Network Working Group L. Yong
Internet Draft Huawei
Category: Informational M. Toy
Comcast
A. Isaac
Bloomberg
V. Manral
Hewlett-Packard
L. Dunbar
Huawei
Expires: January August 2015 February 5, 2015 July 1, 2014
Use Cases for DC Data Center Network Virtualization Overlays
draft-ietf-nvo3-use-case-04
draft-ietf-nvo3-use-case-05
Abstract
This document describes DC Data Center (DC) Network Virtualization over
Layer 3 (NVO3) use cases that may can be potentially deployed in various data
centers and apply serve to different applications.
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Table of Contents
1. Introduction ................................................ 3 Introduction...................................................3
1.1. Contributors ........................................... 4
1.2. Terminology ............................................ 4 Terminology...............................................4
2. Basic Virtual Networks in a Data Center ..................... 4 Center........................4
3. Interconnecting DC Virtual Network and External Networks .... 6 Network Interconnection........6
3.1. DC Virtual Network Access via Internet ................. 6 Internet....................6
3.2. DC VN and Enterprise Sites interconnected via SP WAN ... 7 VPN Interconnection......................7
4. DC Applications Using NVO3 .................................. 8 NVO3.....................................8
4.1. Supporting Multi Multiple Technologies and Applications in a DC . 9 Applications.........8
4.2. Tenant Network with Multi-Subnets or across multi DCs .. 9 Multiple Subnets......................9
4.3. Virtualized Data Center (vDC) ......................... 11 (vDC)............................11
5. OAM Considerations ......................................... 12 Summary.......................................................12
6. Summary .................................................... 13
7. Security Considerations .................................... 14
8. Considerations.......................................13
7. IANA Considerations ........................................ 14
9. Acknowledgements ........................................... 14
10. References ................................................ 14
10.1. Considerations...........................................13
8. References....................................................13
8.1. Normative References ................................. 14
10.2. References.....................................13
8.2. Informative References ............................... 15 References...................................13
Contributors.....................................................14
Acknowledgements.................................................15
Authors' Addresses ............................................ 15 Addresses...............................................15
1. Introduction
Server Virtualization has changed IT the Information Technology (IT)
industry in terms of the efficiency, cost, and the speed in of providing a
new applications and/or services.
However, today's data center However traditional Data Center
(DC) networks have limited support for some limits in supporting cloud applications and
multi tenant networks.[NVO3PRBM] networks [RFC7364]. The goal of DC Network Virtualization Overlays, i.e. NVO3,
Overlays in DC is to decouple the communication among tenant systems
from DC physical infrastructure networks and to allow one physical
network infrastructure to provide: 1) multi-
tenant
o Multi-tenant virtual networks and traffic isolation among the
virtual networks over the same physical network; 2) independent network.
o Independent address spaces in individual virtual networks such as
MAC, IP, TCP/UDP etc;
3) etc.
o Flexible VMs or Virtual Machines (VM) and/or workload placement
including the ability to move them from servers server to other servers server without
requiring VM address and configuration change and the ability
doing a hot move in which with no disruption to the live application
running on VM. VMs.
These characteristics will of NVO3 help address the issues in today's that cloud
applications [NVO3PRBM]. face in Data Centers [RFC7364].
An NVO3 network is necessary to can interconnect with a another physical network,
where tenant systems attach to i.e.,
not the both networks. physical network that the NVO3 network is over. For examples: example:
1) DCs that migrates migrate toward NVO3 solution will be done in steps; 2) a
lot of
many DC applications are served serve to Internet cloud users which exist who are on
physical networks; 3) some applications are CPU bound like such as Big
Data analytics and may not run on virtualized resources.
