Internet Engineering Task Force Karthik Muthukrishnan
INTERNET-DRAFT Chandrasekar Kathirvelu
Tom Walsh
Expires January 2002 Lucent Technologies
Andrew Malis Fred Ammann
Vivace Networks, Inc. COMMCARE telecommunications
Jing Ming Xiao Junichi Sumimoto
China UNICOM NTT Information Sharing Platform Labs
July 2001
A Core MPLS IP VPN Architecture
<draft-ietf-ppvpn-rfc2917bis-00.txt>
1. Status of this Memo
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as Internet-
Drafts.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet- Drafts as reference
material or to cite them other than as "work in progress."
This draft is not a product of any working group and was written and
presented to the IETF well before the formation of any working group
related to Core VPNs.
The list of current Internet-Drafts can be accessed at
http://www.ietf.org/ietf/1id-abstracts.txt
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html.
Abstract This memo presents an approach for building core Virtual
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Private Network (VPN) services in a service provider's MPLS backbone.
This approach uses Multiprotocol Label Switching (MPLS) running in
the backbone to provide premium services in addition to best effort
services. The central vision is for the service provider to provide a
virtual router service to their customers. The keystones of this
architecture are ease of configuration, user security, network
security, dynamic neighbor discovery, scaling and the use of existing
routing protocols as they exist today without any modifications.
1.0. Acronyms
ARP Address Resolution Protocol
CE Customer Edge router
LSP Label Switched Path
PNA Private Network Administrator
SLA Service Level Agreement
SP Service Provider
PE Service Provider Edge Device
SPNA SP Network Administrator
VMA VPN Multicast Address
VPNID VPN Identifier
VR Virtual Router
VRC Virtual Router Console
P Provider Device
DSCP DiffServ Code Point
OUI Organizationally Unique Identifier
2.0. Introduction
This draft describes an approach for building IP VPN services out
of the backbone of the SP's network. Broadly speaking, two
possible approaches present themselves: the piggyback model and
the virtual router approach. The piggyback model is based on
overloading some semantic(s) of existing routing protocols to
carry reachability information. In this document, we focus on the
virtual router service.
The approach presented here does not depend on any modifications
of any existing routing protocols. This draft makes a concerted
effort to draw the line between the SP and the PNA: the SP owns
and manages layer 1 and layer 2 services while layer 3 services
belong to and are manageable by the PNA. By the provisioning of
fully logically independent routing domains, the PNA has been
given the flexibility to use private and unregistered addresses.
Due to the use of private LSPs and the use of VPNID encapsulation
using label stacks over shared LSPs, data security is not an
issue.
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The approach espoused in this draft differs from that described in
[Rosen1] in that no specific routing protocol has been overloaded
to carry VPN routes. [Rosen1] specifies a way to modify BGP to
carry VPN unicast routes across the SP's backbone. To carry
multicast routes, further architectural work will be necessary.
3.0. Virtual Routers
A virtual router is a collection of threads, either static or
dynamic, in a routing device, that provides routing and forwarding
services much like physical routers. A virtual router need not be
a separate operating system process (although it could be); it
simply has to provide the illusion that a dedicated router is
available to satisfy the needs of the network(s) to which it is
connected. A virtual router, like its physical counterpart, is an
element in a IP domain. The other routers in this domain could be
physical or virtual routers themselves. Given that the virtual
router connects to a specific (logically discrete) routing domain
and that a physical router can support multiple virtual routers,
it follows that a physical router supports multiple (logically
discreet) routing domains.
From the user (VPN customer) standpoint, it is imperative that the
virtual router be as equivalent to a physical router as possible.
In other words, with very minor and very few exceptions, the
virtual router should appear for all purposes (configuration,
management, monitoring and troubleshooting) like a dedicated
physical router. The main motivation behind this requirement is to
avoid upgrading or re-configuring the large installed base of
routers and to avoid retraining of network administrators.
The aspects of a router that a virtual router needs to emulate
are:
- Configuration of any combination of routing protocols
- Transport of Unicast and Multicast IP traffic with
differentiated or with absolute Qos.
- Monitoring of the network
- Troubleshooting.
Every VPN has a logically independent routing domain. This
enhances the SP's ability to offer a fully flexible virtual router
service that can fully serve the SP's customer without requiring
physical per-VPN routers. This means that the SP's "hardware"
investments, namely routers and links between them, can be re-used
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by multiple customers.
