The document discusses OpenStack networking deployment models. It describes the moderator and panelists for a discussion on the topic. The body examines different networking models used in OpenStack like Nova networking, Neutron network services, and overlay networks. It provides examples of how these models could be applied to different use cases with varying numbers of tenants and hosts. Finally, it poses questions the panelists might discuss around advising customers on model choices, integrating physical infrastructure, alternatives to switched VLAN models, and using BGP/MPLS in single data center solutions.

1. • Moderator
– Chris Marino, Cisco
• Panelists
– Nick Barcet, eNovance
– Rohit Agarwalla, Cisco
– Somik Behera, VMware
– Rudra Rugge, Juniper
© 2013 Cisco and/or its affiliates. All rights reserved.
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2. • Elements very rudimentary
• Configured directly by tenant
–
–
–
–
Networks
Subnets
Routers
Services
• Requirements drive complexity
–
–
–
–
Scalable Multi-tenancy
Tenant/app isolation
Topology/Service Insertion
Security
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3. • Nova Networking
– Flat, Flat/DHCP
• Bridge VMs out to physical network
– VLAN networking
• Isolated tenant virtual network
• Gateway to physical L3
• Neutron Network Service
– Nova style networks
– Overlay Networks
• Variety of overlay choices: VXLAN, GRE, STT, NVGRE
– Layer 3 Services
– Provider Networks
• Simple way to attach to existing VLANs
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4. • Web service/on-line property or Large site, single-tenant
– One giant app. Other smaller supporting apps. DevOps team
• Enterprise, single DC private cloud.
– A few dozen apps, 50% virtualized
• Large Enterprise IT
– Hundreds of apps, dozens of BUs with dev teams
– Multi-DC private cloud
• Cloud SP
– Public IaaS, VPC Offering, etc.
© 2013 Cisco and/or its affiliates. All rights reserved.
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5. OpenStack Networking Deployment Models
Number of
Tenants
Number of Hosts
Networking
Model
OpenStack
Module
Technology
Comments
W/S
None/One
Any
Flat, Provider
Networks
Nova-network or
Neutron
Linux Bridge, Physical
Network
Really simple, fast. Best
for lots of N/S traffic.
Ent
Less than 4K
1-2 racks
Isolated Tenant
VLANs
Nova-network or
Neutron
OVS, Trunked VLANs
Simple, fast. Limited
Ent
Less than 4K
1-2 racks
VLANs w/L3
Services
Neutron
+Host-based Agents
Software possible
bottleneck. Service
Insertion TBD
Ent
Less than 4K
1-2 racks
VLANs w/L3
Services
Neutron
+Top of Rack
Fast, Familiar. Routable
but L3 Services TBD
IT
More than 4K
Tens
Switched
Overlay
Neutron
Trunked VLANs
w/Tunnels
Not Simple. Host
Scalability Issues (STP).
IT
More than 4K
Hundreds
Fabric Overlay
Neutron
IP Fabric w/Tunnels
Single DC, Fabric
Controller needed
IT,
CSP
More than 4K
Thousands
Fabric Overlay
Neutron
IP Fabric w/Tunnels,
+BGP, +MPLS
Multi-zone, Hybrid/ Cloud
SP, Fabric Controller
needed
© 2013 Cisco and/or its affiliates. All rights reserved.
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6. 1. Nicholas: How do you advise customers when they have to
make these choices?
2. Rohit: Integrating into physical infra is always necessary, if
you’ve using a switched/VLAN model, what alternatives exist
for accessing physical network?
3. Somik: What would you say to someone that didn’t need 4K
tenants about taking on an overlay-based networking model?
4. Rudra: Can BGP/MPLS-VPN help in single data center solutions.
© 2013 Cisco and/or its affiliates. All rights reserved.
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