Framework for DC Network Virtualization
draft-lasserre-nvo3-framework-00
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| Authors | Marc Lasserre , Florin Balus , Thomas Morin | ||
| Last updated | 2012-03-05 | ||
| Replaced by | draft-ietf-nvo3-framework, RFC 7365 | ||
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draft-lasserre-nvo3-framework-00
Internet Engineering Task Force Marc Lasserre
Internet Draft Florin Balus
Intended status: Informational Alcatel-Lucent
Expires: September 2012
Thomas Morin
France Telecom Orange
March 5, 2012
Framework for DC Network Virtualization
draft-lasserre-nvo3-framework-00.txt
Status of this Memo
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carefully, as they describe your rights and restrictions with
respect to this document.
Abstract
Several IETF drafts relate to the use of overlay networks to support
large scale virtual data centers. This draft provides a framework
for Network Virtualization over L3 (NVO3) and is intended to help
plan a set of work items in order to provide a complete solution
set. It defines a logical view of the main components with the
intention of streamlining the terminology and focusing the solution
set.
Table of Contents
1. Introduction...................................................3
1.1. Conventions used in this document.........................4
1.2. General terminology.......................................4
1.3. DC network architecture...................................4
1.4. Tenant networking view....................................6
2. Reference Models...............................................7
2.1. Generic Reference Model...................................7
2.2. NVE Reference Model.......................................9
2.3. NVE Service Types........................................10
2.3.1. L2 NVE providing Ethernet LAN-like service..........10
2.3.2. L3 NVE providing IP/VRF-like service................10
3. Functional components.........................................10
3.1. Generic service virtualization components................10
3.1.1. Virtual Access Points (VAPs)........................11
3.1.2. Tenant Instance.....................................11
3.1.3. Overlay Modules and Tenant ID.......................12
3.1.4. Tunnel Overlays and Encapsulation options...........12
3.1.5. Use of Control Plane Protocols......................13
3.2. Service Overlay Topologies...............................13
4. Key aspects of overlay networks...............................13
4.1. Pros & Cons..............................................13
4.2. Overlay issues to consider...............................14
4.2.1. End System to Overlay Network Mapping...............14
4.2.2. Address to tunnel mapping...........................15
4.2.3. Data plane vs Control plane driven..................15
4.2.4. Coordination between data plane and control plane...16
4.2.5. Multicast Handling..................................16
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4.2.6. Path MTU............................................16
4.2.7. NVE location trade-offs.............................17
4.2.8. Interaction between network overlays and underlays..18
5. Security Considerations.......................................18
6. IANA Considerations...........................................19
7. References....................................................19
7.1. Normative References.....................................19
7.2. Informative References...................................19
8. Acknowledgments...............................................20
1. Introduction
This document provides a framework for Data Center Network
Virtualization over L3 tunnels. This framework is intended to aid in
standardizing protocols and mechanisms to support large scale
network virtualization for data centers.
Several IETF drafts relate to the use of overlay networks for data
centers.
[NVOPS] defines the rationale for using overlay networks in order to
build large data center networks. The use of virtualization leads to
a very large number of communication domains and end systems to cope
with. Existing virtual network models used for data center networks
have known limitations, specifically in the context of multiple
tenants, that have also been described in various sections of
[VXLAN], [NVGRE], and [DCVPN]. These issues can be summarized as:
o Limited VLAN space
o FIB explosion due to handling of large number of MACs/IP
addresses
o Spanning Tree limitations
o Excessive ARP handling
o Broadcast storms
o Inefficient Broadcast/Multicast handling
o Limited mobility/portability support
o Lack of service auto-discovery
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[VXLAN], [NVGRE], [STT] and [DCVPN] describe the use of overlay
techniques that address some of these issues.
[OVCPREQ] describes the requirements for a control plane protocol
required by overlay border nodes to exchange overlay mappings.
This document provides reference models and functional components of
data center overlay networks as well as a discussion of technical
issues that have to be addressed in the design of standards and
mechanisms for large scale data centers.
1.1. Conventions used in this document
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].
In this document, these words will appear with that interpretation
only when in ALL CAPS. Lower case uses of these words are not to be
interpreted as carrying RFC-2119 significance.
1.2. General terminology
Some general terminology is defined here. Terminology specific to
this memo is introduced as needed in later sections.
DC: Data Center
ELAN: MEF ELAN, multipoint to multipoint Ethernet service
EVPN: Ethernet VPN as defined in [EVPN]
1.3. DC network architecture
A generic architecture for Data Centers is depicted in Figure 1:
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,---------.
