4g ip Networking technology development Niklas Carlheim

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Service Resiliency ITU-T SG15 Q9 Activities
Ghani Abbas
Ericsson
25th.,June, 2012
Geneva
Workshop - Disaster Relief
Systems and Network Resilience and Recovery
Topics
› Q9/15 Task
› Network Objectives and Requirements
› Approved Recommendations
› Protection Architectures
› Recommendations under development
› Network Restoration
› Protection schemes – interworking and guidelines
› Summary
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Q9/15 – Network Protection and
Restoration Work
- One of the task is addressing enhanceMENT to
Transport equipment functionality
Recommendations to provide Survivability
capabilities as well as addressing multi-layer
survivability interactions.
- The work covers all transport technologies
SDH, ATM, OTN, Ethernet and MPLS-TP including
interaction with protection at data/packet
layers
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Protection: Network Objectives
and Requirements
› Protection against one (or more) defects/failures
› Protection switching to be completed in less than 50ms
› Protection switching is invoked by LOS and OAM defects
› Various architecture schemes – linear, 1+1, 1:1, 1:n, uni
and bi-directional, ring and mesh
› Revertive and non-revertive
› Automatic Protection Switching (APS) protocol
› APS messages are prioritized
› APS is exercised to ensure satisfactory operation
› External operator commands are supported
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Protection Switching - APPROVED
Recommendations
-Linear protection
- Generic : G.808.1
- OTN : G.873.1
- Ethernet : G.8031
- MPLS-Tp: G.8131?
- Ring Protection
- Generic : G.808.2
- OTN : G.873.2
- Ethernet : G.8032
- MPLS-T : G.8132?
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1:1 and 1+1 Protection Architectures
- Fast (sub 50ms) switching
- Protects against fibre cuts and often interface cards failures
Equipment A
Worker Fibres
Equipment B
1:1
Protection Fibres
Equipment A
Worker Fibres
Equipment B
1+1
Protection Fibres
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Ring Protection
- Fast (sub 50ms) switching
- Optimised protection for ring architectures
Protection fibres
Worker fibres
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X
Failure
occurs
Current Work
› Shared Mesh protection
– Generic : G.smp
– Packet?
- OTN: G.otnsmp
› Inter-working of currently ITU SG15 standardised
Schemes
› Guidelines/Use cases of protection schemes
› Network scenarios and used cases for Ethernet Ring
protection schemes
Commercial in confidence | © Ericsson AB 2010 | 2012-06-25 | Page 8
Protection Interworking
- InterworkinG
of currently ITU SG15
standardised Schemes
- eg. G.8032/ G.8031, G.873.1/G.8032 interworking
etc
-Guidelines/Use cases of protection schemes
- Network scenarios and used cases for
EtherNET protection schemes
- focus on MBH applications and G.8032 and
G.8031 scenarios
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Protection Interworking ..1/2
G.8032/G.8031 Interworking Example
G.8032
G.8032
Distributed G.8031
Domain 1
Domain 2
Domain 3
G.8032
G.8032
Distributed G.8031
Domain 1
Domain 2
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Domain 3
Protection Interworking …2/2
G.8032 /G.873.1 Interworking Example
G.8032
G.8032
Distributed G.873.1
Domain 2
Domain 1
G.8032
Domain 3
G.8032
Distributed G.873.1
Domain 1
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Domain 2
Domain 3
Shared Mesh Protection (SMP) Current status
› Q9/15 is developing a generic Recommendation for SMP
› The main objective for SMP is to reduce operating cost by
sharing protection resources instead of dedicated protection
resources
› SMP operates independent of control plane
› A technology specific ODU SMP protection scheme based on
generic SMP is also being considered.
Commercial in confidence | © Ericsson AB 2010 | 2012-06-25 | Page 12
SMP Concept
Node A
Node B
Node A
Node B
Working 1
PS1
Working 1
PS2
Node C
Node D
Node C
PS1
PS3
Node E
PS4
Node D
PS3
PS5
Node F
Node E
PS4
Working 2
Cross-connect controller
PS2
PS5
Node F
Working 2
Protection segment
Bridge and selector functions
Protection segment
› 1 protection segment is shared by multiple protection paths
› The protection connection should be configured to reserve protection resource in
advance
› Switching activation is based on data plane
Commercial in confidence | © Ericsson AB 2010 | 2012-06-25 | Page 13
Important Aspects of SMP
Over-subscription:: “Each
timeslot may be used by
multiple connections”
Preemption:: “If the
working channel suffers
failure and its setup
priority is higher than
current one on the
protection channel, the
channel on the protection
gets chucked out!”
Working Connection X
B
C
A
D
Protecting Connection X’
E
F
G
Protecting Connection Y’
H
K
1:N Protection: with
multiple protection
requests, the channel with
highest preference level will
take over.”
I
J
Working Connection Y
L
M
Protecting Connection Y’’
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N
Protection and Restoration
› Most existing networks use pre-planned protection
– Network resource centrally controlled
– Protection pre-allocated and predicable
› Restoration
– Initially sets up worker only
– Protection occurs dynamically on failure
– Effectively statistical and non-deterministic
– Protection Bandwidth is shared between many workers
– Generally Control Plane is involved in the restoration scheme
Commercial in confidence | © Ericsson AB 2010 | 2012-06-25 | Page 15
Network Restoration
› Traditional protection is fixed
– Pre-calculated by a central manager
– Operation fixed and predictable
– Network equipment has no network topology awareness
› Restoration protection is dynamic
– Only worker traffic is set up
– Shared protection - protection calculated dynamically on failure
› Restoration is fundamentally different approach requiring
–
–
–
–
–
Network topology discovery
Routing algorithms
Peer to peer signalling
Traffic engineering
More cost effective – Protection Bandwidth is shared by many workers
Commercial in confidence | © Ericsson AB 2010 | 2012-06-25 | Page 16
Restoration Protection
1.3.Circuit
set upnode
A to B
Originating
4. Originating node
calculates a new path
signals new path set up
2. Failure occurs
X
A
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B
Restoration Protection
5 Circuit restored.
X
A
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B
Ethernet Ring Protection
Supplement – Current Status
The supplement will provide network scenarios,
Usage guidelines and examples for G.8032
applicability.
It will describe the following:
› ERP in support of network applications (e.g., Mobile
Backhaul, Business Services, etc.)
› ERP in support of Ethernet services
› Interconnected ERP ring examples
› Guidelines for configuration and management procedures
for ERP
› End-to-end network/service resiliency involving ERP
Commercial in confidence | © Ericsson AB 2010 | 2012-06-25 | Page 19
End-to-end service resilience in
Ethernet ring protection
G.8032 - An example for
Access links
Access links
G
end-to-end service resilience
C
E
A
UNI
B
ERP
D
UNI
F
H
End to end resilience is needed
K
C
End-to-end service resilience
over interconnected rings
A
L
Sub-Ring
D
J
Major Ring
M
Commercial in confidence | © Ericsson AB 2010 | 2012-06-25 | Page 20
Sub-Ring
H
G
E
F
B
Summary
› A number of approved recommendations define fast
protection schemes covering all transport technologies
› Shared Mesh Protection work is progressing well
› Network restoration using control plane for various
transport technologies is also standardized
Commercial in confidence | © Ericsson AB 2010 | 2012-06-25 | Page 21
Commercial in confidence | © Ericsson AB 2010 | 2012-06-25 | Page 22
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