This document is to describe describes general NVO3 use cases that apply to various
data centers. Three types of the use cases described here are:
o Basic NVO3 virtual networks in DC. a DC (Section 2). All TS of the Tenant
Systems (TS) in virtual networks are located within one DC. The Virtual
individual virtual networks can be either L2 Layer 2 (L2) or
L3. Layer 3
(L3). The number of Virtual Networks to be virtual networks supported in by NVO3 in a DC is
usually more
much higher than what traditional VLAN based virtual networks
[IEEE 802.1Q] can support. The This case is often referred as to the
DC East-West traffic.
o Virtual networks that span across multiple Data Centers or and/or to
customer premises, i.e. i.e., a Virtual Network virtual network that has connects some nodes
tenant systems in a DC and other nodes in other places. interconnects another virtual or physical
network outside the data center. An enterprise customer may use a
traditional VPN provided by a carrier VPN or an IPsec tunnel over Internet to connect
communicate its systems in the TSs across multiple DCs and customer
premises. DC. This is described in Section 3.
o DC applications or services that may use NVO3. NVO3 (Section 4). Three
scenarios are described: 1) use NVO3 and other network
technologies to build a tenant network; 2) construct several
virtual networks as a tenant network; 3) apply NVO3 to a
virtualized DC (vDC).
The document uses the architecture reference model defined in
[NVO3FRWK]
[RFC7365] to describe the use cases.
1.1. Contributors
Vinay Bannai
PayPal
2211 N. First St,
San Jose, CA 95131
Phone: +1-408-967-7784
Email: vbannai@paypal.com
Ram Krishnan
Brocade Communications
San Jose, CA 95134
Phone: +1-408-406-7890
Email: ramk@brocade.com
1.2. Terminology
This document uses the terminologies defined in [NVO3FRWK], [RFC7365] and
[RFC4364]. Some additional terms used in the document are listed
here.
CPE: Customer Premise Equipment
DMZ: Demilitarized Zone. A computer or small subnetwork sub-network that sits
between a trusted internal network, such as a corporate private LAN,
and an un-trusted external network, such as the public Internet.
DNS: Domain Name Service
NAT: Network Address Translation
VIRB: Virtual Integrated Routing/Bridging
Note that a virtual network in this document is an overlay a virtual network instance. in
DC that is implemented with NVO3 technology.
2. Basic Virtual Networks in a Data Center
A virtual network may exist within in a DC. The network DC enables a communication among Tenant
Systems (TS). A TS may can be a physical server/device or a virtual
machine (VM) on a server. server, i.e., end-device [RFC7365]. A network
virtual edge Network
Virtual Edge (NVE) may can be co-located with a TS, i.e. i.e., on a same end-
device, or reside on a different device, e.g. e.g., a top of rack switch
(ToR). A virtual network has a unique virtual network identifier
(may (can be local or
global unique) for an NVE to properly differentiate
it from other virtual networks. unique or local significant at NVEs).
Tenant Systems attached to the same NVE may belong to the same or
different virtual network. The multiple virtual networks can be
constructed in a way so that the policies are enforced when the TSs
in one virtual network communicate with the TSs in other virtual networks. An NVE provides tenant traffic
forwarding/encapsulation and obtains tenant systems reachability
information from Network Virtualization Authority (NVA)[NVO3ARCH]. Furthermore in a
DC operators may can construct many tenant virtual networks that have no
communication in between at all. In this case, each tenant virtual network
may use
can have its own address spaces such as MAC and IP. One tenant
network may have DC operators can
also construct multiple virtual networks in a way so that the
policies are enforced when the TSs in one or more virtual network
communicate with the TSs in other virtual networks. This is referred
to as Distributed Gateway [NVO3ARCH].
A Tenant System may also can be configured with one or multiple addresses and
participate in multiple virtual networks, i.e. i.e., use the same or
different address in different virtual networks. For examples, a TS may
Tenant System can be a NAT GW or a firewall and connect to more than
one virtual network.
Network Virtualization Overlay in this context means that a virtual
network is implemented with an overlay technology, i.e. i.e., tenant
traffic from
an is encapsulated at its local NVE and carried by a tunnel
over DC IP network to another NVE where the packet is sent via a tunnel between decapsulated
prior to sending to a pair of
NVEs.[NVO3FRWK] target tenant system. This architecture
decouples tenant system address
scheme space and configuration from the
infrastructure's, which brings a great flexibility for VM placement
and mobility. This also makes The technology results the transit nodes in the
infrastructure not aware of the existence of the virtual networks.
One tunnel may carry the traffic belonging to different virtual
networks; a virtual network identifier is used for traffic
demultiplexing.
