PPVPN Working Group Waldemar Augustyn
Internet Draft
Document: draft-augustyn-ppvpn-l2vpn-requirements-00.txt Giles Heron
Category: Informational PacketExchange Ltd
June 2002 Vach Kompella
Expires: December 2002 TiMetra Networks
Marc Lasserre
Riverstone Networks
Pascal Menezes
Terabeam
Hamid Ould-Brahim
Nortel Networks
Tissa Senevirathne
Requirements for Layer 2 Virtual Private Network Services (L2VPN)
Status of this Memo
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026 [1].
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-
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Internet-Drafts are draft documents valid for a maximum of six
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For potential updates to the above required-text see:
http://www.ietf.org/ietf/1id-guidelines.txt
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Summary for Sub-IP related Internet Drafts
RELATED DOCUMENTS:
See references.
WHERE DOES IT FIT IN THE PICTURE OF THE SUB-IP WORK
This ID is intended for the PPVPN WG.
WHY IS IT TARGETED AT THIS WG(s)
PPVPN deals with provider provisioned VPNs. This document describes
requirements for L2 Virtual Private Network Services.
JUSTIFICATION
This document represents the evolution of draft-ietf-ppvpn-vpls-
requirements-00.txt to include requirements for Virtual Private Wire
Services.
1 Abstract
This draft describes service requirements for L2 Virtual Private
Networks. It covers non-broadcast point to point and point to
multipoint VPNs referred to as Virtual Private Wire Service (VPWS),
as well as broadcast domain multipoint to multipoint VPNs referred
to as Virtual Private LAN Service (VPLS). L2VPNs are a class of
Provider Provisioned Virtual Private Network [2].
This draft is intended to supersede draft-ietf-ppvpn-vpls-
requirements-00.txt [3].
2 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 [4].
3 Definitions
A network service offered by Service Providers where packets are
forwarded based on layer 2 information (such as FR, ATM, or MAC)
and/or on the basis of the incoming link. The term is also used,
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when clear from the context, to refer to a particular instance of
L2VPN service.
3.2 L2VPN System
A collection of communication equipment, related protocols, and
configuration elements that implements L2VPN Services.
Virtual Switching Instance. A virtual layer 2 forwarding entity that
is closed to a L2VPN membership. VSI forwarding can be based on MAC
addresses, VLAN tags, policies, topologies, filters, QoS parameters,
and other relevant information on a per L2VPN basis.
Virtual Private WAN Service, a case of L2VPN implementing a non-
broadcast point to point, or point to multipoint VPN. The term is
also used, when clear from the context, to refer to a particular
instance of VPWS service.
Virtual Private LAN Service, a case of L2VPN service distinguished
by the support of L2 broadcast. The term is also used, when clear
from the context, to refer to a particular instance of VPLS service.
A VPLS service allows the connection of multiple sites in a single
bridged domain over a provider managed IP or MPLS network. All
customer sites in the VPLS appear to be on the same LAN regardless
of their location.
3.6 VPLS Domain
A Layer 2 VPN that is composed of a community of interest of L2 MAC
addresses and VLANs. Each VPLS Domain MAY have multiple VLANs in it.
A customer VLAN identification using some scheme such as IEEE 802.1Q
tags, port configuration or any other means. A VPLS service can be
extended to recognize customer VLANs as specified in 6.1 .
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3.8 VLAN Flooding Scope (VLAN Broadcast Domain)
The scope of flooding for a given VLAN. In a VPLS service, a VLAN
flooding scope is identical to the flooding scope of the VPLS it is
part of. If a VPLS service is extended to recognize customer VLANs,
the VLAN flooding scope is limited to the broadcast domain of each
recognized VLAN.
4 Introduction
This document describes the service requirements for Layer 2 Virtual
Private Networks.
