INTERNET-DRAFT Luyuan Fang
Intended Status: Standards track John Evans
Expires: April 18, 2014 David Ward
Rex Fernando
John Mullooly
Cisco
Ning So
Tata Communications
Nabil Bitar
Verizon
Maria Napierala
AT&T
October 18, 2013
BGP/MPLS IP VPN Virtual CE
draft-fang-l3vpn-virtual-ce-02
Abstract
This document describes the architecture and solutions of using
virtual Customer Edge (vCE) of BGP IP MPLS VPN. The solution is aimed
at providing efficient service delivery capability through CE
virtualization, and is especially beneficial in virtual Private Cloud
(vPC) environments for extending BGP/MPLS IP VPN into tenant virtual
Data Center containers.
Status of this Memo
This Internet-Draft is submitted to IETF in full conformance with the
provisions of BCP 78 and BCP 79.
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http://www.ietf.org/1id-abstracts.html
The list of Internet-Draft Shadow Directories can be accessed at
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1 Terminology . . . . . . . . . . . . . . . . . . . . . . . . 4
1.2 Problem statement . . . . . . . . . . . . . . . . . . . . . 5
1.3 Scope of the document . . . . . . . . . . . . . . . . . . . 6
2. Virtual CE Architecture and Reference Model . . . . . . . . . . 6
2.1 Virtual CE . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.2 Architecture . . . . . . . . . . . . . . . . . . . . . . . . 7
3. Control Plane . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.1 vCE Control Plane . . . . . . . . . . . . . . . . . . . . . 10
4. Forwarding Plane . . . . . . . . . . . . . . . . . . . . . . . 10
4.1 Forwarding between vCE and PE/vPE . . . . . . . . . . . . . 11
4.2 Forwarding between vCE and VM . . . . . . . . . . . . . . . 11
5. Addressing and QoS . . . . . . . . . . . . . . . . . . . . . . 11
5.1 Addressing . . . . . . . . . . . . . . . . . . . . . . . . . 11
5.2 QoS . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
6. Management plane . . . . . . . . . . . . . . . . . . . . . . . 12
6.1 Network abstraction and management . . . . . . . . . . . . . 12
6.2 Service VM Management . . . . . . . . . . . . . . . . . . . 12
7. Orchestration and IP VPN inter-provisioning . . . . . . . . . . 12
7.1 DC Instance to WAN BGP/MPLS IP VPN instance "binding"
Requirements . . . . . . . . . . . . . . . . . . . . . . . . 12
7.2. Provisioning/Orchestration . . . . . . . . . . . . . . . . 13
7.2.1 vCE Push model . . . . . . . . . . . . . . . . . . . . . 13
7.2.1.1 Inter-domain provisioning vCE Push Model . . . . . . 14
7.2.1.2 Cross-domain provisioning vCE Push Model . . . . . . 14
7.1.1 vCE Pull model . . . . . . . . . . . . . . . . . . . . . 15
8. Security Considerations . . . . . . . . . . . . . . . . . . . . 16
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 16
10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 16
10.1 Normative References . . . . . . . . . . . . . . . . . . . 16
10.2 Informative References . . . . . . . . . . . . . . . . . . 17
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11. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 18
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1. Introduction
In the typical enterprise BGP/MPLS IP VPN [RFC4364] deployment, the
Provider Edge (PE) and Customer Edge (CE) are physical routers which
support the PE and CE functions. With the recent development of cloud
services, using virtual instances of PE or CE functions, which reside
in a compute device such as a server, can be beneficial to emulate
the same logical functions as the physical deployment model but now
achieved via cloud based network virtualization principles. This
would be considered as part of the Network functions Virtualization
(NFV) effort.
This document describes BGP/MPLS IP VPN virtual CE (vCE) solutions,
while Virtual PE (vPE) concept and implementation options are
discussed in [I-D.fang-l3vpn-virtual-pe],
[I-D.ietf-l3vpn-end-system]. vPE and vCE solutions provide two
avenues to realize network virtualization.