A virtual network may be an L2 or L3 domain. The TSs attached to an
NVE may can belong to different virtual networks that may be are either in L2
or L3. A virtual network may can carry unicast traffic and/or
broadcast/multicast/unknown traffic from/to tenant systems. There
are several ways to transport virtual network BUM traffic.[NVO3MCAST] traffic
[NVO3MCAST].
It is worth to mention two distinct cases here. regarding to NVE location.
The first is that TSs and an NVE are co-located on a same end device,
which means that the NVE can be made aware of the TS state at any time
via internal API. The second is that TSs and an NVE are remotely connected, i.e.
connected reside on
different devices that connect via a switched network or point-to-point link. In wire; in this case, a protocol
is necessary for NVE to know TS state. state [NVO3HYVR2NVE].
One virtual network may connect can provide connectivity to many TSs that attach
to many different NVEs. NVEs in a DC. TS dynamic placement and mobility
results in frequent changes in of the binding between a TS and NVE bindings. an NVE.
The TS reachbility update mechanism mechanisms need be fast enough to so that the
updates do not cause any service interruption. The capability of
supporting many TSs in a virtual network and many more virtual
networks in a DC is critical for NVO3 solution.
If a virtual network spans across multiple DC sites, one design is
to allow the network seamlessly to span across the sites without DC
gateway routers' termination. In this case, the tunnel between a
pair of NVEs may in turn can be tunneled over carried within other intermediate tunnels
over of the
Internet or other WANs, or the intra DC and inter DC tunnels are can be
stitched together to form an end-to-end a tunnel between the pair of NVEs that are
in different DC sites. Both cases will form one virtual network
across DCs. multiple DC sites.
3. Interconnecting DC Virtual Network and External Networks Network Interconnection
For customers (an enterprise or individuals) who utilize the DC
provider's compute and storage resources to run their applications,
they need to access their systems hosted in a DC through Internet or
Service Providers' WANs. Wide Area Networks (WAN). A DC provider may can
construct a virtual network that connect provides the connectivity to all
the resources designated for a customer and
allow allows the customer to
access their resources via a virtual gateway (vGW). This, in turn,
becomes the case of interconnecting a DC virtual network and the
network at customer site(s) via Internet or WANs. Two use cases are
described here.
3.1. DC Virtual Network Access via Internet
A customer can connect to a DC virtual network via Internet in a
secure way. Figure 1 illustrates this case. A virtual network is
configured on NVE1 and NVE2 and two NVEs are connected via an L3 IP
tunnel in the Data Center. A set of tenant systems are attached to
NVE1 on a server. The NVE2 resides on a DC Gateway device. NVE2
terminates the tunnel and uses the VNID on the packet to pass the
packet to the corresponding vGW entity on the DC GW. A customer can
access their systems, i.e. i.e., TS1 or TSn, in the DC via Internet by
using IPsec tunnel [RFC4301]. The IPsec tunnel is configured between
the vGW and the customer gateway at customer site. Either static
route or BGP iBGP may be used for peer routes. routes update. The vGW provides IPsec
functionality such as authentication scheme and encryption. Note
that: 1) some encryption; iBGP
protocol is carried within the IPsec tunnel. Some vGW features are
listed below:
o Some vGW functions such as firewall and load balancer may
also can be
performed by locally attached network appliance devices; 2) devices.
o The virtual network in DC may use different address space than
external users, then vGW need needs to provide the NAT function; 3) more function.
o More than one IPsec tunnels can be configured for the redundancy; 4) redundancy.
o vGW
may can be implemented on a server or VM. In this case, IP
tunnels or IPsec tunnels may can be used over DC infrastructure.
o DC operators need to construct a vGW for each customer.