4.1 The context of provider provisioned service
The context of provider provisioned VPNs is an important factor in
the structure and scope of the requirements. This context brings
attention to the fact that there are two entities involved in
operation of such services, the Provider and the Customer. The
Provider engages in a binding agreement with the Customer as to the
behavior of the service in normal situation as well as exceptional
situations. Such agreement is known as Service Level Agreement
(SLA).
A proper design of L2 VPNs aids formulation of SLAs in that it
provides means for proper separation between CE/PE, allows proper
execution of the SLA offer, and supports flexible and rich set of
capabilities.
4.2 L2VPN taxonomy
The requirements distinguish two major L2VPNs models, a Virtual
Private Wire Service (VPWS), and a Virtual Private LAN Service
(VPLS). The VPWS model is simpler than VPLS and its requirements are
a subset of those for VPLS.
The document generally refers to L2VPN requirements which are
applicable to both VPWS and VPLS. The additional requirements for
VPLS are clearly stated as such.
4.2.1 Virtual Private Wire Service
By far the most widely deployed are point to point VPNs. A point to
point VPN behaves like a circuit terminated by a Customer Equipment
(CE) at each end. This type of L2VPN service is referred to as
Virtual Private Wire Service, VPWS.
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A variation of that service is a point to multipoint, non-broadcast
L2VPN. It differs only slightly from a more common point to point
VPN by offering more than one end point. The behavior of the VPN,
however, remains point to point by nature. The topology of such
VPNs can be fully meshed or partially meshed. In the latter case,
certain CEs, spokes of a hub, will see the VPN as a point to point
circuit. The VPN does not support broadcast and does not attempt to
interpret broadcast addresses. It is the responsibility of a CE
device to replicate packets in case broadcast emulation is
desirable.
4.2.2 Virtual Private LAN Service
The VPLS service attempts to emulate a broadcast domain, LAN-like,
behavior for the members of the VPN. The VPN provides the
capability to replicate packets and to interpret broadcast and
multicast addresses according to their meaning.
5 L2VPN Reference Model
The following diagram shows a L2VPN reference model where PE devices
provide a logical interconnect such that CE devices belonging to a
specific L2VPN appear to be connected by a single logical switching
instance.
+-----+ +-----+
+ CE1 +--+ +---| CE2 |
+-----+ | ........................ | +-----+
L2VPN A | +----+ +----+ | L2VPN A
+--| PE |--- Service ---| PE |--+
+----+ Provider +----+
/ . Backbone . \ - /\-_
+-----+ / . | . \ / \ / \ +-----+
+ CE4 +--+ . | . +--\ Access \----| CE5 |
+-----+ . +----+ . | Network | +-----+
L2VPN B .........| PE |......... \ / L2VPN B
+----+ ^ -------
| |
| |
+-----+ |
| CE3 | +-- Logical switching instance
+-----+
L2VPN A
5.1 Point to point L2VPN
The PE devices provide a logical interconnect such that a pair of CE
devices appear to be connected by a single logical L2 circuit.
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PE devices maintain separate L2VPN domains for each logical L2
circuit. Such domains are then mapped onto tunnels in the service
provider network. These tunnels can either be specific to a
particular L2VPN, or shared among several L2VPNs (e.g. as with MPLS
tunnel LSPs). In the above diagram, L2VPN B represents a point to
point case.
The CE-to-PE links can either be direct physical links, e.g.
100BaseTX, or logical links, e.g. ATM PVC, T1/E1 TDM, or RFC1490-
encapsulated link, over which L2 traffic is carried. The flavor of
the CE-PE L2 link is typically the same on each end, but it can be
different in case a proper interworking is provided e.g. ATM/FR
interworking, ARP mediation, or similar.
The PE-to-PE links carry tunneled L2 frames using different
tunneling technologies (e.g., GRE, IPSec, MPLS, L2TP, etc.).
Each PE device is responsible for allocating customer L2 frames to
the appropriate L2VPN and for proper forwarding to the intended end
nodes.
