Internet Working Group Y. Jiang
L. Yong
Internet Draft Huawei
M. Paul
Deutsche Telekom
Intended status: Standards Track F. Jounay
France Telecom Orange
Expires: September 2011 March 10, 2011
VPLS PE Model for E-Tree Support
draft-jiang-l2vpn-vpls-pe-etree-03.txt
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Abstract
A generic VPLS solution for E-Tree services is proposed which uses
VLANs to indicate root/leaf traffic. A VPLS Provider Edge (PE) model
is illustrated as an example for the solution. In the solution, E-
Tree VPLS PEs are interconnected by tagged PWs, the MAC address based
Ethernet forwarding engine and the PW works in the same way as before.
A signaling mechanism for E-Tree capability and VLAN mapping
negotiation is further described.
Table of Contents
1. Introduction.......................................... 2
2. Conventions used in this document..................... 4
3. Terminology........................................... 4
4. PE Model with E-Tree Support.......................... 4
4.1. Existing PE Models................................. 4
4.2. A New PE Model with E-Tree Support................. 7
5. PW for E-Tree Support................................. 8
5.1. Tagged Mode PW Encapsulation....................... 8
5.2. VLAN Mapping....................................... 8
5.3. PW Processing...................................... 9
5.3.1. PW Processing in the VLAN Mapping Mode ...... 9
5.3.2. PW Processing in the Compatible Mode......... 10
5.3.3. PW Processing in the Optimized Mode.......... 11
6. LDP Extensions for E-Tree Support..................... 12
7. BGP Extensions for E-Tree Support..................... 14
8. Applicability......................................... 14
9. Security Considerations............................... 14
10. IANA Considerations .................................. 14
11. References............................................ 15
11.1. Normative References............................ 15
11.2. Informative References.......................... 15
12. Acknowledgments....................................... 16
Appendix A. Other PE Models for E-Tree..................... 17
A.1. PE Model With a VSI and No bridge.................. 17
1. Introduction
The E-Tree service is defined in Metro Ethernet Forum (MEF) as a
Rooted-Multipoint EVC service, where traffic from a root can reach
any root or leaf, and traffic from a leaf can reach any root, but
should never reach a leaf. Further, two or more roots can be used to
enhance service reliability and flexibility. Although VPMS or P2MP
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multicast is a somewhat simplified version of this service, in fact,
there is no exact corresponding terminology in IETF.
[Etree-req] gives the requirements for providing E-Tree solutions in
the VPLS and the need to filter leaf to leaf traffic.
[vpls-etree] describes a PW control word based E-Tree solution, where
a bit in the PW control word is used to indicate the root/leaf
attribute for a packet. The Ethernet forwarder in the VPLS is also
extended to filter the leaf-leaf traffic based on the <ingress port,
egress port, CW L-bit> tuple.
[Etree-2PW] proposes another E-Tree solution where root and leaf
traffic are classified and forwarded in the same VSI but with two
separate PWs.
Both solutions are only applicable to "VPLS only" networks.
In fact, VPLS PE usually consists of a bridge module itself [RFC4664],
moreover, E-Tree services may cross both Ethernet and VPLS domains.
Therefore, the support of interconnection between Ethernet and VPLS
for an E-Tree service is indispensable.
IEEE 802.1 has incorporated the generic E-Tree solution in the latest
version of 802.1Q [802.1aq], which is just an improvement on the
traditional asymmetric VLAN mechanism. In the solution, VLANs are
used to indicate root/leaf attribute of a packet: one VLAN is used to
carry traffic originated from the roots and another VLAN is used to
carry traffic originated from the leaves. The bridge can then filter
on each leaf port all the traffic received on the VLANs associated
with the leaves. Therefore, it is better to use the same mechanism in
VPLS rather than develop a new mechanism which may not interwork with
Ethernet.