Server+---------------+
| TS1 TSn |
| |...| |
| +-+---+-+ | Customer Site
| | NVE1 | | +-----+
| +---+---+ | | CGW |
+------+--------+ +--+--+
| *
L3 Tunnel *
| *
DC GW +------+---------+ .--. .--.
| +---+---+ | ( '* '.--.
| | NVE2 | | .-.' * )
| +---+---+ | ( * Internet )
| +---+---+. | ( * /
| | vGW | * * * * * * * * '-' '-'
| +-------+ | | IPsec \../ \.--/'
| +--------+ | Tunnel
+----------------+
DC Provider Site
Figure 1 - DC Virtual Network Access via Internet
3.2. DC VN and Enterprise Sites interconnected via SP WAN
An enterprise company may lease the VM and storage resources hosted
in the 3rd party DC to run its applications. For example, the
company may run its web applications at 3 party sites but run
backend applications in own DCs. The Web applications and backend
applications need to communicate privately. The 3 party DC may
construct one or more virtual networks to connect all VMs and
storage running the VPN Interconnection
In this case, an Enterprise Web applications. The company may buy
a p2p private tunnel such as VPWS from a SP customer wants to use Service Provider
(SP) WAN VPN [RFC4364] [EVPN] to interconnect its site sites and the a
virtual network at the 3rd party site. A protocol is
necessary for exchanging the reachability between two peering points
and the traffic are carried over the tunnel. If an enterprise has
multiple sites, it may buy multiple p2p tunnels to form a mesh
interconnection among the sites and the third party in DC site. This
requires each site peering with all other sites for route
distribution.
Another way to achieve multi-site interconnection is to use Service Provider (SP) constructs a VPN services, in which each for
the enterprise customer. Each enterprise site only peers with a SP PE
site. A PE.
The DC Provider and VPN SP may Service Provider can build a DC virtual
network (VN) and VPN independently. The VPN interconnects several enterprise
sites independently and interconnects the DC virtual network at DC site, i.e. VPN site. The DC VN and SP VPN interconnect
via a local link or a tunnel. tunnel between DC GW and WAN PE devices. The
control plan interconnection options between the VN and VPN are
described in RFC4364 [RFC4364]. In Option A with VRF-LITE [VRF-LITE],
both ASBRs, i.e., DC GW and SP PE PE, maintain a routing/forwarding
table, and perform the table lookup in forwarding. In Option B, DC GW
ASBR and SP PE ASBR do not maintain the forwarding table, it only
maintains the VN and VPN identifier mapping, and swap the
identifier
identifiers on the packet in the forwarding process. Both option A
and B requires tunnel termination. In option C, DC GW the VN and SP PE VPN use
the same identifier for VN identifier, and VPN, and just Both ASBRs perform the tunnel stitching, i.e.
i.e., change the tunnel end points. Each option has pros/cons (see
RFC4364) and has been deployed in SP networks depending on the
applications. The BGP protocols may can be used in these options for
route distribution. Note that if the provider DC is the SP Data Center, the
DC GW and SP PE in this case may can be on merged into one
device. device that
performs the interworking of the VN and VPN.
This configuration allows the enterprise networks communicating to
the tenant systems attached to the VN in a provider DC provider site without
interfering with DC provider underlying physical networks and other
virtual networks in the DC. The enterprise may can use its own address
space on the tenant systems in the VN. The DC provider can manage which VM and storage attachment
attaching to the VN. The enterprise customer manages what
applications to run on the VMs in the VN. See VN without the knowledge of
VMs location in the DC. (See Section 4 for more.
The interesting feature more)
Furthermore, in this use case is that the VN and compute
resource are managed by case, the DC provider. The DC operator can place
them at any server without notifying the enterprise and WAN SP
because the DC physical network is completely isolated from the
carrier and enterprise network. Furthermore, the DC operator may move the VMs
assigned to the enterprise from one sever to another in the DC
without the enterprise customer awareness, i.e. i.e., no impact on the
enterprise 'live' applications running these resources. Such
advanced features technologies bring DC providers great benefits in serving offering
cloud applications but also add some requirements for NVO3 [NVO3PRBM]. [RFC7364] as
well.
4. DC Applications Using NVO3
NVO3 technology brings DC operators the flexibility in designing and
deploying different applications in an end-to-end virtualization
overlay environment, where the operators no longer need to worry
about the constraints of the DC physical network configuration when
creating VMs and configuring a virtual network. DC provider may use
NVO3 in various ways and also use it in the conjunction with other
physical networks in DC for many reasons. a reason. This section just highlights
some use cases.