5.2 Point to multipoint, non-broadcast L2VPN
A non-broadcast point to multipoint L2VPN behaves similarly to a
point to point L2VPN. It differs in that there is more than one L2
destination reachable via a L2VPN instance. To the CE, it looks
like a collection of point to point circuits. The VPN does not
provide for packet replication, nor does it recognize broadcast
addresses. A CE can emulate broadcast by explicit replication by
each CE.
In the diagram above, L2VPN A can represent a point to multipoint
L2VPN. The L2VPN topology for the customer devices, CE1, CE2, and
CE3 can be hub and spoke or a full mesh. In the latter case, the
connectivity is frequently referred to as multipoint to multipoint.
In case of VPLS, the PE devices provide a logical interconnect such
that CE devices belonging to a specific VPLS appear to be connected
by a single logical Ethernet bridge. A VPLS can contain a single
VLAN or multiple, tagged VLANs.
Separate L2 broadcast domains are maintained on a per VPLS basis by
PE devices. Such domains are then mapped onto tunnels in the service
provider network. These tunnels can either be specific to a VPLS
(e.g. as with IP) or shared among several VPLSs (e.g. as with MPLS
tunnel LSPs). In the above diagram, the top PE routers maintain
separate forwarding instances for VPLS A and VPLS B.
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The CE-to-PE links can either be direct physical links, e.g.
100BaseTX, or logical links, e.g. ATM PVC, T1/E1 TDM, or RFC1490-
encapsulated link, over which bridged Ethernet traffic is carried.
The PE-to-PE links carry tunneled Ethernet frames using different
tunneling technologies (e.g., GRE, IPSec, MPLS, L2TP, etc.).
Each PE device learns remote MAC addresses, and is responsible for
proper forwarding of the customer traffic to the appropriate end
nodes. It is responsible for guaranteeing each VPLS topology is loop
free.
6 VPLS General Requirements
6.1 Layer 2 Domain representation
A L2VPN system MUST distinguish different customer domains. Each of
these customer domains MUST appear as a L2 network.
For the customer devices, the L2VPN domain SHOULD behave like a
native L2 network implied by the selected L2 protocol. For example,
if a CE connects to a L2VPN via a FR circuit, it should expect the
behavior of the VPN be similar to a connection to a true FR switch.
A L2VPN MAY span multiple service providers. Each L2VPN MUST carry a
unique identification within a L2VPN system. It is RECOMMENDED that
L2VPN identification be globally unique.
A provider's implementation of a L2VPN system SHOULD NOT constrain
the customer's ability to configure VPN topologies, or Layer 2
parameters related to the supported L2 protocol.
In case of VPLS, each domain MUST be capable of learning and
forwarding based on MAC addresses thus emulating an Ethernet virtual
switch to the customer CE devices attached to PEs.
A VPLS system MAY recognize customer VLAN identification. In that
case, a VLAN MUST be recognized in the context of the VPLS it is
part of. If customer VLANs are recognized, separate VLAN broadcast
domains SHOULD be maintained.
6.2 L2VPN Topology
The L2VPN system MAY be realized using one or more network tunnel
topologies to interconnect PEs, ranging from simple point-to-point
to distributed hierarchical arrangements. The typical topologies
include:
o point-to-point
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o point-to-multipoint, a.k.a. hub and spoke
o any-to-any, a.k.a. full mesh
o mixed, a.k.a. partial mesh
o hierarchical
Regardless of the topology employed, the service to the customers
MUST retain the connectivity type implied by the type of L2VPN. For
example, a non-broadcast point to multipoint VPN should allow point
to multipoint VPN connectivity even if implemented with point to
point circuits. This requirement does not imply that all traffic
characteristics (such as bandwidth, QoS, delay, etc.) be necessarily
the same between any two end points of a L2VPN.
6.3 Redundancy and Failure Recovery
The L2VPN infrastructure SHOULD provide redundant paths to assure
high availability. The reaction to failures SHOULD result in an
attempt to restore the service using alternative paths.