,' `.
( IP/MPLS WAN )
`. ,'
`-+------+'
+--+--+ +-+---+
|DC GW|+-+|DC GW|
+-+---+ +-----+
| /
.--. .--.
( ' '.--.
.-.' Intra-DC '
( network )
( .'-'
'--'._.'. )\ \
/ / '--' \ \
/ / | | \ \
+---+--+ +-`.+--+ +--+----+
| ToR | | ToR | | ToR |
+-+--`.+ +-+-`.-+ +-+--+--+
.' \ .' \ .' `.
__/_ _i./ i./_ _\__
'----' '----' '----' '----'
: ED : : ED : : ED : : ED :
'----' '----' '----' '----'
Figure 1 : A Generic Architecture for Data Centers
An example of multi-tier DC network architecture is presented in
this figure. A cloud network is composed of intra-Data Center (DC)
networks and network services, and, inter-DC network and network
connectivity services. Depending upon the scale, DC distribution,
operations model, Capex and Opex aspects, DC networking elements can
act as strict L2 switches and/or provide IP routing capabilities,
including also service virtualization.
In some DC architectures, it is possible that some tier layers
provide L2 and/or L3 services, are collapsed, and that Internet
connectivity, inter-DC connectivity and VPN support are handled by a
smaller number of nodes. Nevertheless, one can assume that the
functional blocks fit with the architecture above.
The following components can be present in a DC:
o End Device (ED): a DC resource to which the networking service
is provided. ED may be a compute resource (server or server
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blade), storage component or a network appliance (firewall,
load-balancer, IPsec gateway). Alternatively, the End Device
may include software based networking functions used to
interconnect multiple IP hosts. An example of soft networking
is the virtual switch in the server blades, used to
interconnect multiple virtual machines (VMs). ED may be single
or multi-homed to the Top of Rack switches (ToRs).
o Top of Rack (ToR): Hardware-based Ethernet switch aggregating
all Ethernet links from the End Devices in a rack representing
the entry point in the physical DC network for the hosts. ToRs
may also provide routing functionality, virtual IP network
connectivity, or Layer2 tunneling over IP for instance. ToRs
are usually multi-homed to switches in the Intra-DC network.
Other deployment scenarios may use an EoR (End of Row) switch
to provide similar function as a ToR.
o Intra-DC Network: High capacity network composed of core
switches aggregating multiple ToRs. Core switches are usually
Ethernet switches but can also support routing capabilities.
o DC GW: Gateway to the outside world providing DC Interconnect
and connectivity to Internet and VPN customers. In the current
DC network model, this may be simply a Router connected to the
Internet and/or an IPVPN/L2VPN PE. Some network implementations
may dedicate DC GWs for different connectivity types (e.g., a
DC GW for Internet, and another for VPN).
We use throughout this document the term "End System" to define an
end system of a particular tenant, which can be for instance a
virtual machine (VM), a non-virtualized server, or a non-virtualized
network appliance. One or more End Systems can be part of an ED.
1.4. Tenant networking view
The DC network architecture is used to provide L2 and/or L3 service
connectivity to each tenant. An example is depicted in Figure 2:
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+----- L3 Infrastructure ----+
| |
,--+-'. ;--+--.
..... Rtr1 )...... . Rtr2 )
| '-----' | '-----'
| Tenant1 |LAN12 Tenant1|
|LAN11 ....|........ |LAN13
'':'''''''':' | | '':'''''''':'
,'. ,'. ,+. ,+. ,'. ,'.
(VM )....(VM ) (VM )... (VM ) (VM )....(VM )
`-' `-' `-' `-' `-' `-'
Figure 2 : Logical Service connectivity for a single tenant
In this example one or more L3 contexts and one or more LANs (e.g.,
one per Application) running on DC switches are assigned for DC
tenant 1.
For a multi-tenant DC, a virtualized version of this type of service
connectivity needs to be provided for each tenant by the Network
Virtualization solution.
2. Reference Models
2.1. Generic Reference Model
The following diagram shows a DC reference model for network
virtualization using Layer3 overlays where edge devices provide a
logical interconnect between end systems that belong to specific
tenant network.
