resources
Metro Ethernet Services Overview v1.2

3. Ethernet as a Service Ethernet’s origins in the Enterprise
Used as a LAN connectivity technology
Just plug it in and start using it
Ethernet’s new usage as a Service
Requires “service attributes” like other MAN / WAN services
Ethernet UNI, Ethernet “VC”, Service Performance, etc.
Same Ethernet technology just used in a new way
Metro Ethernet Services Overview v1.2

4. Ethernet Service Benefits
Ease of use
Widely available, well understood technology
Simplifies network operations (OAM&P)
Cost Effectiveness
Widespread use of Ethernet interface
Purchase bandwidth only when needed
Flexibility
Single UNI can connect to multiple services
Internet, VPN, Extranet supplier, Storage Provider
Bandwidth can be added in 1Mbps increments
Metro Ethernet Services Overview v1.2

5. Let’s look at TDM and other L2 Services
TDM hierarchy or L2 Service dictates bandwidth increments and technology
Inflexible Bandwidth Scalability
Increasing non-Ethernet service bandwidth often requires:
New service (step function)
T1T3, FRATM
New hardware
new interface or equipment
New service provisioning
different protocols / technologies
Often resulting in:
Oversubscribing to meet growing bandwidth needs
OC-48
OC-12
OC-3 T3 T1
POS
ATM
Frame Relay
1.5M M M M G
Metro Ethernet Services Overview v1.2

6. Ethernet Service Benefits over TDM/other L2 Services
Ethernet provides flexible bandwidth increments using same technology
Flexible Bandwidth Scalability
Increasing Ethernet service bandwidth:
Requires just bandwidth provisioning
Provision only amount of BW needed
Same protocol for LAN and MAN
Lower OpEx & CapEx with Ethernet
25-40% lower cost than
TDM, Frame Relay, ATM interfaces1
10x lower cost
than high speed SONET interfaces1
Easier and less costly to meet growing bandwidth needs
OC-48
OC-12
OC-3 T3 T1
1GbE
10/100MbE
POS
ATM
Ethernet
Frame Relay
1.5M M M M G
1 Source: Network Strategy Partners, LLC
Metro Ethernet Services Overview v1.2

7. MEF Phase I Service Documents
Phase I consists of 3 technical specifications
Ethernet Services Model (ESM - MEF 1.0 standard)
Defines Ethernet service building blocks (service attributes)
Defines a framework describing how to build an Ethernet service
does not define Ethernet services
Ethernet Services Definitions (ESD)
Defines how to apply the ESM building blocks to create services
Defines Ethernet Line (E-Line) and Ethernet LAN (E-LAN) service types and instances of them (EPL, EVPL, EIA, etc.)
Ethernet Traffic Management (ETM)
Defines traffic management and service performance requirements to create CoS-based SLAs
Metro Ethernet Services Overview v1.2

8. Relationship between MEF Phase I Service documents
Ethernet Service Definitions (ESD)
MEF Ethernet Service Model (ESM) (Ratified Sept. 2003)
Ethernet Traffic Management (ETM)
Metro Ethernet Services Overview v1.2

9. Ethernet Services Model (ESM)
Ratified by MEF Tech. Committee - Sept. 2003
into Technical Specification MEF 1.0
Defines building blocks for creating services
Building blocks consist of Ethernet Service Attributes and Parameters defined for:
Ethernet UNI (User Network Interface)
Ethernet Virtual Circuit (EVC)
MEF 1.0 defines the building blocks to create services
Metro Ethernet Services Overview v1.2

10. How the MEF defines an Ethernet Service
MEF 1.0 defines the Ethernet Service Definition Framework
A service is defined via
Service Type
Service Attributes
Service Attribute Parameters
Defined in ESD
Defined in ESM (MEF 1.0) and ETM
Defined in ESM (MEF 1.0) and ETM
Metro Ethernet Services Overview v1.2

11. Ethernet Service – Basic Model defined in MEF 1.0
Customer Equipment (CE) attaches to UNI
CE can be
router
IEEE 802.1Q bridge (switch)
UNI (User Network Interface)
Standard IEEE Ethernet PHY and MAC
10Mbps, 100Mbps, 1Gbps or 10Gbps
Metro Ethernet Network (MEN)
May use different transport and service delivery technologies
SONET/SDH, WDM, RPR, MAC-in-MAC, Q-in-Q, MPLS CE
UNI
Metro Ethernet Network (MEN) CE
UNI CE
Metro Ethernet Services Overview v1.2

12. Ethernet Service Type defined in ESD
Generic Ethernet connectivity service construct
Each Ethernet Service Type
has a set of Ethernet Service Attributes
MEF has defined 2 Ethernet Service Types
Ethernet Line (E-Line) Service
Provides Point-to-Point connectivity
Ethernet LAN (E-LAN) Service
Provides Multipoint-to-Multipoint (Any-to-Any) connectivity
Service Types are generic constructs used to create services
Metro Ethernet Services Overview v1.2