1.1 Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
Term Definition
----------- --------------------------------------------------
AAA Authentication, Authorization, and Accounting
ACL Access Control List
AS Autonomous Systems
ASBR Autonomous Systems Border Router
BGP Border Gateway Protocol
CE Customer Edge
DB Data Base
DMZ Demilitarized Zone, a.k.a. perimeter networking
FE Front End
FTP File Transfer Protocol
GRE Generic Routing Encapsulation
HTTP Hypertext Transfer Protocol
Hypervisor Virtual Machine Manager
I2RS Interface to Routing System
LDAP Lightweight Directory Access Protocol
MP-BGP Multi-Protocol Border Gateway Protocol
NAT Network Address Translation
NVGRE Network Virtualization using GRE
PE Provider Edge
QinQ Provider Bridging, stacked VLANs
RR Route Reflector
SDN Software Defined Network
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SLA Service Level Agreement
SMTP Simple Mail Transfer Protocol
ToR Top of the Rack switch
vCE virtual Customer Edge Router
vLB virtual Load Balancer
VM Virtual Machine
VLAN Virtual Local Area Network
vPE virtual Provider Edge Router
VPN Virtual Private Network
vSG virtual Security Gateway
VXLAN Virtual eXtensible Local Area Network
WAN Wide Area Network
Virtual CE (vCE): A virtual instance of the Customer Edge (CE)
routing function which resides in one or more network or compute
devices. For example, the vCE data plane may reside in an end device,
such as a server, and as co-resident with application Virtual
Machines (VMs) on the server; the vCE control plane may reside in the
same device or in a separate entity such as a controller.
End device: A device where Guest OS, Host OS/Hypervisor,
applications, VMs, and virtual router may reside.
Network Container/Tenant Container: An abstraction of a set of
network and compute resources which can be physical and virtual,
providing the cloud services for a tenant. One tenant can have more
than one Tenant Containers.
Zone: A logical grouping of VMs and service assets within a tenant
container. Different security policies may be applied within and
between zones.
DMZ: Demilitarized zone, a.k.a. perimeter networking. It is often a
machine or a small subnet that sits between a trusted internal
network, such as a corporate private LAN, and an un-trusted external
network, such as the public Internet. Typically, the DMZ contains
devices accessible to Internet traffic, such as Web (HTTP) servers,
FTP servers, SMTP (e-mail) servers and DNS servers.
1.2 Problem statement
With the growth of cloud services and the increase in the number of
CE devices, routers/switches, and appliances, such as Firewalls (FWs)
and Load Balancers (LBs), that need to be supported, it is beneficial
to virtualize the Data Center tenant container. The virtualized
container can increase resource sharing, optimize routing and
forwarding of inter-segment and inter-service traffic, and allow
simplified design, provisioning, and management.
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The following two aspects of the virtualized Data Center tenant
container for the IP VPN CE solution are discussed in this document.
1. Architecture re-design for virtualized DC.
The optimal architecture of the virtualized container includes
virtual CE, virtual appliances, and application VMs. All these
functions are co-residents on virtualized servers. CEs and appliances
can be created and removed easily on demand, and the virtual CE can
interconnect the virtual appliances (e.g., FW, LB, NAT), applications
(e.g., Web, App., and DB) in a co-located fashion for simplicity,
routing/forwarding optimization, and easier service chaining.
Virtualizing these functions on a per-tenant basis provides
simplicity for the network operator in regards to managing per tenant
service orchestration, tenant container moves, capacity planning
across tenants and per-tenant policies.
2. Provisioning/orchestration. Two issues need to be addressed:
a) The provisioning/orchestration system of the virtualized data
center need to support VM life cycle and VM migration.
b) The provisioning/orchestration systems of the DC and the WAN
networks need to be coordinated to support end-to-end BGP/MPLS IP VPN
from DC to DC or from DC to enterprise remote offices in the same
VPN. The DC and the WAN network are often operated by separate
departments, even if they belong to the same provider. Today, the
process of inter-connecting is often slow and painful, and automation
is highly desirable.