4.0. Objectives
4.1. Easy, scaleable configuration of VPN endpoints in the service
provider network. At most, one piece of configuration should be
necessary when a CE is added.
4.2. No use of SP resources that are globally unique and hard to
get such as IP addresses and subnets.
4.3. Dynamic discovery of VRs (Virtual Routers) in the SP's cloud.
This is an optional, but extremely valuable "keep it simple" goal.
4.4. Virtual Routers should be fully configurable and monitorable
by the VPN network administrator. This provides the PNA with the
flexibility to either configure the VPN themselves or outsource
configuration tasks to the SP.
4.5. Quality of data forwarding should be configurable on a VPN-
by-VPN basis. This should translate to continuous (but perhaps
discrete) grades of service. Some examples include best effort,
dedicated bandwidth, QOS, and policy based forwarding services.
4.6. Differentiated services should be configurable on a VPN-by-
VPN basis, perhaps based on LSPs set up for exclusive use for
forwarding data traffic in the VPN.
4.7. Security of internet routers extended to virtual routers.
This means that the virtual router's data forwarding and routing
functions should be as secure as a dedicated, private physical
router. There should be no unintended leak of information (user
data and reachability information) from one routing domain to
another.
4.8. Specific routing protocols should not be mandated between
virtual routers. This is critical to ensuring the VPN customer can
setup the network and policies as the customer sees fit. For
example, some protocols are strong in filtering, while others are
strong in traffic engineering. The VPN customer might want to
exploit both to achieve "best of breed" network quality.
4.9. No special extensions to existing routing protocols such as
BGP, RIP, OSPF, ISIS etc. This is critical to allowing the future
addition of other services such as NHRP and multicast. In
addition, as advances and addenda are made to existing protocols
(such as traffic engineering extensions to ISIS and OSPF), they
can be easily incorporated into the VPN implementation.
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5.0. Architectural Outline
5.1. Every VPN is assigned a VPNID which is unique within the SP's
network.i.e., local to the SP's network.
By definition there can be different VPNIDs for the same OUI in
different VPN clouds.
These different VPN Clouds are separated by one or more IP/MPLS
links.
This identifier unambiguously identifies the VPN with which a
packet or connection is associated. The VPNID of zero is reserved;
it is associated with and represents the public internet.
5.2. The VPN service is offered in the form of a Virtual Router
service. These VRs reside in the PE and are as such confined to
the edge of the SP's cloud. The VRs will use the SP's network for
data and control packet forwarding but are otherwise invisible
outside the PEs.
5.3. The "size" of the VR contracted to the VPN in a given PE is
expressed by the quantity of IP resources such as routing
interfaces, route filters, routing entries etc. This is entirely
under the control of the SP and provides the fine granularity that
the SP requires to offer virtually infinite grades of VR service
on a per-PE level. [Example: one PE may be the aggregating point
(say headquarters of the corporation) for a given VPN and a number
of other PE may be access points (branch offices). In this case,
the PE connected to the headquarters may be contracted to provide
a large VR while the PE connected to the branch offices may house
small, perhaps stub VRs]. This provision also allows the SP to
design the network with an end goal of distributing the load among
the routers in the network.
5.4. As per the traffic requirement we can incrementally add the
PEs.
5.5. One indicator of the VPN size is the number of PE in the SP's
network that have connections to CPE routers in that VPN. In this
respect, a VPN with many sites that need to be connected is a
"large" VPN whereas one with a few sites is a "small" VPN. Also,
it is conceivable that a VPN grows or shrinks in size over time.
VPNs may even merge due to corporate mergers, acquisitions and
partnering agreements. These changes are easy to accommodate in
this architecture, as globally unique IP resources do not have to
be dedicated or assigned to VPNs. The number of PE is not limited
by any artificial configuration limits.
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5.6. The SP owns and manages Layer 1 and Layer 2 entities. To be
specific, the SP controls physical switches or routers, physical
links, logical layer 2 connections (such as DLCI in Frame Relay
and VPI/VCI in ATM) and LSPs (and their assignment to specific
VPNs). In the context of VPNs, it is the SP's responsibility to
contract and assign layer 2 entities to specific VPNs.
5.7. Layer 3 entities belong to and are manageable by the PNA.
Examples of these entities include IP interfaces, choice of
dynamic routing protocols or static routes, and routing
interfaces. Note that although Layer 3 configuration logically
falls under the PNA's area of responsibility, it is not necessary
for the PNA to execute it. It is quite viable for the PNA to
outsource the IP administration of the virtual routers to the
Service Provider. Regardless of who assumes responsibility for
configuration and monitoring, this approach provides a full
routing domain view to the PNA and empowers the PNA to design the
network to achieve intranet, extranet and traffic engineering
goals.
