1. WHY SHOULD YOU SELECT EOMPLS
AS THE TECHNOLOGY OF CHOICE
FOR A GREEN FIELD CE
DEPLOYMENT?
SEPTEMBER 2012
By Eng. Anuradha Udunuwara,
BSc.Eng(Hons), CEng, MIE(SL), MEF-CECP, MBCS, ITILv3 Foundation, MIEEE, MIEEE-CS, MIEE, MIET, MCS(SL), MSLAAS

2. Agenda
2
 Introduction
 Options
 Recommendations
 CEN requirements
(c) Anuradha Udunuwara

3. Introduction
3
 Assume a CSP with NO  CSP wants to use CE technology
aggregation network to build the aggregation
between the core and access. network.
 IP/MPLS has been a field
proven technology and CSP  CSP intends to
for the past several years deliver/transport/aggregate the
implemented an IP/MPLS services/traffic across the CEN in
based core network and has an E2E IP oriented architecture
built a team of experienced supporting the current and future
staff. demands.
(c) Anuradha Udunuwara

4. Intended Services
4
Enterprise and
corporate data Consumer services Wholesale services
services
• L3 VPN • IPTV) (multicast TV • Mobile
• L2 VPN and unicast VoD) backhauling
• L2 PP • Broadband • L2 VPN
Internet • L2 PP
• IP Voice
(c) Anuradha Udunuwara

5. Options
PBB / MAC in
PB / QinQ / IEEE PBB-TE / IEEE
Feature MAC / IEEE MPLS-TP IP/MPLS EoSDH
5 802.1ad 802.1Qay
802.1ah
Centralized Centralized
Control Plane Centralized Server MPLS
Server Server
Provisioning CLI, EMS CLI, EMS EMS/NMS only EMS/NMS only CLI, EMS EMS/NMS only
Multipoint support Yes Yes Yes Yes (with VPLS) Yes NO
CSP needs to learn all reduced MAC
MAC learning Not automatic Yes (with VPLS) Yes (VPLS) N/A
the MACs learning
Service Protection xSTP xSTP ERPS Not mature Note 1 50 ms, ring/mesh 50ms, ring
Operation SDH like SDH like SDH like
Addressing scheme Ethernet Ethernet Ethernet different Ethernet N/A
TE Poor Poor Good Good Good Poor
Note 1: RFC 6372 (MPLS-TP Survivability Framework) released on September 2011 (c) Anuradha Udunuwara

6. Options, cont
6
PB / QinQ / PBB / MAC in MAC PBB-TE / IEEE
Feature MPLS-TP EoMPLS EoSDH
IEEE 802.1ad / IEEE 802.1ah 802.1Qay
Maturity High Low Low Low High High
Interoperability High Low Low Low High High
Scalability Low High High High High Low
Separation of
High High High High High High
customer networks
Vendor stickiness Low High High High Low Low
(c) Anuradha Udunuwara

7. Recent standards for the IP/MPLS based CENs
7
 Broadband forum’s TR-
221 (Technical
Specifications for MPLS Important: IP/MPLS in the CEN is required to
support IP VPN and IP multicast features to
in Mobile Backhaul support 4G mobile services such as LTE (all IP
Networks) architecture).
 Broadband
forum’s, WT-224
(MPLS in Carrier
Ethernet Networks)
(c) Anuradha Udunuwara

8. Some facts
8
 To deliver the above mentioned multiple services on a
single CEN with required service features, IP/MPLS is the
most suited and matured technology.
 It is also needed to inter-op with the CSPs existing
IP/MPLS core, especially for E2E seamless services.
 It’s also noted that most of the access network uplinks are
Ethernet or becoming Ethernet, while SDH/PDH networks
are becoming outdated and obsolete. Hence investing on
SDH is pointless.
(c) Anuradha Udunuwara

9. Recommendations
9
 The CEN shall be Transmission Agnostic.
 Aggregation of topology - to reduce the numbers of physical interfaces required at higher levels of the transport
/ switching hierarchy.
 Consolidation of network and transport protocols - to reduce the complexity of logical interfaces required at
higher levels of the transport / switching hierarchy.
 To have different traffic types physically and logically aggregated, so that they can be transported by the Core
Network.
 Development of CEN shall be closely mapped to service development strategy.
 The CEN shall be EoMPLS based.
 All the network elements of different switching capacity and network shall have high availability features.
 The service delivery architecture within CEN shall be layer 2 based except for multicasting which shall be IP
multicasting. However layer 2 multicasting features shall be available for customer multicasting services.
 The services and equipment shall be certified with MEF.
 VRF shall NOT be brought to CEN level, unless it’s required for 4G RAN backhauling (LTE) in the future as
specified in Broadband forum TR-221.
(c) Anuradha Udunuwara