The intention is to keep the restoration time small. It is
RECOMMENDED that the restoration time be less than the time it
takes the CE devices to detect a failure in the L2VPN.
In cases where the provider knows a priori about impending changes
in network topology, the network SHOULD have the capability to
reconfigure without a loss, duplication, or re-ordering of customer
packets. This situation typically arises with planned network
upgrades or scheduled maintenance activities.
6.4 Policy Constraints
A L2VPN system MAY employ policy constraints governing various
interconnection attributes for L2VPN domains. Typical attributes
include:
o Selection of available network infrastructure
o QoS services needed
o Protection services needed
o Availability of higher level service access points (see 9.7 )
Policy attributes SHOULD be advertised via the L2VPN system's
control plane.
6.5 PE nodes
The PE nodes are the devices in the L2VPN system that store
information related to customer L2VPN domains and employ methods to
forward customer traffic based on that information. In this
document, the PE nodes are meant in logical sense. In the actual
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implementations, the PE nodes may be comprised of several physical
devices. Conversely, a single physical device may contain more than
one PE node.
All forwarding decisions related to customer L2VPN traffic MUST be
made by PE nodes. This requirement prohibits any other network
components from altering decisions made by PE nodes.
6.6 PE-PE Interconnection and Tunneling
A L2VPN system MUST provide for connectivity between each pair of PE
nodes. The connectivity is referred to as transport tunneling or
simply tunneling.
There are several choices for implementing transport tunnels. Some
popular choices include MPLS, IP in IP tunnels, variations of
802.1Q, etc. Regardless of the choice, the existence of the tunnels
and their operations MUST be transparent to the customers.
6.7 PE-CE Interconnection and Profiles
A L2VPN system MUST provide for connectivity between PE nodes and CE
nodes. That connectivity is referred to as CE access connection,
access connection, or simply access. Access connections MAY span
networks of other providers or public networks.
There are several choices for implementing access. Some popular
choices include Ethernet, ATM (DSL), Frame Relay, MPLS-based virtual
circuits etc.
In case of VPLS, the access connection MUST use Ethernet frames as
the Service Protocol Data Unit (SPDU).
A CE access connection MUST be bi-directional in nature.
PE devices MAY support multiple CE access connections on a single
physical interface. In such cases, PE devices MUST NOT rely on
customer controlled parameters, such as VLAN tags etc., for
distinguishing between different access connections.
A CE access connection, whether direct or virtual, MUST maintain all
committed characteristics of the customer traffic, such as QoS,
priorities etc. The characteristics of a CE access connection are
only applicable to that connection.
7 Control Plane Requirements
7.1 Provider Edge Signaling
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The control protocols SHOULD provide methods for signaling between
PEs. The signaling SHOULD inform of membership, tunneling
information, and other relevant parameters.
The infrastructure MAY employ manual configuration methods to
provide this type of information.
The infrastructure SHOULD use policies to scope the membership and
reachability advertisements for a particular L2VPN.
7.2 L2VPN Membership Discovery
The control protocols SHOULD provide methods to discover the PEs
which connect CEs forming a L2VPN.
7.3 Support for Layer 2 control protocols
A L2VPN system MUST ensure that loops be prevented. This can be
accomplished through a loop free topologies or appropriate
forwarding rules. In case of VPLS, control protocols such as
Spanning Tree or similar could be employed.
The L2VPN system's control protocols SHOULD allow transparent
operation of Layer 2 control protocols employed by customers.
In case of VPLS, a VPLS system's control protocols MAY use
indications from customer STP to improve the operation of a VPLS.
7.4 Scaling Requirements
In a L2VPN system, the control plane traffic increases with the
growth of L2VPN membership. Similarly, the control plane traffic
increases with the number of supported L2VPN domains. The rate of
growth of the associated control plane traffic SHOULD be linear.