4.1. Supporting Multi Multiple Technologies and Applications in a DC
Most likely servers deployed in a large data center are rolled in at
different times and may have different capacities/features. Some
servers may be virtualized, some may not; some may be equipped with
virtual switches, some may not. For the ones equipped with
hypervisor based virtual switches, some may support VxLAN [VXLAN] [RFC7348]
encapsulation, some may support NVGRE encapsulation [NVGRE], and
some may not support any types of encapsulation. To construct a
tenant network among these servers and the ToR switches, it may operators
can construct one NVO3 virtual network and one traditional VLAN
network; or two virtual networks that one uses VxLAN encapsulation
and another uses NVGRE.
In these cases, a gateway device or virtual GW is used to
participate in multiple two virtual networks. It performs the packet
encapsulation/decapsulation translation and may also perform address mapping or
translation, and etc.
A data center may be also constructed with multi-tier zones. Each
zone has different access permissions and run runs different
applications. For example, the three-tier zone design has a front
zone (Web tier) with Web applications, a mid zone (application tier)
with service applications such as payment and booking, and a back
zone (database tier) with Data. External users are only able to
communicate with the Web application in the front zone. In this case,
the communication between the zones must pass through the security
GW/firewall. One virtual network may can be configured in each zone and
a GW is used to interconnect two virtual networks. networks, i.e., two zones.
If individual zones use the different implementations, the GW needs
to support these implementations as well.
4.2. Tenant Network with Multi-Subnets or across multi DCs Multiple Subnets
A tenant network may contain multiple subnets. The DC physical
network needs to support the connectivity for many tenant networks.
The
inter-subnets inter-subnet policies may be placed at some designated gateway
devices only. Such design requires the inter-subnet traffic to be
sent to one of the gateways first for the policy checking, which may
cause traffic hairpin at the gateway in a DC. It is desirable that
an NVE can hold some policies and be able to forward inter-subnet
traffic directly. To reduce NVE burden, the hybrid design may be
deployed, i.e. i.e., an NVE can perform forwarding for the selected inter-
subnets
inter-subnets and the designated GW performs for the rest. For
example, each NVE performs inter-subnet forwarding for a tenant, and
the designated GW is used for inter-subnet traffic from/to the
different tenant networks.
A tenant network may span across multiple Data Centers that are in distance.
difference locations. DC operators may configure an L2 VN within
each DC and an L3 VN between DCs for a tenant network. For this
configuration, the virtual L2/L3 gateway can be implemented on DC GW
device. Figure 2 illustrates this configuration.
Figure 2 depicts two DC sites. The site A constructs one L2 VN, say
L2VNa, on NVE1, NVE2, and NVE3. NVE1 and NVE2 reside on the servers
which host multiple tenant systems. NVE3 resides on the DC GW device.
The site Z has similar configuration with L2VNz on NVE3, NVE4, and
NVE6. One L3 VN, say L3VNx, is configured on the NVE5 at site A and
the NVE6 at site Z. An internal Virtual Interface of Routing and
Bridging (VIRB) is used between L2VNI and L3VNI on NVE5 and NVE6,
respectively. The L2VNI is the MAC/NVE mapping table and the L3VNI
is the IP prefix/NVE mapping table. A packet to the NVE5 from L2VNa
will be decapsulated and converted into an IP packet and then
encapsulated and sent to the site Z. The policies can be checked at
VIRB.
Note that the L2VNa, L2VNz, and L3VNx in Figure 2 are overlay NVO3 virtual
networks.