10. CEN requirements
10
 Availability
 Stability
 QoS
 Performance
 multicast support
 TDM support
 Management
 Security
(c) Anuradha Udunuwara

11. Availability (Resilience)
11
Hardware Component of CE Node High Availability mechanism
Route processor 1:1
Switching fabric 1:1
Power supply 1+1 Note 2
Power feed 1+1 Note 2
Cooling system 1+1 Note 2
Any other control plane module 1:1
Any other switching plane component 1:1
Note 2: single component shall be able to take the full load of the CE node
(c) Anuradha Udunuwara

12. Availability (Resilience), cont
12
 ITU-T G.8032 version 1 & 2 (ERPS) wherever Following software level high availability features shall be implemented;
 NSR for
 LDP
 RSVP TE
 BGP
 OSPF
 PIM-SM and PIM-SSM
 ISSU
 BFD requirement shall be analyzed for following in the future stage
 LDP
 RSVP
 BGP
 OSPF
 PIM-SM and PIM-SSM
 NSF requirement shall be analyzed in future stage.
(c) Anuradha Udunuwara

13. Stability
13
 Stability of the CEN and its NE are very
important. This should ensure consistent
performance of the NE.
 MTBF and MTTR values shall meet
99.999% node availability
requirements.
(c) Anuradha Udunuwara

14. QoS
14
 CE QoS model is essential to provide dynamic quality of service feature without
overbooking the bandwidth for applications. It should be able provide better service to
selected traffic, depending on the individual requirements of different types of service
and also to meet requirements in customer SLA.
 The CEN shall be able to handle Layer 2 (802.1Q), Layer 3 DSCP and MPLS EXP
QoS/CoS. The CEN/NEs need to support classifying, marking, remarking, scheduling,
shaping and policing for all the above QoS/CoS models at all egress and ingress ports
whether access side or network side.
 Within the CEN, the nodes shall be able to support at least 4 hardware queues for traffic
per port.
 The control and management traffic within the node shall be handled separately from the
user traffic.
 Hierarchical QoS shall be analyzed in future stages.
(c) Anuradha Udunuwara

15. Performance
15
 Scalability of the CEN determine by providing sufficient
bandwidth to be able to guarantee a committed level of
performance for the full service portfolio of end users.
CEN shall be designed to achieve the certain QoS
requirements/KPIs defined with the set of
services/products. The CEN must be able to handle
unpredictable surges in traffic, and appropriate load.
 The network utilization has to be maintained within 70% to
facilitate the introduction of services and for the
unpredictable surges in traffic.
(c) Anuradha Udunuwara

16. Multicasting
16
 To support IPTV and other multicast applications,
the CEN shall support IP multicast protocols.
 Layer 3 based (PIM) multicast technology is
preferred over Layer 2 technology for scalability
and flexibility reasons.
 Layer 2 multicasting features shall be available
for customer multicasting services.
(c) Anuradha Udunuwara

17. Supporting TDM services
17
 TDM services shall be supported in the form of
CES using Synchronous Ethernet or IEEE 1588v2
for frequency and time of day synchronization.
 At least E1 and STM-1 CES shall be supported.
 Enabling CES shall be done if the no. of TDM
services few compared to the Ethernet services. If
not, separate TDM equipment shall be used.
(c) Anuradha Udunuwara

18. Management
18
 All the CE elements should be able to address the management
domain requirements.
 The standard functional entities such as: Fault management,
Configuration management (Fulfillment support), Security
management, Performance management and Inventory
management on all Network Nodes will be required.
 For service management, the network and the nodes shall support
following Ethernet OAM standards;
 IEEE 802.1ag (CFM)
 IEEE 802.3ah (EFM)
(c) Anuradha Udunuwara

19. Security
19
 The CEN addresses the security which provides
confidentiality, integrity and availability of specific
services. The following areas have been identified
and will be equipped with necessary security
mechanisms,
 Node security
 Access security
 Interconnection security – UNI and I-NNI
 Protocol security – UNI and I-NNI
(c) Anuradha Udunuwara