This document introduces how the Ethernet VLAN solution can be used
to support generic E-Tree services in the VPLS. The solution proposed
is fully compatible with the IEEE bridge architecture and the IETF
PWE3 technology, and VPLS scalability and simplicity is also well
kept. With this mechanism, it is also convenient to deploy a
converged E-Tree service across both Ethernet and MPLS networks.
As an example, a typical VPLS PE model is firstly introduced and
extended which consists of a Tree VSI connected to an S-VLAN bridge
with a dual-VLAN interface. However, this model is also applicable to
a PE with C-VLAN or B-VLAN as its service demarcation.
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This document then discusses the PW encapsulation and PW processing
such as VLAN mapping options for transporting E-Tree services in a
VPLS.
Finally, the extensions for the signaling of E-Tree capability and
VLAN mapping negotiation are also discussed.
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 [RFC2119].
3. Terminology
E-Tree: a Rooted-Multipoint EVC service according to the definition
in MEF
EVC: Ethernet Virtual Connection, as defined in MEF
T-VSI: Tree VSI, a VSI with E-Tree support
4. PE Model with E-Tree Support
"VPLS only" PE architecture as outlined in Fig. 1 of [Etree-req] is a
simplification of the VPLS and PWE3 architecture, the more common
VPLS PE architectures are discussed in more details in [RFC 4664] and
[vpls-interop].
Therefore, VLAN based E-Tree solution are demonstrated with the help
of a typical VPLS PE model. Other PE models are further discussed in
Appendix A.
4.1. Existing PE Models
According to [RFC4664], there are at least three models possible for
a VPLS PE, including:
o A single bridge module, a single VSI;
o A single bridge module, multiple VSIs;
o Multiple bridge modules, each attaches to a VSI.
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The second PE model is more commonly used, and a typical one
following it is depicted in Fig. 1 and Fig. 2 as per [vpls-interop],
where the S-VLAN bridge module is connected to multiple VSIs each
with a single VLAN virtual interface.
+-------------------------------+
| 802.1ad Bridge Module Model |
| |
+---+ | +------+ +-----------+ |
|CE |---------|C-VLAN|------| | |
+---+ | |bridge|------| | |
| +------+ | | |
| o | S-VLAN | |
| o | | |
| o | Bridge | |
+---+ | +------+ | | |
|CE |---------|C-VLAN|------| | |
+---+ | |bridge|------| | |
| +------+ +-----------+ |
+-------------------------------+
Figure 1 The Model of 802.1ad Bridge Module
+----------------------------------------+
| VPLS-capable PE model |
| +---------------+ +------+ |
| | | |VSI-1 |------------
| | |==========| |------------ PWs
| | Bridge ------------ |------------
| | | S-VLAN-1 +------+ |
| | Module | o |
| | | o |
| | (802.1ad | o |
| | bridge) | o |
| | | o |
| | | S-VLAN-n +------+ |
| | ------------VSI-n |-------------
| | |==========| |------------- PWs
| | | ^ | |-------------
| +---------------+ | +------+ |
| | |
+-------------------------|--------------+
LAN emulation Interface
Figure 2 VPLS-capable PE Model
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In this PE model, Ethernet service from the CEs will cross multiple
stages of bridge modules (i.e., C-VLAN and S-VLAN bridge) and a VSI
in a PE to access the egress PWs. Therefore, the association of an AC
port and a PW in a single forwarding engine as required in [vpls-
etree] or [Etree-2PW] is difficult, sometimes even impossible.
This model could be further enhanced by the introduction of a trunk
VLAN and a branch VLAN as Ethernet frames enter the PE. To be more
precise, they are called root and leaf VLAN respectively in this
document. All the egress traffics from the root VLAN are transmitted
both on the roots and the leaves, while egress traffics from the leaf
VLAN are transmitted on the roots but dropped on the leaves (these
VLANs are removed before the frames are transmitted over the wire).
It was demonstrated in [802.1aq] that the E-Tree service in Ethernet
networks can be well supported with this mechanism.