NVE5/DCGW+------------+ +-----------+ NVE6/DCGW
| +-----+ | '''''''''''''''' | +-----+ |
| |L3VNI+----+' L3VNx '+---+L3VNI| |
| +--+--+ | '''''''''''''''' | +--+--+ |
| |VIRB | | VIRB| |
| +--+---+ | | +---+--+ |
| |L2VNIs| | | |L2VNIs| |
| +--+---+ | | +---+--+ |
+----+-------+ +------+----+
''''|'''''''''' ''''''|'''''''
' L2VNa ' ' L2VNz '
NVE1/S ''/'''''''''\'' NVE2/S NVE3/S'''/'''''''\'' NVE4/S
+-----+---+ +----+----+ +------+--+ +----+----+
| +--+--+ | | +--+--+ | | +---+-+ | | +--+--+ |
| |L2VNI| | | |L2VNI| | | |L2VNI| | | |L2VNI| |
| ++---++ | | ++---++ | | ++---++ | | ++---++ |
+--+---+--+ +--+---+--+ +--+---+--+ +--+---+--+
|...| |...| |...| |...|
Tenant Systems Tenant Systems
DC Site A DC Site Z
Figure 2 - Tenant Virtual Network with Bridging/Routing
4.3. Virtualized Data Center (vDC)
An Enterprise DC's Data Center today may deploy routers, switches, and
network appliance devices to construct its internal network, DMZ,
and external network access and access; it may have many servers and storage
running various applications. A With NVO3 technology, a DC Provider may
can construct a virtualized DC over its DC infrastructure and offer
a virtual DC service to enterprise customers. A vDC at DC Provider
site provides the same capability as a physical DC. DC at the customer
site. A customer manages what and how applications to run in
the its
vDC. Instead of using many hardware devices to do it, with the
network virtualization overlay technology, DC operators may build
such vDCs on top of a common DC infrastructure for many such
customers and Provider can further offer different network service
functions to a vDC. The network service functions may include
firewall, DNS, load balancer, gateway, and etc. The network virtualization overlay further enables potential
for vDC mobility when a customer moves to different locations
because vDC configuration is decouple from the infrastructure
network.
Figure 3 below illustrates one scenario. For the simple
illustration, it only shows the L3 VN or L2 VN as virtual routers or
switches. in abstraction. In
this case, example, DC Provider operators create several L2 VNs (L2VNx,
L2VNy, L2VNz) in Figure 3 to group the tenant systems together per application
basis, create one L3 VN, e.g. e.g., VNa for the internal routing. A net device (may be
network function, firewall and gateway, runs on a VM or server) runs firewall/gateway
applications and server that
connects to the L3VNa and Internet. is used for inbound and outbound traffic
process. A load balancer (LB) is used in L2 VNx. A VPWS p2p tunnel VPN is also built
between the gateway and enterprise router. Enterprise customer runs
Web/Mail/Voice applications on VMs at the provider DC site; lets site that can
spread out on many servers; the users at Enterprise site to access the
applications via running in the VPN tunnel and
Internet provider DC site via a gateway at the Enterprise site; let VPN; Internet
users access the these applications via the gateway in gateway/firewall at the
provider DC.
The
Enterprise customer decides which applications are accessed by
intranet only and which by both intranet and extranet and configures
the proper security policy and gateway function. function at firewall/gateway.
Furthermore a an enterprise customer may want multi-zones in a vDC
(See section 4.1) for the security and/or set different QoS levels
for the different applications.
This
The vDC use case requires the NVO3 solution to provide the DC operator
operators an easy and quick way to create a VN and NVEs for any design and vDC
design, to quickly allocate TSs and assign TSs to VNIs on a NVE they attach to, easily to set up virtual
topology and place or configure policies on an NVE or VMs that run
net services, the corresponding VN, and support VM mobility. Furthermore a DC operator
and/or customer should be able
to view the illustrate vDC topology and access manage/configure individual virtual components in the vDC. Either DC provider or
tenant can provision virtual components elements
in the vDC. It is desirable
to automate vDC via the provisioning process and have programmability. vDC topology.
Internet ^ Internet
|
^ +--+---+
| | GW |
| +--+---+
| |
+-------+--------+ +--+---+
|Firewall/Gateway+--- VPN-----+router|
+-------+--------+ +-+--+-+
| | |
...+.... |..|
+-------: L3 VNa :---------+ LANs
+-+-+ ........ |
|LB | | | Enterprise Site
+-+-+ | |
...+... ...+... ...+...
: L2VNx : : L2VNy : : L2VNx :
....... ....... .......
|..| |..| |..|
| | | | | |
Web Apps Mail Apps VoIP Apps
Provider DC Site
firewall/gateway and Load Balancer (LB) may run on a server or VMs
Figure 3 - Virtual Data Center by Using NVO3 (vDC)
5. OAM Considerations
NVO3 brings the ability for a DC provider to segregate tenant
traffic. A DC provider needs to manage and maintain NVO3 instances.