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+--------+ +--------+
+ End +--+ +---| End |
+ System + | | | System |
+--------+ | ................... | +--------+
| +-+--+ +--+-+ |
| | NV | | NV | |
+--|Edge| |Edge|--+
+-+--+ +--+-+
/ . L3 Overlay . \
+--------+ / . Network . \ +--------+
+ End +--+ . . +----| End |
+ System + . +----+ . | System |
+--------+ .....| NV |........ +--------+
|Edge|
+----+
|
|
+--------+
| End |
| System |
+--------+
Figure 3 : Generic reference model for DC network virtualization
over a Layer3 infrastructure
An End System attaches to a Network Virtualization Edge (NVE) node,
either directly or via a switched network (typically Ethernet).
Examples of DC End Systems are host machines, including Virtual
Machines, Network Appliances or Storage Systems.
The NVE implements network virtualization functions that allow for
L2 and/or L3 tenant separation and for hiding tenant addressing
information (MAC and IP addresses), tenant-related control plane
activity and service contexts from the Routed Backbone nodes.
Core nodes utilize L3 techniques to interconnect NVE nodes in
support of the overlay network. These devices perform forwarding
based on outer L3 tunnel header, and generally do not maintain per
tenant-service state albeit some applications (e.g., multicast) may
require control plane or forwarding plane information that pertain
to a tenant, group of tenants, tenant service or a set of services
that belong to one or more tunnels. When such tenant or tenant-
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service related information is maintained in the core, overlay
virtualization provides knobs to control the magnitude of that
information.
2.2. NVE Reference Model
The NVE is composed of a tenant service instance that end systems
interface with and an overlay module that provides tunneling overlay
functions (e.g. encapsulation/decapsulation of tenant traffic
from/to the tenant forwarding instance, tenant identification and
mapping, etc), as described in figure 4:
+------- L3 Network ------+
| |
| |
+------------+--------+ +--------+------------+
| +----------+------+ | | +------+----------+ |
| | Overlay Module | | | | Overlay Module | |
| +--------+--------+ | | +--------+--------+ |
| | | | | |
| NVE1 | | | | NVE2 |
| +-------+-------+ | | +-------+-------+ |
| |Tenant Instance| | | |Tenant Instance| |
| +-+-----------+-+ | | +-+-----------+-+ |
| | | | | | | |
+----+-----------+----+ +----+-----------+----+
| | | |
-------+-----------+-----------------+-----------+-------
| | Tenant | |
| | Service IF | |
End Systems End Systems
Figure 4 : Generic reference model for NV Edge
Note that some NVE functions (e.g. data plane and control plane
functions) may reside in one device or they may be distributed
between multiple devices.
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2.3. NVE Service Types
NVE components may be used to provide different types of virtualized
service connectivity. This section defines the service types and
associated attributes
2.3.1. L2 NVE providing Ethernet LAN-like service
L2 NVE implements Ethernet LAN emulation (ELAN), an Ethernet based
multipoint service where the End Systems appear to be interconnected
by a LAN environment over a set of L3 tunnels. It provides per
tenant virtual switching instance with MAC addressing isolation and
L3 tunnel encapsulation across the core.
2.3.2. L3 NVE providing IP/VRF-like service
Virtualized IP routing and forwarding is similar from a service
definition perspective with IETF IP VPN (e.g., BGP/MPLS IPVPN and
IPsec VPNs). It provides per tenant routing instance with addressing
isolation and L3 tunnel encapsulation across the core.
3. Functional components
This section breaks down the Network Virtualization architecture
into functional components to make it easier to discuss solution
options for different modules.
This version of the document gives an overview of generic functional
components that are shared between L2 and L3 service types. Details
specific for each service type will be added in future revisions.
3.1. Generic service virtualization components
A Network Virtualization solution is built around a number of
functional components as depicted in Figure 5:
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+------- L3 Network ------+
| |
| Tunnel Overlay |
+------------+--------+ +--------+------------+
| +----------+------+ | | +------+----------+ |
| | Overlay Module | | | | Overlay Module | |
| +--------+--------+ | | +--------+--------+ |
| |Tenant ID | | |Tenant ID |
| | (TNI) | | | (TNI) |
| +-------+-------+ | | +-------+-------+ |
| |Tenant Instance| | | |Tenant Instance| |
NVE2 | +-+-----------+-+ | | +-+-----------+-+ | NVE1
| | VAPs | | | | VAPs | |
+----+-----------+----+ +----+-----------+----+
| | | |
-------+-----------+-----------------+-----------+-------
| | Tenant | |
| | Service IF | |
End Systems End Systems
Figure 5 : Generic reference model for NV Edge
3.1.1. Virtual Access Points (VAPs)
End Systems are connected to the Tenant Instance through Virtual
Access Points (VAPs). The VAPs can be in reality physical ports on a
ToR or virtual ports identified through logical interface
identifiers (VLANs, internal VSwitch Interface ID leading to a VM).