Assume this mechanism is implemented in the bridge module, then it is
quite straightforward to infer a VPLS PE model with two VSIs to
support the E-Tree (as shown in Fig. 3). But this model will require
two VSIs per PE and two sets of PWs per E-Tree service, which is
poorly scalable in a large MPLS/VPLS network.
+----------------------------------------+
| VPLS-capable PE model |
| +---------------+ +------+ |
| | | |VSI-1 |------------
| | |==========| |------------ PWs
| | Bridge ------------ |------------
| | | Root +------+ |
| | Module | S-VLAN o |
| | | o |
| | (802.1ad | o |
| | bridge) | o |
| | | Leaf o |
| | | S-VLAN +------+ |
| | ------------VSI-2 |-------------
| | |==========| |------------- PWs
| | | ^ | |-------------
| +---------------+ | +------+ |
| | |
+-------------------------|--------------+
LAN emulation Interface
Figure 3 VPLS PE Model for E-Tree with 2 VSIs
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4.2. A New PE Model with E-Tree Support
To provide for the E-Tree support in a more scalable way, a new VPLS
PE model with a single Tree VSI (T-VSI, a VSI with E-Tree support) is
proposed and depicted in Fig. 4, where the S-VLAN bridge module is
connected to the T-VSI with a dual-VLAN virtual interface. That is,
both the root S-VLAN and the leaf S-VLAN are connected to the T-VSI.
In this way, only one VPLS instance and one set of PWs is needed per
E-Tree service. With this model, multiple E-Trees can also be
provided by the same T-VSI if needed, and further increase the
scalability of VPLS.
+----------------------------------------+
| VPLS-capable PE model |
| +---------------+ +------+ |
| | |==========|TVSI-1|------------
| | ------------ |------------ PWs
| | Bridge ------------ |------------
| | | Root & +------+ |
| | Module | Leaf VLAN o |
| | | o |
| | (802.1ad | o |
| | bridge) | o |
| | | o |
| | | S-VLAN-n +------+ |
| | ------------VSI-n |-------------
| | |==========| |------------- PWs
| | | ^ | |-------------
| +---------------+ | +------+ |
| | |
+-------------------------|--------------+
LAN emulation Interface
Figure 4 VPLS PE Model for E-Tree with a Single T-VSI
In this model, both VLANs should share the same FIB and work in
shared VLAN learning. The traffic from the root UNIs are firstly
tagged with root C-VLAN by the C-VLAN bridge module, and then tagged
with root S-VLAN by the S-VLAN bridge module, thus can only be
transported on the root S-VLAN. Similarly, the traffic from the
leaves can only be transported on the leaf S-VLAN.
In fact, this model can also be applied to a PE with C-VLAN (customer
sites attached to the PEs with untagged ports), or B-VLAN (with a PBB
bridge module embedded in the PE) as a provider's service demarcation.
Therefore, the document will use the VLAN in its more general meaning
in the latter sections.
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5. PW for E-Tree Support
5.1. Tagged Mode PW Encapsulation
For a VPLS instance to support an E-Tree service, its Ethernet PW
should work in the tagged mode (PW type 0x0004) as described in
[RFC4448], and a VLAN tag must be carried in each frame in the PW to
indicate the E-Tree root/leaf attribute.
A pair of T-VSIs in a VPLS is interconnected with a bidirectional PW.
The VLAN indicating root/leaf attribute of the packet is carried in
the PW, and the peer PE must drop all the packets with a leaf VLAN on
each egress port associated with a leaf.
5.2. VLAN Mapping
There are three ways of manipulating VLANs for an E-Tree:
o Global VLAN based that is, provisioning two global VLANs across
both the Ethernet and the VPLS instance domain, no VLAN mapping is
needed for this case.
o Partial global VLAN based, that is, provisioning two local VLANs
in the VLAN space for each Ethernet domain and two global VLANs in
the VPLS network domain, the VLAN mapping is done completely in
the Ethernet domains (e.g., in the bridge module of the PE or in
the Ethernet device attached to the PE), and not needed at all in
the VPLS domain.
o Local VLAN based, that is, provisioning two local VLANs
independently for the VPLS on each PE.