Similarly, the tenant needs to be informed about underlying network
failures impacting tenant applications or the tenant network is able
to detect both overlay and underlay network failures and builds some
resiliency mechanisms.
Various OAM and SOAM tools and procedures are defined in [IEEE
802.1ag], [ITU-T Y.1731], [RFC4378], [RFC5880], [ITU-T Y.1564] for
L2 and L3 networks, and for user, including continuity check,
loopback, link trace, testing, alarms such as AIS/RDI, and on-demand
and periodic measurements. These procedures may apply to tenant
overlay networks and tenants not only for proactive maintenance, but
also to ensure support of Service Level Agreements (SLAs).
As the tunnel traverses different networks, OAM messages need to be
translated at the edge of each network to ensure end-to-end OAM.
6. Summary
The
This document describes some general potential use cases of NVO3 in
DCs. The combination of these cases should will give operators flexibility
and capability to design more sophisticated cases for various purposes. cloud
applications.
DC services may vary from infrastructure as a service (IaaS),
platform as a service (PaaS), to software as a service (SaaS), in
which the network virtualization overlay is NVO3 virtual networks are just a portion of an
application service. such services.
NVO3 decouples the service
construction/configurations from the DC network infrastructure
configuration, and helps deployment of higher level services over
the application.
NVO3's underlying network provides the tunneling between NVEs uses tunnel technique so that two NVEs appear as one hop to
each other. other in a virtual network. Many tunneling technologies can
serve this function. The tunneling may in turn be tunneled over
other intermediate tunnels over the Internet or other WANs. It is also possible that intra DC and inter DC tunnels are
stitched together to form an end-to-end tunnel between two NVEs.
A DC virtual network may be accessed by external users in a secure
way. Many existing technologies can help achieve this.
NVO3 implementations may vary. Some DC operators prefer to use
centralized controller to manage tenant system reachbility in a
tenant
virtual network, other prefer to use distributed protocols to
advertise the tenant system location, i.e. associated NVEs. For the
migration and special requirement, the different solutions may apply
to one tenant network in a DC. i.e., NVE location. When a
tenant network spans across multiple DCs and WANs, each network
administration domain may use different methods to distribute the
tenant system locations. Both control plane and data plane
interworking are necessary.
7.
6. Security Considerations
Security is a concern. DC operators need to provide a tenant a
secured virtual network, which means one tenant's traffic isolated
from the other tenant's traffic and non-tenant's traffic; they also need
to prevent DC underlying network from any tenant application
attacking through the tenant virtual network or one tenant
application attacking another tenant application via DC networks.
infrastructure network. For example, a tenant application attempts
to generate a large volume of traffic to overload DC underlying
network. The NVO3 solution has to address these issues.
8.
7. IANA Considerations
This document does not request any action from IANA.
9. Acknowledgements
Authors like to thank Sue Hares, Young Lee, David Black, Pedro
Marques, Mike McBride, David McDysan, Randy Bush, Uma Chunduri, and
Eric Gray for the review, comments, and suggestions.
10.
8. References
10.1.
8.1. Normative References
[RFC4364] Rosen, E. and Y. Rekhter, "BGP/MPLS IP Virtual Private
Networks (VPNs)", RFC 4364, February 2006.
[IEEE 802.1ag] "Virtual Bridged Local Area Networks - Amendment 5:
Connectivity Fault Management", December 2007.
[ITU-T G.8013/Y.1731] OAM Functions and Mechanisms for Ethernet
based Networks, 2011.
[ITU-T Y.1564] "Ethernet service activation test methodology", 2011.
[RFC4378] Allan, D., Nadeau,
[RFC7364] Narten, T., "A Framework for Multi-Protocol
Label Switching (MPLS) Operations and Management (OAM)",
RFC4378, February 2006
[RFC4301] Kent, S., "Security Architecture et al "Problem Statement: Overlays for the Internet
Protocol", rfc4301, December 2005
[RFC5880] Katz, D. Network
Virtualization", RFC7364, October 2014.