5.8. The VPNs can be managed as if physical routers rather than
VRs were deployed. Therefore, management may be performed using
SNMP or other similar methods or directly at the VR console (VRC).
5.9. Industry-standard troubleshooting tools such as 'ping,'
'traceroute,' etc., are available in a routing domain exclusively
of dedicated physical routers. Therefore, monitoring and
troubleshooting may be performed using SNMP or similar methods,
but may also include the use of these standard tools. Again, the
VRC may be used for these purposes just like any physical router.
5.10. Since the VRC is visible to the user, router specific
security checks need to be put in place to make sure the VPN user
is allowed access to Layer 3 resources in that VPN only and is
disallowed from accessing physical resources in the router. Most
routers achieve this through the use of database views.
5.11. The VRC is available to the SP as well. If configuration and
monitoring has been outsourced to the SP, the SP may use the VRC
to accomplish these tasks as if it were the PNA.
5.12. The VRs in the PE form the VPN in the SP's network.
Together, they represent a virtual routing domain. They
dynamically discover each other by utilizing variety of technics.
5.13. If SPs network supports multicast then routing protocols
which uses multicast like OSPF, RIPV2 can be easily supported in
VPN.
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5.14. User data forwarding may be done in one of several ways:
5.14.1. An LSP with best-effort characteristics that all VPNS can
use.
5.14.2. An LSP dedicated to a VPN and traffic engineered by the
VPN customer.
5.14.3. A private LSP with differentiated characteristics.
5.14.4. Policy based forwarding on a dedicated L2 Virtual Circuit
The choice of the preferred method is negotiable between the SP and
the VPN customer, perhaps constituting part of the SLA between them.
This allows the SP to offer different grades of service to different
VPN customers.
Of course, hop-by-hop forwarding is also available to forward routing
packets and to forward user data packets during periods of LSP
establishment and failure.
5.15. This approach does not mandate that separate operating system
tasks for each of the routing protocols be run for each VR that the
PE houses. Specific implementations may be tailored to the particular
PE in use. Maintaining separate routing databases and forwarding
tables, one per VR, is one way to get the highest performance for a
given PE.
6.0. Scaleable Configuration
A typical VPN is expected to have 100s to 1000s of endpoints within
the SP cloud. Therefore, configuration should scale (at most)
linearly with the number of end points. To be specific, the
administrator should have to add a couple of configuration items when
a new customer site joins the set of VRs constituting a specific VPN.
Anything worse will make this task too daunting for the service
provider. In this architecture, all that the service provider needs
to allocate and configure is the ingress/egress physical link (e.g.
Frame Relay DLCI or ATM VPI/VCI) and the virtual connection between
the VR and the Service Provider Core.
7.0. VPN IP Domain Configuration
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151.0.0.1
################
# #
# ROUTER 'A' #
# #
################
# #
# #
# #
# #
############# ###############
# # # #
# ROUTER 'B'# # ROUTER 'C' #
# # # #
# # # #
############# ###############
152.0.0.2 153.0.0.3
Figure 1 'Physical Routing Domain'
The physical domain in the SP's network is shown in Figure.1. In this
network, physical routers A, B and C are connected together. Each of
the routers has a 'public' IP address assigned to it. These addresses
uniquely identify each of the routers in the SP's network.
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172.150.0/18 172.150.128/18
----------------------- ---------------------------|
| | |
| | 172.150.128.1
| ROUTER 'A' (151.0.0.1) | |---------|
| ############# | |Parts DB |
| ---#-----------# | /---------/
| OSPF | # # OSPF | /----------/
------------|# VR - A #|--------------
#-------|---#-|
#############10.0.0.1/24
|----|------------#-#---------------|-----|
|10.0.0.2/24# # |10.0.0.3/24
|------|-------| # # ---------|-------|
| ############### # |############### |
| # VR - B |# # # VR - C # |
|#-------------# ROUTER 'B'##|------------#----
(152.0.0.2)############### ############### (153.0.0.3)
| |
| |
------------------------- ROUTER 'C' |
172.150.64/18 V
Vendors Extranet
Figure 2 'Virtual Routing Domain'
Each Virtual Router is configurable by the PNA as though it were a
private physical router. Of course, the SP limits the resources that
this Virtual Router may consume on a PE-by-PE basis. Each VPN has a
number of physical connections (to CE routers) and a number of
logical connections (to the emulated LAN). The emulated LAN (shown
with IP addresses 10.0.0.x/24) provides the VPN Backbone connecting
the VRs in Figure 2. Each connection is IP-capable and can be
configured to utilize any combination of the standard routing
protocols and routing policies to achieve specific corporate network
goals.