1.3 Scope of the document
As the majority (all in some networks) of applications are IP, this
vCE solution is focusing on IP VPN solutions to cover the most common
cases and keep matters as simple as possible.
2. Virtual CE Architecture and Reference Model
2.1 Virtual CE
As described in [RFC4364], IP uses a "peer model" - the customers'
edge routers (CE routers) exchange routes with the Service Provider's
edge routers (PE routers); the CEs do not peer with each other. MP-
BGP [RFC4271, RFC4760] is used between the PEs (often with RRs) which
have a particular VPN attached to them to exchange the VPN routes. A
CE sends IP packets to the PE; no VPN labels for packets forwarded
between CE and PE.
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A virtual CE (vCE) is a software instance of BGP/MPLS IP VPN CE
function which can reside in ANY network or compute devices. For
example, a vCE MAY reside in an end device, such as a server in a
Data Center, where the application VMs reside.
Using the virtual CE model, the CE functions CAN easily co-located
with the VM/applications, e.g., in the same server. This allows
tenant inter-segment and inter-service routing to be optimized.
Likewise the vCE can be in a separate server (in the same DC rack or
across racks) than the application VMs, in which case VMs would
typically use standard L2 technologies to access the vCE via the DC
network.
Similar to the virtual PE solution, the control and forwarding of a
virtual CE can be on the same device, or decoupled and reside on
different physical devices. The provisioning of a virtual CE,
associated applications, and the tenant network container can be
supported through DC orchestration systems.
Unlike a physical or virtual PE which can support multi-tenants, a
physical or virtual CE supports a single tenant only. A single tenant
CAN use multiple physical or virtual CEs. An end device, such as a
server, CAN support one or more vCE(s). While the vCE is defined as a
single tenant device, each tenant can have multiple logical
departments which are under the tenant administrative control,
requiring logical separation, this is the same model as today's
physical CE deployments.
vCE and vPE are complimentary approaches for extending IP VPN into
tenant containers. In the vCE solution, there is no BGP/MPLS IP VPN
within the data center or other type of service network, the vCE can
connect to the PE which is a centralized BGP/MPLS IP VPN PE/ASBR/DC
Gateway, or connect to distributed vPE on a server or on the Top of
the Rack switch (ToR). vCE can be used to extend the existing SP
managed CE solution to create new cloud enabled services and provide
the same topological model and features that are consistent with the
physical CE systems.
2.2 Architecture
Figure 1 illustrates the topology where vCE is resident in the
servers where the applications are hosted.
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.''---'''---''.
( )
( IP/MPLS )
( WAN )
WAN '--,,,_,,,--'
----------------|----------|------------------
Service/DC | |
Network +-------+ +-------+
|Gateway|---|Gateway|
| PE | | PE |
+-------+ +-------+
| ,---. |
.---. ( '.---.
( ' ' ')
(' Data Center )
(. Fabric .)
( ( ).--'
/ ''--' '-''--' \
/ / \ \
+-------+ +---+---+ +-------+ +-------+
| vCE | |vCE|vCE| | vCE | |vCE|vCE|
+---+---+ +---+---+ +---+---+ +---+---+
|VM |VM | |VM |VM | |VM |VM | |VM |VM |
+---+---+ +---+---+ +---+---+ +---+---+
|VM |VM | |VM |VM | |VM |VM | |VM |VM |
+---+---+ +---+---+ +---+---+ +---+---+
End Device End Device End Device End Device
Figure 1. Virtualized Data Center with vCE
Figure 1 above illustrate a vCE solution in a virtualized Data Center
with application VMs on the servers. One or more vCEs MAY be used on
each server.
The vCEs logically connect to the PEs/Gateway to join the particular
BGP/MPLS IP VPN which the tenant belongs to. Gateway PEs connect to
the BGP/MPLS IP VPN in the WAN network for inter-DC and DC to
enterprise VPN sites connection. The server physically connects to
the DC Fabric for packet forwarding.
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,---. ,---.
.--.( ) .--.( )
( ' '.---. ( ' '.---.
