Control-Plane Slicing Methodsin Multi-Tenant Software Defined Networks

IFIP/IEEE International Symposium on Integrated Network ManagementMay 11, 2015

Ottawa, Canada

C. Argyropoulos, K. Giotis, G. Androulidakis, D. Kalogeras, V. Maglaris

Network Management & Optimal Design Laboratory (NETMODE)School of Electrical & Computer Engineering

National Technical University of Athens

S. Mastorakis

Computer Science DepartmentUniversity of California, Los Angeles (UCLA)

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Virtualization in multi-tenant Networks

Large-scale multi-tenant environments rely on Network Virtualization technologies

Tenants request dedicated network slices Scalability issues are mitigated Widely-accepted and/or proprietary solutions include:

□ Layer 2/3 VPN□ VXLAN□ NVGRE□ STT

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Network Virtualization in SDNs

Network virtualization is taking advantage of SDNs: Leverage on Control and Data-plane decoupling

□ OpenFlow protocol Tenants apply their own forwarding logic

□ ByoC – Bring your own Controller

Open issue: Efficient substrate slicing

amongst multiple tenants

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OpenFlow-based Virtual Networks

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Flow-grouping as a Virtualization method

Grouping of flows: VLAN-based (1 VLAN ID/tenant) MAC-based (in cloud infrastructures) to pinpoint the VMs

location Port-based for service-oriented networks

Network virtualization based on Flowspace assignment

Conflict resolution for tenant requests

Isolated virtual networks Prevent overlapping Flowspaces

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Network Virtualization Architectures (1)

OF Proxy Controller

Flowspace Slicing Policy Engine: Policy-based flowspace slicing

Slicing Layer: Policy enforcement using flowspace rules

Tenant Layer: Forwarding Logic

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Network Virtualization Architectures (1)

Network Hypervisor

Flowspace Slicing Policy Engine: Policy-based flowspace slicing

Slicing Layer: Policy enforcement using flowspace rules

Virtualization Layer: Delegate Slicing

Identifiers Abstraction Expose Virtual Topo

Tenant Layer: Forwarding Logic

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Slicing Policies (1)

Domain-wide Slicing: {TenantID, VlanID} Vlan ID is considered to be the Network Slice Identifier All packets marked with a specific Vlan ID are forwarded to the respective

tenant’s Controller by the Proxy Controller

Switch-wide Slicing: {TenantID, VlanID, SwitchID} VlanID and SwitchID are used to identify packets belonging to a specific slice Requests are forwarded by the proxy Controller to the tenant, based on the

VlanID and the SwitchID

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Slicing Policies (2)

Port-wide Slicing: {TenantID, VlanID, SwitchID, PortID} VlanID, SwitchID and PortID are used to match slices with a specific tenant Requests are forwarded according to the afformentioned identifiers Requires one flowspace rule for each port bounded to a specific tenant

Switch A

1 2

5 3

4

Tenant KVLAN i

Tenant KVLAN i Tenant L

VLAN i

Tenant LVLAN i

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Evaluation Approach

We used real graphs from Internet2/OS3E and GÉANT We created Virtual Network requests, mapping:

Simple paths (case of Virtual Network providers) Disjoint paths Star topologies (case of CDN providers)

We created mixes of mapping requests: Mix1: 2% disjoint paths, 49% simple paths, 49% star topologies (bounded –

predefined Packet ID) Mix2: 2% disjoint paths, 29% simple paths, 69% star topologies (bounded) Mix3: 2% disjoint paths, 29% simple paths, 69% star topologies (bounded) Mix4: 2% disjoint paths, 29% simple paths, 69% star topologies (unbounded)

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Evaluation (1)

4,000 requests

16,000 requests

Acceptance ratio of VN requests on Internet2

topologies

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Evaluation (2)

• Acceptance ratio for Mix2 requests

• Switch-wide & port-wide number of rules,

normalized by the domain-wide rules

Flow

spac

e ru

les/

Dom

ain-

wid

e Fl

owsp

ace

rule

s

Number of nodes

Acceptance Ratio

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Evaluation (3)Control Plane resource consumption(using FlowVisor OF proxy Controller)

GÉANT topology

Requests

(mix2)

Rules(port-wide)

Time (ms)Memory

(Mbytes)

1.000 17Κ 4.7 6722.000 45Κ 5.0 18524.000 100Κ 5.4 40506.000 150Κ 5.5 61027.000 180Κ 5.9 7500

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THANK YOU!

Kostas Giotiscoyiotis@netmode.ntua.gr