[RFC7365] Lasserre, M., Motin, T., and Ward, D., "Bidirectional Forwarding Detection
(BFD)", rfc5880, June 2010.
10.2. et al, "Framework for DC
Network Virtualization", RFC7365, October 2014.
8.2. Informative References
[EVPN] Sajassi, A., Ed., Aggarwal, R., Bitar, N., Isaac, A. and J.
Uttaro, "BGP MPLS Based Ethernet VPN", Work in Progress,
draft-ietf-l2vpn-evpn-11, work in progress.
[IEEE 802.1Q] IEEE, "IEEE Standard for Local and metropolitan area
networks -- Media Access Control (MAC) Bridges and Virtual
Bridged Local Area", IEEE Std 802.1Q, 2011.
[NVO3HYVR2NVE] Li, Y., et al, "Hypervisor to NVE Control Plane
Requirements", draft-ietf-nvo3-hpvr2nve-cp-req-01, work in
progress.
[NVGRE] Sridharan, M., "NVGRE: Network Virtualization using Generic
Routing Encapsulation", draft-sridharan-virtualization-
nvgre-03,
nvgre-07, work in progress.
[NVO3ARCH] Black, D., et al, "An Architecture for Overlay Networks
(NVO3)", draft-ietf-nvo3-arch-00, work in progress.
[NVO3PRBM] Narten, T., et al "Problem Statement: Overlays for
Network Virtualization", draft-ietf-nvo3-overlay-problem-
statement-04, work in progress.
[NVO3FRWK] Lasserre, M., Motin, T., and et al, "Framework for DC
Network Virtualization", draft-ietf-nvo3-framework-04, draft-ietf-nvo3-arch-02, work in progress.
[NVO3MCAST] Ghanwani, A., "Multicast Issues "Framework of Supporting Applications
Specific Multicast in Networks Using NVO3",
draft-ghanwani-nvo3-mcast-issues-00, draft-ghanwani-nvo3-app-
mcast-framework-02, work in progress.
[VRF-LITE] Cisco, "Configuring VRF-lite", http://www.cisco.com
[VXLAN]
[RFC4301] Kent, S., "Security Architecture for the Internet
Protocol", rfc4301, December 2005
[RFC4364] Rosen, E. and Y. Rekhter, "BGP/MPLS IP Virtual Private
Networks (VPNs)", RFC 4364, February 2006.
[RFC7348] Mahalingam,M., Dutt, D., ific Multicast in etc "VXLAN: A
Framework for Overlaying Virtualized Layer 2 Networks over
Layer 3 Networks", draft-mahalingam-dutt-dcops-vxlan-06.txt, work
in progress. RFC7348 August 2014.
[VRF-LITE] Cisco, "Configuring VRF-lite", http://www.cisco.com
Contributors
Vinay Bannai
PayPal
2211 N. First St,
San Jose, CA 95131
Phone: +1-408-967-7784
Email: vbannai@paypal.com
Ram Krishnan
Brocade Communications
San Jose, CA 95134
Phone: +1-408-406-7890
Email: ramk@brocade.com
Acknowledgements
Authors like to thank Sue Hares, Young Lee, David Black, Pedro
Marques, Mike McBride, David McDysan, Randy Bush, Uma Chunduri, and
Eric Gray for the review, comments, and suggestions.
Authors' Addresses
Lucy Yong
Phone: +1-918-808-1918
Email: lucy.yong@huawei.com
Mehmet Toy
Comcast
1800 Bishops Gate Blvd.,
Mount Laurel, NJ 08054
Phone : +1-856-792-2801
E-mail : mehmet_toy@cable.comcast.com
Aldrin Isaac
Bloomberg
E-mail: aldrin.isaac@gmail.com
Vishwas Manral
Hewlett-Packard Corp.
3000 Hanover Street, Building 20C
Palo Alto, CA 95014
Phone: 650-857-5501
Email: vishwas.manral@hp.com
Linda Dunbar
Huawei Technologies,
5340 Legacy Dr.
Plano, TX 75025 US
Phone: +1-469-277-5840
Email: linda.dunbar@huawei.com