3.1.2. Tenant Instance
The Tenant Instance represents a set of configuration attributes
defining access and tunnel policies and (L2 and/or L3) forwarding
functions.
Per tenant FIB tables and control plane protocol instances are used
to maintain separate private contexts between tenants. Hence tenants
are free to use their own addressing schemes without concerns about
address overlapping with other tenants.
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3.1.3. Overlay Modules and Tenant ID
The Overlay module provides tunneling overlay functions: tunnel
initiation/termination, encapsulation/decapsulation of frames from
VAPs/L3 Backbone and may provide for transit forwarding of IP
traffic (e.g., transparent tunnel forwarding).
In a multi-tenant context, the tunnel aggregates frames from/to
different Tenant Instances. Tenant identification and traffic
demultiplexing are based on the Tenant Identifier (TNI).
At least two possible approaches for TNI should be considered:
o One ID per Tenant: A globally unique (on a per-DC
administrative domain) Tenant ID is used to identify the
related Tenant instances. An example of this approach is the
use of IEEE VLAN or ISID tags to provide virtual L2 domains.
o One ID per Tenant Instance (TNI): A per-tenant local ID is
automatically generated by the egress NVE and usually
distributed by a control plane protocol to all the related
NVEs. An example of this approach is the use of per VRF MPLS
labels in IP VPN [RFC4364].
o One ID per VAP: A per-VAP local ID is assigned and usually
distributed by a control plane protocol. An example of this
approach is the use of per CE-PE MPLS labels in IP VPN
[RFC4364].
Note that when using one ID per TNI or VAP, an additional global
identifier may be used by the control plane to identify the Tenant
context.
3.1.4. Tunnel Overlays and Encapsulation options
Once the TNI is added to the frame an IP Tunnel encapsulation is
used to transport the frame to the destination NVE. The backbone
devices do not usually keep any per service state, simply forwarding
the frames based on the outer tunnel header.
Different IP tunneling options (GRE/L2TP/IPSec) are already
available for both Ethernet and IP formats. A UDP/IP option is
described in [VXLAN].
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3.1.5. Use of Control Plane Protocols
A set of control plane components may be used to provide certain
functions related to auto-provisioning, route advertisement,
efficient BUM handling, or ARP reduction for instance, as discussed
in section 4.2.
Further details will be provided in a subsequent revision of this
document.
3.2. Service Overlay Topologies
A number of service topologies may be used to optimize the service
connectivity and to address NVE performance limitations.
The topology described in Figure 3 suggests the use of a tunnel mesh
between the NVEs where each tenant instance is one hop away from a
service processing perspective. Partial mesh topologies and an NVE
hierarchy may be used where certain NVEs may act as service transit
points.
4. Key aspects of overlay networks
4.1. Pros & Cons
An overlay network is a layer of virtual network topology on top of
the physical network.
Overlay networks offer the following key advantages:
o Tunnel state management is handled at the edge of the network.
Intermediate transport nodes are unaware of such state,
provided that flood containment or multicast capabilities on a
per-tenant basis are not required from the core network
o Tunnels are used to aggregate traffic and hence offer the
advantage of minimizing the amount of forwarding state required
within the underlay network
o Decoupling of the overlay addresses (MAC and IP) used by VMs
from the underlay network. This offers a clear separation
between addresses used within the overlay and the underlay
networks and it enables the use of overlapping addresses spaces
by end systems
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o Support of a large number of virtual network identifiers
Overlay networks also create several challenges:
o Overlay networks have no controls of underlay networks and lack
critical network information
o Overlays typically probe the network to measure link
properties, such as available bandwidth or packet loss
rate. It is difficult to accurately evaluate network
properties. It might be preferable for the underlay
network to expose usage and performance information.
o Miscommunication between overlay and underlay networks can lead
to an inefficient usage of network resources.
o Fairness of resource sharing and collaboration among end-nodes
in overlay networks are two critical issues
o When multiple overlays co-exist on top of a common underlay
network, the lack of communication between overlays can lead to
performance issues.
o Overlaid traffic may not traverse firewalls and NAT devices.
o Multicast service scalability. Multicast support may be
required in the overlay network to address for each tenant
flood containment or efficient multicast handling.