To illustrate, in Figure 2, 3 VRs reside on 3 PE in VPN 1. Router 'A'
houses VR-A, router 'B' houses VR-B and router 'C' houses VR-C. VR-C
and VR-B have a physical connection to CE equipment, while VR-A has 2
physical connections. Each of the VRs has a fully IP-capable logical
connection to the emulated LAN. VR-A has the (physical) connections
to the headquarters of the company and runs OSPF over those
connections. Therefore, it can route packets to 172.150.0/18 and
172.150.128/18. VR-B runs RIP in the branch office (over the physical
connection) and uses RIP (over the logical connection) to export
172.150.64/18 to VR-A. VR-A advertises a default route to VR-B over
the logical connection. Vendors use VR-C as the extranet connection
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to connect to the parts database at 172.150.128.1. Hence, VR-C
advertises a default route to VR-A over the logical connection. VR-A
exports only 175.150.128.1 to VR-C. This keeps the rest of the
corporate network from a security problem.
The network administrator will configure the following:
7.1. OSPF connections to the 172.150.0/18 and 172.150.128/18 network
in VR-A.
7.2. RIP connections to VR-B and VR-C on VR-A.
7.3. Route policies on VR-A to advertise only the default route to
VR-B.
7.4. Route policies on VR-A to advertise only 172.150.128.1 to VR-C.
7.5. RIP on VR-B to VR-A.
7.6. RIP on VR-C to advertise a default route to VR-A.
8.0. Forwarding
As mentioned in the architectural outline, data forwarding may be
done in one of several ways. In all techniques except the Hop-by-Hop
technique for forwarding routing/control packets, the actual method
is configurable. At the high end, policy based forwarding for quick
service and at the other end best effort forwarding using public LSP
is used. The order of forwarding preference is as follows:
- Policy based forwarding.
- Optionally configured private LSP.
- Best-effort public LSP.
8.1 Private LSP
This LSP is optionally configured on a per-VPN basis. This LSP is
usually associated with non-zero bandwidth reservation and/or a
specific differentiated service or QOS class. If this LSP is
available, it is used for user data and for VPN private control data
forwarding.
8.2 Best Effort Public LSP
VPN data packets are forwarded using this LSP if a private LSP with
specified bandwidth and/or QOS characteristics is either not
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configured or not presently available. The LSP used is the one
destined for the egress router in VPN 0.(i.e., the reserved VPNID
designating the public Internet). The VPNID in the shim header is
used to de-multiplex data packets from various VPNs at the egress
router.
9.0. Differentiated Services
Configuring private LSPs for VPNs allows the SP to offer
differentiated services to paying customers. These private LSPs could
be associated with any available L2 QOS class or Diff-Serv
codepoints. In a VPN, multiple private LSPs with different service
classes could be configured with flow profiles for sorting the
packets among the LSPs. This feature, together with the ability to
size the virtual routers, allows the SP to offer truly differentiated
services to the VPN customer.
10.0. Security Considerations
10.1 Routing Security
The use of standard routing protocols such as OSPF and BGP in their
unmodified form means that all the encryption and security methods
(such as MD5 authentication of neighbors) are fully available in VRs.
Making sure that routes are not accidentally leaked from one VPN to
another is an implementation issue. One way to achieve this is to
maintain separate routing and forwarding databases.
10.2 Data Security
This allows the SP to assure the VPN customer that data packets in
one VPN never have the opportunity to wander into another. From a
routing standpoint, this could be achieved by maintaining separate
routing databases for each virtual router. From a data forwarding
standpoint, the use of label stacks in the case of shared LSPs
[Rosen2] [Callon] or the use of private LSPs guarantees data privacy.
Packet filters may also be configured to help ease the problem.
10.3 Configuration Security
Virtual routers appear as physical routers to the PNA. This means
that they may be configured by the PNA to achieve connectivity
between offices of a corporation. Obviously, the SP has to guarantee
that the PNA and the PNA's designees are the only ones who have
access to the VRs on the PE the private network has connections to.