The use of control plane resources increases with the number of
hosts connected to a L2VPN grows. The rate of growth of the demand
for control process resources SHOULD be linear. The control plane
MAY offer means for enforcing a limit on the number of customer
hosts attached to a L2VPN.
8 Data Plane Requirements
8.1 Transparency
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L2VPN service is intended to be transparent to Layer 2 customer
networks. It SHOULD NOT require any special packet processing by
the end users before sending packets to the provider's network.
8.2 Layer 2 Virtual Switching Instance
L2VPN Provider Edge devices MUST maintain a separate Virtual
Switching Instance (VSI) per each VPN. Each VSI MUST have
capabilities to forward traffic based on customer's traffic
parameters such as DLCI, VPI/VCI, MAC addresses, VLAN tags (if
supported), etc. as well as local policies.
L2VPN Provider Edge devices MUST have capabilities to classify
incoming customer traffic into the appropriate VSI.
In case of VPLS, Each VSI MUST have flooding capabilities for its
Broadcast Domain to facilitate proper forwarding of Broadcast,
Multicast and Unknown Unicast customer traffic.
8.3 Minimum MTU
The L2VPN service MUST support customer frames with payload 1500
bytes long. The service MAY offer support for longer frames.
The service MUST NOT fragment packets. Packets exceeding committed
MTU size MUST be discarded.
The committed minimum MTU size MUST be the same for a given instance
of L2VPN. Different L2VPN instances MAY have different committed MTU
sizes. In case of VPLS, if VLANs are supported, all VLANs within a
given VPLS MUST inherit the same MTU size.
8.4 QoS and packet re-ordering
A L2VPN system SHOULD have capabilities to enforce QoS parameters.
The queuing and forwarding policies SHOULD preserve packet order for
packets with the same QoS parameters.
The service SHOULD not duplicate packets.
8.5 Additional requirements for VPLS systems
8.5.1 Broadcast Domain
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The Broadcast Domain is defined as the flooding scope of a Layer 2
network. A separate Broadcast Domain MUST be maintained for each
VPLS.
In addition to VPLS Broadcast Domains, a VPLS system MAY recognize
customer VLAN Broadcast Domains. In that case, the system SHOULD
maintain a separate VLAN Broadcast Domain for each customer VLAN. A
VLAN Broadcast Domain MUST be a subset of the owning VPLS Broadcast
Domain.
8.5.2 MAC address learning
A VPLS service SHOULD derive all topology and forwarding information
from packets originating at customer sites. Typically, MAC
addresses learning mechanisms are used for this purpose.
In a VPLS system, MAC address learning MUST take place on a per
Virtual Switching Instance (VSI) basis, i.e. in the context of a
VPLS and, if supported, in the context of VLANs therein.
8.5.3 Unicast, Unknown Unicast, Multicast, and Broadcast forwarding
VPLS MUST be aware of the existence and the designated roles of
special MAC addresses such as Multicast and Broadcast addresses.
VPLS MUST forward these packets according to their intended
functional meaning and scope.
Broadcast packets MUST be flooded to all destinations.
Multicast packets MUST be flooded to all destinations. However, a
VPLS system MAY employ multicast snooping techniques, in which case
multicast packets SHOULD be forwarded only to their intended
destinations.
Unicast packets MUST be forwarded to their intended destinations.
Unknown Unicast packets MUST be flooded to all destinations in the
flooding scope of the VPLS (or VLAN). If the VPLS service relies on
MAC learning for its operations, it MUST assure proper forwarding of
packets with MAC addresses that have not been learned. Once
destination MAC addresses are learned, unicast packets SHOULD be
forwarded only to their intended destinations.
A provider MAY employ a method to limit the scope of flooding of
Unknown Unicast packets in cases where a customer desires to
conserve its bandwidth or wants to implement certain security
policies.