4.2. Overlay issues to consider
4.2.1. End System to Overlay Network Mapping
NVEs must be able to select the appropriate Tenant Instance for each
End System. This is based on state information that is often
distributed from external entities. For example, in a VM
environment, this information is provided by compute management
systems, since these are the only entities that have visibility on
which VM belongs to which tenant.
A standard mechanism for communicating this information between End
Systems and the network is required. Note, that depending on the
implementation this control interface can be between compute
management and a virtual switch or between compute management and/or
End Systems and a ToR switch.
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In either case the protocol must provide appropriate security and
authentication mechanisms to verify that End System information is
not spoofed or altered. This is one of the most critical aspects for
providing integrity and tenant isolation in the system.
4.2.2. Address to tunnel mapping
As traffic reaches an ingress NVE, a lookup is performed to
determine which tunnel the packet needs to be sent to. It is then
encapsulated with a tunnel header containing the destination address
of the egress overlay node. Intermediate nodes (between the ingress
and egress NVEs) switch or route traffic based upon the outer
destination address.
One key step in this process consists of mapping a final destination
address to the proper tunnel. NVEs are responsible for maintaining
such mappings in their lookup tables.
Several ways of populating these lookup tables are possible: data
plane driven, control plane driven or management plane driven.
Destination addresses can be dynamically learned as would occur in
standard bridges, or they can be populated by a control plane
protocol or a network management system.
4.2.3. Data plane vs Control plane driven
Dynamic (data plane) learning implies that flooding of unknown
destinations be supported and hence implies that broadcast and/or
multicast be supported. Multicasting in the core network for dynamic
learning can lead to significant scalability limitations. Specific
forwarding rules must be enforced to prevent loops from happening.
This can be achieved using a spanning tree protocol or a shortest
path tree, or using a split-horizon mesh.
A control plane protocol can distribute this information instead. As
an example, [EVPN] describes a procedure to distribute the VM MACs
and build forwarding entries in each Tenant Instance. Alternative
control plane protocols and/or options are applicable.
It should be noted that the amount of state to be distributed is a
function of the number of virtual machines. Different forms of
caching can also be utilized to minimize state distribution between
the various elements.
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4.2.4. Coordination between data plane and control plane
Often a combination of data plane and control based learning is
necessary. Learning is applied towards end-user facing ports whereas
distribution is used on the tunnel ports. Coordination between the
learning engine and the control protocol is needed such that when a
new address gets learned or an old address is removed, it triggers
the local control plane to distribute this information to its peers.
4.2.5. Handling Broadcast, Unknown Unicast and Multicast (BUM) traffic
There are two techniques to support packet replication needed for
broadcast, unknown unicast and multicast:
o Ingress replication
o Use of core multicast trees
There is a bandwidth vs state trade-off between the two approaches.
Depending upon the degree of replication required (i.e. the number
of hosts per group) and the amount of multicast state to maintain,
trading bandwidth for state is of consideration.
When the number of hosts per group is large, the use of core
multicast trees may be more appropriate. When the number of hosts is
small (e.g. 2-3), ingress replication may not be an issue.
Depending upon the size of the data center network and hence the
number of (S,G) entries, but also the duration of multicast flows,
the use of core multicast trees can be a challenge.
When flows are well known, it is possible to pre-provision such
multicast trees. However, it is often difficult to predict
application flows ahead of time, and hence programming of (S,G)
entries for short-lived flows could be impractical.
A possible trade-off is to use in the core shared multicast trees as
opposed to dedicated multicast trees.
4.2.6. Path MTU
When using overlay tunneling, an outer header is added to the
original frame. This can cause the MTU of the path to the egress
tunnel endpoint to be exceeded.
In this section, we will only consider the case of an IP overlay.
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It is usually not desirable to rely on IP fragmentation for
performance reasons. Ideally, the interface MTU as seen by an end
system is adjusted such that no fragmentation is needed. TCP will
adjust its maximum segment size accordingly.
It is possible for the MTU to be configured manually or to be
discovered dynamically. Various Path MTU discovery techniques exist
in order to determine the proper MTU size to use:
o Classical ICMP-based MTU Path Discovery [RFC1191] [RFC1981]
o End systems rely on ICMP messages to discover the MTU of
the end-to-end path to its destination. This method is not
always possible, such as when traversing middle boxes
(e.g. firewalls) which disable ICMP for security reasons
o Extended MTU Path Discovery techniques such as defined in
[RFC4821]
It is also possible to rely on the overlay layer to perform
segmentation and reassembly operations without relying on the end
systems to know about the end-to-end MTU. The assumption is that
some hardware assist is available on the NVE node to perform such
SAR operations. Such a mechanism is described in [STT]. However,
fragmentation by the overlay layer can lead to performance and
congestion issues due to TCP dynamics and might require new
congestion avoidance mechanisms from then underlay network [FLOYD].