13. Ethernet Virtual Connection (EVC) defined in MEF 1.0
An EVC is “an instance of an association of 2 or more UNIs”
EVCs help visualize the Ethernet connections
Like Frame Relay and ATM PVCs
MEF has defined 2 EVC types
Point-to-Point
Multipoint-to-Multipoint
MEN
UNI
MEN
Point-to-Point EVC
Multipoint-to-Multipoint EVC
EVCs help conceptualize the service connectivity
Metro Ethernet Services Overview v1.2

14. Ethernet Service Attributes defined in MEF 1.0, ESD and ETM
the capabilities of the Ethernet Service Type
Service Attributes defined for UNI and EVC:
Physical Interface
Bandwidth Profiles
Service Performance
Service Frame Delivery
Service Multiplexing
Etc….
Service Attributes define the service characteristics
Metro Ethernet Services Overview v1.2

15. UNI and EVC Service Attribute Details
Service Attributes defined in
MEF 1.0 Technical Specification

16. EVC Service Attributes
Service Attribute Parameters
EVC Type
Point-to-Point or Multipoint-to-Multipoint
UNI List
A list of UNIs (identified via the UNI Identifier service attribute) used with the EVC
CE-VLAN ID Preservation
Yes or No. Specifies whether customer VLAN ID is preserved or not.
CE-VLAN CoS Preservation
Yes or No. Specifies whether customer VLAN CoS (802.1p) is preserved or not.
Unicast Service Frame Delivery
Specifies whether unicast frames are Discarded, Delivered Unconditionally or Delivered Conditionally
Multicast Service Frame Delivery
Specifies whether multicast frames are Discarded, Delivered Unconditionally or Delivered Conditionally
Broadcast Service Frame Delivery
Specifies whether broadcast frames are Discarded, Delivered Unconditionally or Delivered Conditionally
Layer 2 Control Protocol Processing
Discard or Tunnel per protocol
Service Performance
Specifies the Frame Delay, Frame Jitter and Frame Loss per EVC or frames within an EVC identified via their CE-VLAN CoS (802.1p) value
Metro Ethernet Services Overview v1.2

17. UNI Service Attributes
Service Attribute Parameters
UNI Identifier
A string used to identity of a UNI, e.g., NYCBldg12Rm102Slot22Port3
Physical Medium
Standard Ethernet PHY
Speed
10 Mbps, 100 Mbps, 1 Gbps or 10 Gbps
Mode
Full Duplex or Auto negotiation
MAC Layer
IEEE
Service Multiplexing
Yes or No. Defines whether multiple services can be on the UNI
UNI EVC ID
A string used identify an EVC, e.g., NYCBldg1Rm102Slot22Port3EVC3
CE-VLAN ID / EVC Map
Mapping table of customer VLAN IDs to EVC
Max. Number of EVCs
The maximum number of EVCs allowed per UNI
Bundling
No or Yes. Specifies that one or more customer VLAN IDs are mapped to an EVC at the UNI
All to One Bundling
No or Yes (all customer VLAN IDs are mapped to an EVC at the UNI).
Ingress Bandwidth Profile Per Ingress UNI
None or <CIR, CBS, EIR, EBS>. This Bandwidth profile applies to all frames across the UNI.
Ingress Bandwidth Profile Per EVC
None or <CIR, CBS, EIR, EBS>. This Bandwidth profile applies to all frames over particular EVC.
Ingress Bandwidth Profile Per CoS ID
None or <CIR, CBS, EIR, EBS>. This Bandwidth profile applies to all frames marked with a particular CoS ID over an EVC.
Layer 2 Control Protocol Processing
Discard, Peer or Pass to EVC per protocol
Metro Ethernet Services Overview v1.2

18. E-Line and E-LAN Service Types defined in ESD
Point-to-Point EVC
E-Line Service used to create
Private Line Services
Ethernet Internet Access
Point-to-Point VPNs
E-LAN Service used to create
Multipoint VPNs
Transparent LAN Service
UNI CE
MEN CE
UNI
E-Line Service type
Multipoint-to-Multipoint EVC
UNI
UNI CE CE
MEN CE
UNI
UNI CE
E-LAN Service type
Metro Ethernet Services Overview v1.2

19. Example Service using E-Line Service Type
Ethernet Virtual Private Line
Supports Service Multiplexed UNI
Point-to-Point VPN for site interconnectivity
Point-to-Point EVCs
Point-to-Point FR PVCs
Ethernet UNI
Service Multiplexed Ethernet UNI
FR UNI
FR UNI CE
FR CPE
MEN
MEN CE
FR CPE
FR CPE CE
Ethernet UNI
FR UNI
Ethernet Virtual Private Line using E-Line Service type
Frame Relay Analogy to E-Line Service
Metro Ethernet Services Overview v1.2