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8.5.4 Multilink Access
The VPLS service SHOULD support multilink access for CE devices.
The VPLS service MAY support multihome access for CE devices.
8.5.5 End-point VLAN tag translation
If VLANs are recognized, the VPLS system MAY support translation of
customers' VLAN tags. Such service simplifies connectivity of sites
that want to keep their tag assignments or sites that belong to
different administrative entities. In the latter case, the
connectivity is sometimes referred to as L2 extranet.
8.5.6 Support for MAC Services
VPLS are REQUIRED to provide MAC service compliant with IEEE 802.1D
specification [5] Section 6. Compliance with this section
facilitates proper operation of 802.1 LAN and seamless integration
of VPLS with bridged Local Area Networks. It is also useful to
compare [6], [7], and [8].
A MAC service in the context of VPLS is defined as the transfer of
user data between source and destination end stations via the
service access points using the information specified in the VSI.
1. A PE device that provides VPLS MUST NOT be directly accessed by
end stations except for explicit management purposes.
2. All MAC addresses MUST be unique within a given broadcast domain.
3. The topology and configuration of the VPLS MUST NOT restrict the
MAC addresses of end stations
9 Management and Operations Requirements
9.1 L2VPN configuration and monitoring
A L2VPN system MUST have capabilities to configure, manage, and
monitor its different components.
It SHOULD be possible to create several disjoint instances of L2VPN
systems within the same underlying network infrastructures.
The infrastructure SHOULD monitor all characteristics of the service
that are reflected in the customer SLA. This includes but is not
limited to bandwidth usage, packet counts, packet drops, service
outages, etc.
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9.2 L2VPN operations
The operations of a L2VPN systems is controlled by an administrative
authority, or admin. The admin is the originator of all operational
parameters of a L2VPN system. Conversely, the admin is also the
ultimate destination for the status of the L2VPN system and the
related statistical information. A typical L2VPN system spans
several such admins.
A L2VPN system MUST support proper dissemination of operational
parameters to all elements of a L2VPN system in the presence of
multiple admins.
A L2VPN system MUST employ mechanisms for sharing operational
parameters between different admins. These mechanism MUST NOT
assume any particular structure of the different admins. For
example the L2VPN should not be relying on admins forming a
hierarchy.
A L2VPN system SHOULD support policies for proper selection of
operational parameters coming from different admins. Similarly, a
L2VPN system SHOULD support policies for selecting information to be
disseminated to different admins.
A L2VPN system SHOULD employ discovery mechanisms to minimize the
amount of operational information maintained by the admins. For
example, if an admin adds or removes a customer port on a given PE,
the remaining PEs should determine the necessary actions to take
without the admins having to explicitly reconfigure those PEs.
9.3 CE Provisioning
The L2VPN MUST require only minimal or no configuration on the CE
devices, depending on the CE device that connects into the
infrastructure.
9.4 Customer traffic policing
The L2VPN service SHOULD provide the ability to police and/or shape
customer traffic entering and leaving the L2VPN system.
9.5 Dynamic Service Signaling
A Provider MAY offer to Customers an in-band method for selecting
services from the list specified in the SLA. A Provider MAY use the
same mechanism for reporting statistical data related to the
service.
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9.6 Class of Service Model
The L2VPN service MAY define a graded selection of classes of
traffic. These include, but are not limited to
o range of priorities
o best effort vs. guaranteed effort
o range of minimum delay characteristics
9.7 L3, and higher, service access point.
The L2VPN service SHOULD allow for a Provider based Service Access
Point for orderly injection of L3 or higher services to the
customers' VPLS segments.
In particular, the L2VPN system SHOULD allow to build L3VPN
services, including L3 interworking schemes such as ARP mediation or
similar, over its L2VPNs.
As a value added service, a Provider MAY offer access to other
services such as, IP gateways, storage networks, content delivery
etc.