Finally, the underlay network may be designed in such a way that the
MTU can accommodate the extra tunnel overhead.
4.2.7. NVE location trade-offs
In the case of DC traffic, traffic originated from a VM is native
Ethernet traffic. This traffic can be switched by a local VM switch
or ToR switch and then by a DC gateway. The NVE function can be
embedded within any of these elements.
There are several criteria to consider when deciding where the NVE
processing boundary happens:
o Processing and memory requirements
o Datapath (e.g. lookups, filtering,
encapsulation/decapsulation)
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o Control plane processing (e.g. routing, signaling, OAM)
o FIB/RIB size
o Multicast support
o Routing protocols
o Packet replication capability
o Fragmentation support
o QoS transparency
o Resiliency
4.2.8. Interaction between network overlays and underlays
When multiple overlays co-exist on top of a common underlay network,
this can cause some performance issues. These overlays have
partially overlapping paths and nodes.
Each overlay is selfish by nature in that it sends traffic so as to
optimize its own performance without considering the impact on other
overlays, unless the underlay tunnels are traffic engineered on a
per overlay basis so as to avoid sharing underlay resources.
Better visibility between overlays and underlays can be achieved by
providing mechanisms to exchange information about:
o Performance metrics (throughput, delay, loss, jitter)
o Cost metrics
5. Security Considerations
The tenant to overlay mapping function can introduce significant
security risks if appropriate protocols are not used that can
support mutual authentication.
No other new security issues are introduced beyond those described
already in the related L2VPN and L3VPN RFCs.
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6. IANA Considerations
IANA does not need to take any action for this draft.
7. References
7.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
7.2. Informative References
[NVOPS] Narten, T. et al, "Problem Statement : Overlays for Network
Virtualization", draft-narten-nvo3-overlay-problem-
statement (work in progress)
[OVCPREQ] Kreeger, L. et al, "Network Virtualization Overlay Control
Protocol Requirements", draft-kreeger-nvo3-overlay-cp
(work in progress)
[DCVPN] Bitar, N. et al, "Cloud Networking: Framework and VPN
Applicability", draft-bitar-datacenter-vpn-applicability
(work in progress)
[EVPN] Raggarwa, R. et al. "BGP MPLS based Ethernet VPN", draft-
ietf-l2vpn-evpn (work in progress)
[NVGRE] Sridhavan, M. et al, "NVGRE: Network Virtualization using
Generic Routing Encapsulation", draft-sridharan-
virtualization-nvgre (work in progress)
[STT] Davie, B., "A Stateless Transport Tunneling Protocol for
Network Virtualization", draft-davie-stt (work in
progress)
[VXLAN] Mahalingam, M. et al, "VXLAN: A Framework for Overlaying
Virtualized Layer 2 Networks over Layer 3 Networks",
draft-mahalingam-dutt-dcops-vxlan (work in progress)
[FLOYD] Sally Floyd, Allyn Romanow, "Dynamics of TCP Traffic over
ATM Networks", IEEE JSAC, V. 13 N. 4, May 1995
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[RFC4364] Rosen, E. and Y. Rekhter, "BGP/MPLS IP Virtual Private
Networks (VPNs)", RFC 4364, February 2006.
[RFC1191] Mogul, J. "Path MTU Discovery", RFC1191, November 1990
[RFC1981] McCann, J. et al, "Path MTU Discovery for IPv6", RFC1981,
August 1996
[RFC4821] Mathis, M. et al, "Packetization Layer Path MTU
Discovery", RFC4821, March 2007
8. Acknowledgments
In addition to the authors the following people have contributed to
this document:
Nabil Bitar, Verizon
Dimitrios Stiliadis, Rotem Salomonovitch, Alcatel-Lucent
This document was prepared using 2-Word-v2.0.template.dot.
Authors' Addresses
Marc Lasserre
Alcatel-Lucent
Email: marc.lasserre@alcatel-lucent.com
Florin Balus
Alcatel-Lucent
777 E. Middlefield Road
Mountain View, CA, USA 94043
Email: florin.balus@alcatel-lucent.com
Thomas Morin
France Telecom Orange
Email: thomas.morin@orange.com
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