(' L3VPN ) (' Internet )
'..( ).' '..( ).'
'--'---'' '--'---''
+---+ +---+ +---+ +---+
|PE | |PE | | R | | R |
+---+ +---+ +---+ +---+
| | | |
""""""""""""""""""|"""""""|""""""""""""""|"""""""|"""""""""""""""""
" End Device | | +----+ | "
" (e.g. a server) +-------+-----+ +----|vSG |----+ "
" | | +----+ "
" +----+ "
" +---------------------|vCE |-----------+ "
" | +----+ | "
" +----+ | +----+ | | +----+ "
" |vLB |-| |vLB |--+-----------+ +--|vLB | "
" +----+ | +----+ | | +----+ "
" | | +----+ | "
" | | +------|vSG |-+------+ "
" | | | +----+ | "
" '''''''|'''''''''''|''''' ''''''|'''''''''|''''''''''|''''''''' "
" ' +--------+ +--------+ ' ' +-------+ +-------+ +-----------+ ' "
" ' | Apps/ | | Apps/ | ' ' | Apps/ | | Apps/ | |Apps |Apps | ' "
" ' | VMs | | VMs | ' ' | VMs | | VMs | |VMs |VMs | ' "
" ' | | | | ' ' | | | | |ZONE3|ZONE4| ' "
" ' | Public | |Protect-| ' ' | | | | +-----+-----+ ' "
" ' | Zone | | ed FE | ' ' | ZONE1 | | ZONE2 | |Apps |Apps | ' "
" ' | (DMZ) | | | ' ' | | | | |VMs |VMs | ' "
" ' | | | | ' ' | | | | |ZONE5|ZONE6| ' "
" ' +--------+ +--------+ ' ' +-------+ +-------+ +-----------+ ' "
" ' Front-end Zone ' ' Back-end Zone ' "
" ' ' ' ' "
" ''''''''''''''''''''''''' ''''''''''''''''''''''''''''''''''''' "
"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
Figure 2. A Virtualized Container with vCE in an End Device
An end device shown in Figure 2 is a physical server supporting
multiple virtualized appliances and applications, and hosts multiple
client VMs.
In the traditional deployment, the topology often involves multiple
physical CEs, physical Security Gateways and Load Balancers residing
in the same Data Center.
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The virtualized approach provides the benefit of reduced number of
physical devices, simplified management, optimal routing due to the
co-location of vCE, services, and client VMs.
While the above diagram represents a simplified view of all of the
tenant service and application VMs residing in the same physical
server, the above model can also be represented with the VMs spread
across many physical servers and the DC network would provide the
physical inter-connectivity while the vCE and the VMs connected to
the vCE form the logical connections.
3. Control Plane
3.1 vCE Control Plane
The vCE control plane can be distributed or centralized.
1) Distributed control plane
vCE CAN exchange BGP routes with PE or vPE for the particular
BGP/MPLS IP VPN as described in [RFC4364]. The vCE must support BGP
if this approach is used.
The advantage of using distributed protocols is to avoid single point
of failure and bottleneck. Service chaining can be easily and
efficiently supported in this approach.
BGP as PE-CE protocol is used in majority deployment in typical
Enterprise BGP/MPLS IP VPN PE-CE connections. BGP supports rich
policy compared to other alternatives.
2) Static routing. It is also used in Enterprise BGP/MPLS IP VPN PE-
CE connections based on past observation. It MAY be used if the
operator prefers.
2. Using controller approach
Controller can be used as part of the Software Defined Network (SDN)
approach. A controller can be distributed or centralized, or
physically distributed and logically centralized. The controller
performs the control plane functions, and sends instructions to the
vCE on the end devices to configure the data plane.
This requires standard interface to routing system (I2RS). The
Interface to Routing System (I2RS) is work in progress in IETF
[I-D.ietf-i2rs-architecture], [I-D.ietf-i2rs-problem-statement].
4. Forwarding Plane
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4.1 Forwarding between vCE and PE/vPE
No MPLS forwarding is required between PE and CE in typical PE-CE
connection scenarios, though MPLS label forwarding is required for
implementing Carriers' Carrier (CSC) model.