20. Example Service using E-Line Service Type
Ethernet Private Line
Dedicated UNIs for Point-to-Point connections
Storage SP
Point-to-Point EVCs (dedicated BW)
Storage SP
Dedicated TDM circuits
Ethernet UNI
OC-3
Ethernet UNI
DS1 CE CE
MEN
MEN CE
ISP
POP CE
ISP
POP
DS3
Ethernet UNI
Internet
Internet CE CE
Ethernet UNI
OC-3
Ethernet Private Line using E-Line Service type
Private Line Analogy to E-Line Service
Metro Ethernet Services Overview v1.2

21. Example Service using E-LAN Service Type
Transparent LAN Service
Transparent LAN Service (TLS) provides
Intra-company Connectivity
Full transparency of control protocols (BPDUs)
New VLANs added
without coordination with provider
VLANs
Sales
Customer Service
Engineering
Multipoint-to-Multipoint EVC
UNI 1
UNI 2
MEN
UNI 3
VLANs
Sales
Customer Service
VLANs
Engineering
TLS makes the MEN look like a LAN
UNI 4
VLANs
Sales
Metro Ethernet Services Overview v1.2

22. Metro Ethernet Services Overview v1.2
Ethernet SLAs
Many Enterprise customers will not use Metro Ethernet services unless:
There are SLAs with performance assurances
There is availability of service to all critical locations
Such enterprises will build private networks
Critical SLA Service Attributes
Bandwidth Profile
Service Performance
Enterprise customers require CoS-based SLAs with service performance assurances
Metro Ethernet Services Overview v1.2

23. Bandwidth Profiles defined in ETM
MEF has defined three bandwidth profiles
Ingress Bandwidth Profile Per Ingress UNI
Ingress Bandwidth Profile Per EVC
Ingress Bandwidth Profile Per CoS ID
4 parameters <CIR, CBS, EIR, EBS>
CIR/CBS determines frame delivery per service level objectives
EIR/EBS determines amount of excess frame delivery allowed
Metro Ethernet Services Overview v1.2

24. Three Types of Bandwidth Profiles defined in ETM
EVC1
EVC1
Ingress Bandwidth Profile Per EVC1
EVC2
EVC2
Ingress Bandwidth Profile Per Ingress UNI
UNI
UNI
Ingress Bandwidth Profile Per EVC2
EVC3
EVC3
Ingress Bandwidth Profile Per EVC3
CE-VLAN CoS 6
CE-VLAN CoS 4
EVC1
Ingress Bandwidth Profile Per CoS ID 6
CE-VLAN CoS 2
UNI
Ingress Bandwidth Profile Per CoS ID 4
Ingress Bandwidth Profile Per CoS ID 2
EVC2
Metro Ethernet Services Overview v1.2

25. Service Performance (QoS) defined in ETM
Service Performance Parameters
Availability
Frame Delay
Frame Jitter
Frame Loss
Service performance level to delivery determined via:
Per CoS ID, e.g., 802.1p user priority per EVC
Per UNI (port), i.e., 1 CoS for all EVCs at UNI
Metro Ethernet Services Overview v1.2

26. Example CoS-based Metro Ethernet SLA
E-Line Service
4 Classes of Service
CoS determined via 802.1p CoS ID
Common type of SLA used with CoS-based IP VPNs
Service Class
Service Characteristics
CoS ID
Bandwidth Profile per EVC per CoS ID
Service Performance
Premium
Real-time IP telephony or IP video applications
6, 7
CIR > 0
EIR = 0
Delay < 5ms
Jitter < 1ms
Loss < 0.01%
Silver
Bursty mission critical data applications requiring low loss and delay (e.g., Storage)
4, 5
EIR ≤ UNI Speed
Jitter = N/S
Bronze
Bursty data applications requiring bandwidth assurances
3, 4
Delay < 15ms
Loss < 0.1%
Standard
Best effort service
0, 1, 2
CIR=0
EIR=UNI speed
Delay < 30ms
Loss < 0.5%
Metro Ethernet Services Overview v1.2

27. Summary of Metro Ethernet Services
Enabled Service over Ethernet
Storage
Internet Access
IP VPN
IP Telephony
Video on Demand
Ethernet Connectivity Service
E-Line and E-LAN
(Virtual and Private)
Service Delivery Technology
Ethernet over Fiber
Ethernet over SONET/SDH
Ethernet over RPR
Ethernet over MPLS
Ethernet over WDM
Metro Ethernet Services Overview v1.2

28. Metro Ethernet Services Overview v1.2
Summary
Ethernet Services
Same Ethernet… just used in new way
E-Line and E-LAN Service types create
broad range of point-to-point and multipoint services
Ethernet Services Framework
Defines service attributes that define the service characteristics
Ethernet Services need CoS-based SLAs
to increase Enterprise usage for mission critical apps
Metro Ethernet Services Overview v1.2

29. References and Resources
Metro Ethernet Services – A Technical Overview
Bandwidth Profiles for Ethernet Services
MEF 1.0 “Ethernet Service Model, Phase 1”
Metro Ethernet Services for Enterprises
Business Case for Enterprise Metro Ethernet
Metro Ethernet Networks - A Technical Overview
Metro Ethernet Services Overview v1.2