20. Standardization
20
 MEF, the Broadband Forum, IETF, IEEE and ITU-T
are the main SDO with regard to the CEN.
 The EoMPLS is a field proven and matured
technology in implementing CENs. Though the
standards are available, CSP needs to standardize
this architecture and protocols. All the future
network developments and deployments in the
future need to align to these.
 It is recommended that CSP get involved with these
SDOs, especially the MEF and the Broadband
forum. It is also recommended that CSP get the
MEF certification for its services (E-Line, E-LAN, E-
Tree and E-Access) and use MEF compliant
equipment in the CEN (MEF 9- Ethernet Services at
the UNI, MEF 14- Traffic Management Phase 1).
 The diagram shows the MEF defined attributes for Source: MEF (http://metroethernetforum.org/page_loader.php?p_id=140
Carrier Ethernet.
(c) Anuradha Udunuwara

21. About the Author
21
Eng. Anuradha Udunuwara is a Chartered Engineer by profession based in Sri Lanka. He has nearly a decade
industry experience in strategy, architecture, engineering, design, plan, implementation and maintenance of CSP
Networks using both packet-switched (PS) and Circuit-Switched (CS) technologies, along with legacy to NGN
migration. Eng. Anuradha is a well-known in the field of CSP industry, both locally and internationally.
Graduated from University of Peradeniya, Sri Lanka in 2001 with an honors in Electrical & Electronic Engineering,
Eng. Anuradha is a corporate member of the Institution of Engineers Sri Lanka, a professional member of British
Computer Society, a member of Institution of Electrical & Electronic Engineers, a member of Institution of
Engineering & Technology (formerly Institution of Electrical Engineers), a member of the Computer Society of Sri
Lanka, a life member of Sri Lanka Association for the Advancement of Science, senior member of the Carrier
Ethernet Forum, member of the Internet Society, member of the Internet Strategy Forum, member of the Internet
Strategy Forum Network, member of the Ethernet Academy, member of the NGN/IMS forum and member of the
Peradeniya Engineering Faculty Alumni Association. He is also an ITIL foundation certified and the only MEF-CECP in
the country.
In his spare time Anuradha enjoys spending time with his family, playing badminton, photography, reading and
travelling.
He can be reached at udunuwara@ieee.org
(c) Anuradha Udunuwara

22. Abbreviations
22
4G 4th Generation MPLS Multi Protocol Label Switching
BFD Bidirectional Forwarding Detection MPLS-TP MPLS-Transport Profile
BGP Border Gateway Protocol ms milli second
CE Carrier Ethernet MTBF Mean Time Between Failures
CEN Carrier Ethernet Network MTTR Mean time to Repair
CES Circuit Emulation Service NE Network Element
CFM Connectivity Fault Management NMS Network Management System
CLI Command Line Interface NSF Non Stop Forwarding
CoS Class of Service NSR Non Stop Routing
CSP Communication Service Provider OAM Operation Administration and Maintenance
DSCP Differential Services Code Point OSPF Open Shortest Path First
E2E End to End PB Provider Bridging
EFM Ethernet in the First Mile PBB Provider Backbone Bridging
EMS Element Management System PDH Plesiochronous Digital Hierarchy
EoMPLS Ethernet over MPLS PIM-SM Protocol Independent Multicast-Sparse Mode
EoSDH Ethernet over SDH PP Point to Point
ERPS Ethernet Ring Protection Scheme QoS Quality of Service
EXP Experimental RAN Radio Access Network
IEEE Institution of Electrical & Electronic Engineers RSVP Resource reservation Protocol
IETF Internet Engineering Task Force SDH Synchronous Digital Hierarchy
I-NNI Internal Network to Network Interface SDO Standard Defining Organizations
IP Internet Protocol SLA Service Level Agreement
IPTV IP Television SSM Source Specific Multicast
ISSU In Service Software Upgrade STP Spanning Tree Protocol
ITU-T International Telecommunication Union - Standardization TDM Time Division Multiplexing
KPI Key Performance Indicator TE Traffic Engineering
L layer UNI User to Network Interface
LAN Local Area Network VoD Video on Demand
LDP Label Distribution Protocol VPLS Virtual Private LAN Service
LTE Long Term Evolution VPN Virtual Private Network
MAC Media Access Control VRF Virtual Routing and Forwarding instance
MEF Metro Ethernet Forum (c) Anuradha Udunuwara