IPv4 and IPv6 packet forwarding MUST be supported.
Native fabric CAN be used to support isolation between vCEs to PE
connections.
Examples of native fabric include:
- VLANs [IEEE 802.1Q], Virtual Local Area Network
- IEEE 802.1ad [IEEE 802.1ad]/QinQ, Provider Bridge
Or overlay segmentation with better scalability:
- VXLANs, Virtual Extensible LAN, work in progress in IETF,
[I-D.mahalingam-dutt-dcops-vxlan].
- NVGRE, Network Virtualization using GRE, work in progress in
IETF [I-D.sridharan-virtualization-nvgre].
4.2 Forwarding between vCE and VM
If the vCE and the VM that the vCE is connecting are co-located in
the same server, the connection is internal to the server, no
external protocol involved.
If the vCE and the VM that the vCE is connecting are located in
different devices, standard external protocols are needed. The
forwarding can be native or overlay techniques as listed in the above
sub-section.
5. Addressing and QoS
5.1 Addressing
IPv4 and IPv6 addressing MUST be supported.
IP address allocation for vCEs and applications/client:
1) IP address MAY be assigned by central management/provisioning
with predetermined blocks through planning process.
2) IP address MAY be obtained through DHCP server.
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Address space separation: The IP addresses used for clients in the
BGP/MPLS IP VPNs in the DC SHOULD be in separate address blocks
outside the blocks used for the underlay infrastructure of the DC.
The purpose is to protect the DC fabric from being attacked if the
attacker gain access of the tenant VPNs.
5.2 QoS
Differentiated Services [RFC2475] Quality of Service (QoS) is
standard functionality for physical CEs and MUST be supported on vCE.
This is important to ensure seamless end-to-end SLA from BGP/MPLS IP
VPN in the WAN into service network/Data center. The use of MPLS
Diffserv tunnel model Pipe Mode (RFC3270) with explicit null LSP must
be supported.
6. Management plane
6.1 Network abstraction and management
The use of vCE with single tenant virtual service instances can
simplify management requirements as there is no need to discover
device capabilities, track tenant dependencies and manage service
resources.
vCE North bound interface SHOULD be standards based.
The programmatic interface are currently under definition in the
IETF's Interface to Routing Systems (I2RS) initiative,
[I-D.ietf-i2rs-architecture], [I-D.ietf-i2rs-problem-statement].
vCE element management MUST be supported, it can be in the similar
fashion as for physical CE, without the hardware aspects.
6.2 Service VM Management
Service VM Management SHOULD be hypervisor agnostic, e.g., on demand
service VMs turning-up SHOULD be supported.
The management tools SHOULD be open standards.
7. Orchestration and IP VPN inter-provisioning
7.1 DC Instance to WAN BGP/MPLS IP VPN instance "binding" Requirements
- MUST support service activation in the physical and virtual
environment.
For example, assign VLAN to correct VRF.
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- MUST support per VLAN Authentication, Authorization, and Accounting
(AAA).
The PE function is an OAM boundary.
- MUST be able to apply other policies to VLAN.
For example, per VLAN QOS, ACLs.
- MUST ensure that WAN BGP/MPLS IP VPN state and DC state are
dynamically synchronized.
Ensure that there is no possibility of customer being connected to
the wrong VRF. For example, remove all tenant state when service an
instance is terminated.
- MUST integrate with existing WAN BGP/MPLS IP VPN provisioning
processes.
- MUST scale to 10,000 or higher tenant service instances.
- MUST cope with rapid (sub minute) tenant mobility.
- SHOULD support automated cross provisioning accounting correlation
between WAN BGP/MPLS IP VPN and Cloud/DC for the same tenant.
- MAY support Automated cross provisioning state correlation between
WAN BGP/MPLS IP VPN and Cloud/DC for the same tenant.
7.2. Provisioning/Orchestration
There are two primary approaches for IP VPN provisioning - push and
pull, both CAN be used for provisioning/orchestration.