Since the virtual router console is functionally equivalent to a
physical router, all of the authentication methods available on a
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physical console such as password, RADIUS, etc. are available to the
PNA.
10.4 Physical Network Security
When a PNA logs in to a PE to configure or monitor the VPN, the PNA
is logged into the VR for the VPN. The PNA has only layer 3
configuration and monitoring privileges for the VR. Specifically, the
PNA has no configuration privileges for the physical network. This
provides the guarantee to the SP that a VPN administrator will not be
able to inadvertently or otherwise adversely affect the SP's network.
11.0. Virtual Router Monitoring
All of the router monitoring features available on a physical router
are available on the virtual router. This includes utilities such as
"ping" and "traceroute". In addition, the ability to display private
routing tables, link state databases, etc. are available.
12.0. Performance Considerations
For the purposes of discussing performance and scaling issues,
today's routers can be split into two planes: the routing (control)
plane and the forwarding plane.
In looking at the routing plane, most modern-day routing protocols
use some form of optimized calculation methodologies to calculate the
shortest path(s) to end stations. For instance, OSPF and ISIS use the
Djikstra algorithm while BGP uses the "Decision Process". These
algorithms are based on parsing the routing database and computing
the best paths to end stations. The performance characteristics of
any of these algorithms is based on either topological
characteristics (ISIS and OSPF) or the number of ASs in the path to
the destinations (BGP). But it is important to note that the overhead
in setting up and beginning these calculations is very little for
most any modern day router. This is because, although we refer to
routing calculation input as "databases", these are memory resident
data structures.
Therefore, the following conclusions can be drawn:
1. Beginning a routing calculation for a routing domain is nothing
more than setting up some registers to point to the right database
objects.
2. Based on 1, the performance of a given algorithm is not
significantly worsened by the overhead required to set it up.
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3. Based on 2, it follows that, when a number of routing calculations
for a number of virtual routers has to be performed by a physical
router, the complexity of the resulting routing calculation is
nothing more than the sum of the complexities of the routing
calculations of the individual virtual routers.
4. Based on 3, it follows that whether an overlay model is used or a
virtual routing model is employed, the performance characteristics of
a router are dependent purely on its hardware capabilities and the
choice of data structures and algorithms.
To illustrate, let's say a physical router houses N VPNs, all running
some routing protocol say RP. Let's also suppose that the average
performance of RP's routing calculation algorithm is f(X,Y) where x
and y are parameters that determine performance of the algorithm for
that routing protocol. As an example, for Djikstra algorithm users
such as OSPF, X could be the number of nodes in the area while Y
could be the number of links. The performance of an arbitrary VPN n
is f (Xn, Yn). The performance of the (physical) router is the sum of
f(Xi, Yi) for all values of i in 0 <= i <= N. This conclusion is
independent of the chosen VPN approach (virtual router or overlay
model).
In the usual case, the forwarding plane has two inputs: the
forwarding table and the packet header. The main performance
parameter is the lookup algorithm. The very best performance one can
get for a IP routing table lookup is by organizing the table as some
form of a tree and use binary search methods to do the actual lookup.
The performance of this algorithm is O(log n).
Hence, as long as the virtual routers' routing tables are distinct
from each other, the lookup cost is constant for finding the routing
table and O(log n) to find the entry. This is no worse or different
from any router and no different from a router that employs overlay
techniques to deliver VPN services. However, when the overlay router
utilizes integration of multiple VPNs' routing tables, the
performance is O(log m*n) where 'm' is the number of VPNs that the
routing table holds routes for.
13.0. Some Applications
Some typical applications of PPVPN are illustrated here to assist
better understanding of the PPVPNs.
13.1. Example 1
World HQ wants to connect Regional HQs and small stationary
outlet/storage.
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( ) +-+
( ) ( )-----| |
( ) ( ) +-+ Regional Office 1
( C(HQ))-----( SP )
( ) ( ) +-+
( ) ( )------| | Regional office 2
( ) +-+
13.2. Example 2:
In the similar model as said above the SP's network may differ. More
than one SP will be involved in connecting the corporate user. In
that case we need a SLA between SPs for the service.
( ) ( ) +-+
( ) ( )-----(SP2)---| |
( ) ( ) ( ) +-+ Regional Office 1
( C(HQ))-----( SP1 )
( ) ( ) +-+
( ) ( )------| | Regional office 2
( ) +-+
We need a policy between two SP's VPN for exchange of routes. We
need VPN id conversion since the VPNs may have different ID in each
SP.