9.8 Testing
The L2VPN service SHOULD provide the ability to test and verify
operational and maintenance activities on a per L2VPN basis, and in
case of VPLS, on a per VLAN basis.
9.9 Learning information from customer devices
The L2VPN service SHOULD provide means for limiting the amount of
information learned from customer devices.
For example, VPLS implementations typically limit the number of MAC
addresses learned from the customers' devices.
10 Security Requirements
10.1 Traffic separation
L2VPN system MUST provide traffic separation between different L2VPN
domains.
In case of VPLS, if VLANs are supported, the system MUST provide
traffic separation between customer VLANs within each VPLS domain.
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10.2 Provider network protection.
The L2VPN system MUST be immune to malformed or maliciously
constructed customer traffic. This includes but is not limited to
duplicate or invalid L2 addresses, short/long packets, spoofed
management packets, spoofed VLAN tags, high volume traffic, etc.
Additionally, L2VPN system MUST be immune to misconfigured or
maliciously set up customer network topologies. These include
customer side loops, backdoor links between sites, etc.
The L2VPN infrastructure devices MUST NOT be accessible from the
L2VPN.
10.3 Value added security services
Value added security services such as encryption and/or
authentication of customer packets, certificate management, and
similar are OPTIONAL.
Security measures employed by the L2VPN system SHOULD NOT restrict
implementation of customer based security add-ons.
11 References
1. Bradner, S., "The Internet Standards Process -- Revision 3", BCP
9, RFC 2026, October 1996.
2. Carugi, et al., "Service requirements for Provider Provisioned
Virtual Private Networks ", Work in progress, December 2001.
3. Augustyn, et al., "Requirements for Virtual Private LAN Services
(VPLS)", Work in progress, March 2002.
4. Bradner, S., "Key words for use in RFCs to Indicate Requirement
Levels", BCP 14, RFC 2119, March 1997.
5. IEEE Standard 802.1Q, "IEEE Standards for Local and Metropolitan
Area Networks: Virtual Bridged Local Area Networks", 1998.
6. IEEE Standard 802.1Q, "IEEE Standards for Local and Metropolitan
Area Networks: Virtual Bridged Local Area Networks", 1998.
7. IEEE Standard 802.1u-2001, "IEEE Standard for Local and
Metropolitan Area Networks: Virtual Bridged Local Area Networks -
Amendment 1: Technical and editorial corrections", 2001.
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8. IEEE Standard 802.1v-2001, "IEEE Standard for Local and
Metropolitan Area Networks: Virtual Bridged Local Area Networks -
Amendment 2: VLAN Classification by Protocol and Port", 2001.
12 Acknowledgments
We would like to acknowledge extensive comments provided by Loa
Anderson, Joel Halpern, and Eric Rosen. The authors, also, wish to
extend appreciations to their respective employers and various other
people who volunteered to review this work and provided feedback.
13 Authors' Addresses
Waldemar Augustyn
Email: waldemar@nxp.com
Giles Heron
PacketExchange Ltd.
The Truman Brewery
91 Brick Lane
London E1 6QL
United Kingdom
Email: giles@packetexchange.net
Vach Kompella
TiMetra Networks
274 Ferguson Dr.
Mountain View, CA 94043
Email: vkompella@timetra.com
Marc Lasserre
Riverstone Networks
5200 Great America Pkwy
Santa Clara, CA 95054
Phone: 408-878-6500
Email: marc@riverstonenet.com
Pascal Menezes
Terabeam
Phone: 206-686-2001
Email: pascal.menezes@terabeam.com
Augustyn, et al. Expires December 2002 17
draft-augustyn-ppvpn-l2vpn-requirements-00.txt June 2002
Hamid Ould-Brahim
Nortel Networks
P.O. Box 3511 Station C
Ottawa ON K1Y 4H7
Canada
Phone: 613-765-3418
Email: hbrahim@nortelnetworks.com
Tissa Senevirathne
Email: tsenevir@hotmail.com
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