7.2.1 vCE Push model
Push model: It is a top down approach - push IP VPN provisioning from
network management system or other central control provisioning
systems to the IP VPN network elements.
This approach supports service activation and it is commonly used in
the existing BGP/MPLS IP VPN enterprise deployment. When extending
BGP/MPLS IP VPN solution into the Cloud/DC, it MUST support off-line
accounting correlation between the WAN BGP/MPLS IP VPN and the
Cloud/DC IP VPN for the tenant, the systems SHOULD be able to bind
interface accounting to particular tenant. It MAY requires offline
state correlation as well, for example, bind interface state to
tenant.
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7.2.1.1 Inter-domain provisioning vCE Push Model
Provisioning process:
1) Cloud/DC orchestrator configures vCE.
2) Orchestrator initiates WAN IP VPN provisioning; passes connection
IDs (e.g., of VLAN/VXLAN/NVGRE) and tenant context to WAN IP VPN
provisioning systems.
3) WAN IP VPN provisioning system provisions PE VRF and other
policies per normal enterprise IP VPN provisioning processes.
This model requires the following:
- The DC orchestration system or the WAN IP VPN provisioning system
know the topology inter-connecting the DC and WAN VPN. For
example, which interface on the WAN core device connects to which
interface on the DC PE.
- Offline state correlation.
- Offline accounting correlation.
- Per SP integration.
Dynamic BGP session between PE/vPE and vCE MAY be used to automate
the PE provisioning in the PE-vCE model, that will remove the needs
for PE configuration. Other protocols can be used for this purpose
as well, for example, use Enhanced Interior Gateway Routing Protocol
(EIGRP) for dynamic neighbour relationship establishment.
The dynamic routing prevents the needs to configure the PEs in PE-vCE
model.
Caution: This is only under the assumption that the DC provisioning
system is trusted and could support dynamic establishment of PE-vCE
BGP neighbor relationships, for example, the WAN network and the
cloud/DC belongs to the same SP.
7.2.1.2 Cross-domain provisioning vCE Push Model
Provisioning Process:
1) Cross-domain orchestration system initiates DC orchestration.
2) DC orchestration system configures vCE.
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3) DC orchestration system passes back VLAN/VXLAN/NVGRE and tenant
context.
to cross-domain orchestration system
4) Cross-domain orchestration system initiates WAN IP VPN
provisioning.
5) WAN IP VPN provisioning system provisions PE VRF and other
policies as per normal enterprise IP VPN provisioning processes.
This model requires the following:
- Cross-domain orchestration system knows the topology connecting the
DC and WAN IP VPN, for example, which interface on core device
connects to which interface on DC PE.
- Offline state correlation.
- Offline accounting correlation.
- Per SP integration.
7.1.1 vCE Pull model
Pull model: It is a bottom-up approach - pull from network elements
to network management/AAA based upon data plane or control plane
activity. It supports service activation, this approach is often used
in broadband deployment. Dynamic accounting correlation and dynamic
state correlation are supported. For example, session based
accounting is implicitly includes tenant context state correlation,
as well as session based state which implicitly includes tenant
context.
Inter-domain Provisioning:
Process:
1) Cloud/DC orchestration system configures vCE.
2) Cloud/DC orchestration system primes WAN IP VPN provisioning/AAA
for new service, passes connection IDs (e.g., VLAN/VXLAN/NVGRE) and
tenant context WAN IP VPN provisioning systems.
3) Cloud/DC PE detects new VLAN, send Radius Access-Request.
4) Radius Access-Accept with VRF and other policies.
This model requires VLAN/VXLAN/NVGRE information and tenant context
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to be passed on a per transaction basis. In practice, it may simplify
to use DC orchestration updating LDAP directory.
Auto accounting correlation and auto state correlation are supported
in this model.
8. Security Considerations
When vCE is created on a network or compute device, such as a server,
the operator MUST evaluate the following conditions: Is server owned
by the the operator? Is it using a managed CE model? How to
authenticate? The ownership of the device where the vCE resides has
major implication on the design, it determines where the boundary is
between the trusted and un-trusted zones.