13.3. Example 3: When a Mobile user wants to join the VPN, the
connection can be made by an LSP tunnel or an IPSec tunnel to the
nearest VPN PE.
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( ) ( ) +-+
( ) ( )-----(SP2)---| |
( ) ( ) ( ) +-+ Regional Office 1 +-+
( C(HQ))-----( SP1 )----------//-----------------------| |
( ) ( ) +-+ +-+
( ) ( )------| | Regional office 2 Mobile user
( ) +-+
13.4. Hierarchical VPNs
+-+
+---| | Blue VPN
+-+ Blue VPN | +-+
| | ( ) Y ( ) +-+
+-+-- ( ) ( )-----(SP2)---| |
( ) Y ( ) (G) +-+ Red VPN
( SP2B )-----( SP1 )
( ) ( ) Y ( ) +-+
( ) ( )------(SP2)---| | Red VPN
+-+ | ( ) (F) +-+
| |-------+ | +-+
+-+ Red VPN +--------------| | Blue VPN
+-+
Y - Yellow VPN. Which SP2 gets from SP1.
SP2 bought Yellow VPN from SP1. SP2 has branch offices as SP2B, SP2G
and SP2F in different locations. SP2 also provides VPN services and
Red and Blue VPNs are SP2's customers.
SP2B CE for VPN Y towards SP1 will have the instance of Blue Red and
Yellow VPNs. Relation between Yellow VPN and Blue/Red VPN is
configured by policy. Yellow VPN provides separate transport for
Red/Blue VPNs, it does not participate in routing, which keeps all
the VPNs separate to each other, but still they can use the upper
level VPN for transport. In this example Client of SP2B Red VPN can
peer with RedVPN in SP2G. SP2G will peer with SP2B in Yellow VPN.
Data from RedVPN in SP2B will use Yellow VPN link from SP2B through
SP1 to SP2G. Data from BlueVPN will also use the same path or same
LSP. In SP2G it will be demuxed to reach Red/Blue VPNs. Here
YellowVPN acts like a LSP tunnel to Red/Blue VPNs.
14.0. References
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[Callon] Callon R., et al, "A framework for Multiprotocol Label
Switching", draft-ietf-mpls-framework-05.txt.
[Fox] Fox B., et al, "Virtual Private Networks Identifier", RFC 2685.
[Meyer] Meyer D., "Administratively Scoped IP Multicast", RFC 2365.
[Rosen1] Rosen, E., et al. draft-rosen-rfc2547bis-02.txt
[Rosen2] Rosen E., et al, "Multiprotocol Label Switching
Architecture", draft-ietf-mpls-arch-06.txt.
[muthuk] K.Muthukrishnan, A.Malis "A Core MPLS IP VPN Architecture",
RFC 2917 September 2000.
[VPN-FRAME] M.Suzuki, J.Sumimoto, "A Framework for Network-based
VPNs", <draft-suzuki-nbvpn-framework-01.txt>, October 2000.
15. Authors' addresses
Karthik Muthukrishnan
Lucent Technologies
1 Robbins Road
Phone: (978) 952-1368
Westford, MA 01886
Email: mkarthik@lucent.com
Andrew Malis
Vivace Networks, Inc.
2730 Orchard Parkway
San Jose, CA 95134
Phone: (408) 383-7223
EMail: Andy.Malis@vivacenetworks.com
Chandrasekar Kathirvelu
Lucent Technologies
1 Robbins Road
Westford, MA 01886
Phone: (978) 952-7116
EMail: ck32@lucent.com
Tom Walsh
Lucent Technologies
10 Lyberty Way
Westford, MA 01886
Phone: (978) 392-2311
EMail: tdwalsh@lucent.com
Muthukrishnan et al. Expires January 2002 [Page 16]
INTERNET-DRAFT Core VPNs July 2001
Fred Ammann
COMMCARE Telecommunications
Turmstrasse 8
CH-8952 Schlieren
Switzerland
Phone: +41 1 738 61 11
Email: fa@commcare.ch
Jing Ming Xiao
China UNICOM
Data & Fixed Communication Department
6/F Office Tower 3
Henderson Center
Beijing, China
Email: unicomnet@bj.cnuninet.net
Junichi Sumimoto
NTT Information Sharing Platform Labs
3-9-11, Midori-cho
Musashino-shi, Tokyo 180-8585
Japan
Email: sumimoto.junichi@lab.ntt.co.jp
Muthukrishnan et al. Expires January 2002 [Page 17]