When a vCE in DC connecting BGP MPLS IP VPN in the WAN, the amount of
information can be exchanged across the two domains through auto-
provisioning will be different depending on if the DC and WAN are
under same administrative domain. Only limited and/or abstracted
information should be exchanged if the two domains are owned by
different SPs. Additional authentication, and other security
mechanism need to be deployed to prevent accidental or malicious
attach from the other domain.
In addition, the connection authentication is very important for the
pull models.
And the virtual FW placement needs to be carefully designed to
protect against attacks.
9. IANA Considerations
None.
10. References
10.1 Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A
Border Gateway Protocol 4 (BGP-4)", RFC 4271, January
2006.
[RFC4364] Rosen, E. and Y. Rekhter, "BGP/MPLS IP Virtual Private
Networks (VPNs)", RFC 4364, February 2006.
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[RFC4760] Bates, T., Chandra, R., Katz, D., and Y. Rekhter,
"Multiprotocol Extensions for BGP-4", RFC 4760, January
2007.
[I-D.ietf-l3vpn-end-system] Marques, P., Fang, L., Pan,
P., Shukla, A., Napierala, M., "BGP-signaled end-system
IP/VPNs", draft-ietf-l3vpn-end-system, work in progress.
[I-D.fang-l3vpn-virtual-pe] Fang, L., et al., "BGP IP VPN Virtual
PE", draft-fang-l3vpn-virtual-pe, work in progress.
[IEEE 802.1ad] IEEE, "Provider Bridges", 2005.
[IEEE 802.1q] IEEE, "802.1Q - Virtual LANs", 2006.
[IEEE 802.1ag] IEEE "802.1ag - Connectivity Fault
Management", 2007.
10.2 Informative References
[RFC2475] Blake, S., Black, D., Carlson, M., Davies, E., Wang, Z.,
and W. Weiss, "An Architecture for Differentiated
Services", RFC 2475, December 1998.
[I-D.ietf-i2rs-architecture] Atlas, A., Halpern, J., Hares, S., Ward,
D., and T Nadeau, "An Architecture for the Interface to
the Routing System", draft-ietf-i2rs-architecture, work in
progress.
[I-D.ietf-i2rs-problem-statement] Atlas, A., Nadeau, T., and Ward D.,
"Interface to the Routing System Problem Statement",
draft-ietf-i2rs-problem-statement, work in progress.
[I-D.mahalingam-dutt-dcops-vxlan]: Mahalingam, M, Dutt, D., et al.,
"A Framework for Overlaying Virtualized Layer 2 Networks
over Layer 3 Networks" draft-mahalingam-dutt-dcops-vxlan,
work in progress.
[I-D.sridharan-virtualization-nvgre]: SridharanNetwork, M., et al.,
"Virtualization using Generic Routing Encapsulation",
draft-sridharan-virtualization-nvgre, work in progress.
11. Acknowledgement
The authors would like to thank Vaughn Suazo for his review and
comments.
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Authors' Addresses
Luyuan Fang
Cisco
111 Wood Ave. South
Iselin, NJ 08830
Email: luyuanf@gmail.com
John Evans
Cisco
16-18 Finsbury Circus
London, EC2M 7EB, UK
Email: joevans@cisco.com
David Ward
Cisco
170 W Tasman Dr
San Jose, CA 95134
Email: wardd@cisco.com
Rex Fernando
Cisco
170 W Tasman Dr
San Jose, CA
Email: rex@cisco.com
John Mullooly
Cisco
111 Wood Ave. South
Iselin, NJ 08830
Email: jmullool@cisco.com
Ning So
Tata Communications
Plano, TX 75082, USA
Email: ning.so@tatacommunications.com
Nabil Bitar
Verizon
40 Sylvan Road
Waltham, MA 02145
Email: nabil.bitar@verizon.com
Maria Napierala
AT&T
200 Laurel Avenue
Middletown, NJ 07748
Email: mnapierala@att.com
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