The first two methods require no VLAN mapping in the PW, but two
unique VLANs must be allocated in the VPLS (they may be provisioned
by management or signaled by some control protocols), and the PW
processing procedure as described in RFC 4448 applies.
The last method is more scalable in the use of VLANs, but needs a
VLAN mapping mechanism in the PW similar to what is already described
in Section 4.3 of [RFC4448]. It is assumed that for each PE with E-
Tree capability there is a VLAN mapping module that can be enabled
when VLAN mapping is needed for a PW. Actual VLAN mapping mode can be
provisioned or determined by a signaling protocol as described in
Section 6 when PW is being established.
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5.3. PW Processing
5.3.1.PW Processing in the VLAN Mapping Mode
In the VLAN Mapping mode, two VPLS PEs with E-Tree capability are
inter-connected with a PW (For example, the scenario of Fig. 5
depicts the interconnection of two PEs miscellaneously attached with
roots and leaves).
+--------------------------------+
| VPLS PE with T-VSI |
| |
+----+ | +------+ +-------+ +-----+ | PW
|Root|------|C-VLAN|---|S-VLAN |---|T-VSI|----------
+----+ | | BRG | | BRG | | |----------
+----+ | | |---| |---| |----------
|Leaf|------| | | | | |---------+
+----+ | +------+ +-------| +-----+ | |
| | |
+--------------------------------+ |
|
+--------------------------------+ |
| VPLS PE with T-VSI | |
| | |
+----+ | +------+ +-------+ +-----+ | PW |
|Root|------|C-VLAN|---|S-VLAN |---|T-VSI|---------+
+----+ | | BRG | | BRG | | |----------
+----+ | | |---| |---| |----------
|Leaf|------| | | | | |----------
+----+ | +------+ +-------| +-----+ |
| |
+--------------------------------+
Figure 5 T-VSI Interconnected in the Normal Mode
If a PE is in the VLAN mapping mode for a PW, then in the data plane
the PE MUST map the VLAN in each packet as follows:
o Upon transmit on the PW, map from local VLAN to remote VLAN (i.e.,
the local leaf VLAN in a frame is translated to the remote leaf
VLAN; the local root VLAN in a frame is translated to the remote
root VLAN).
o Upon receive on the PW, map from remote VLAN to local VLAN, and
the packet is further forwarded or dropped in the egress bridge
module using the filtering mechanism as described in IEEE 802.1Q.
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5.3.2.PW Processing in the Compatible Mode
The new VPLS PE model can work in a traditional VPLS network
seamlessly in the compatibility mode. As shown in Fig. 6, the VPLS PE
with T-VSI can access root and/or leaf nodes, while the VPLS PE with
a traditional VSI can only access root nodes.
+--------------------------------+
| VPLS PE with T-VSI |
| |
+----+ | +------+ +-------+ +-----+ | PW
|Root|------|C-VLAN|---|S-VLAN |---|T-VSI|----------
+----+ | | BRG | | BRG | | |----------
+----+ | | |---| |---| |----------
|Leaf|------| | | | | |---------+
+----+ | +------+ +-------| +-----+ | |
| | |
+--------------------------------+ |
|
+--------------------------------+ |
| VPLS PE with VSI | |
| | |
+----+ | +------+ +-------+ +-----+ | PW |
|Root|------|C-VLAN|---|S-VLAN |---|VSI |---------+
+----+ | | BRG | | BRG | | |----------
+----+ | | |---| | | |----------
|Root|------| | | | | |----------
+----+ | +------+ +-------| +-----+ |
| |
+--------------------------------+
Figure 6 T-VSI interconnected with Traditional VSI
If a PE is in the Compatible mode for a PW, then in the data plane
the PE MUST map the VLAN in each packet as follows:
o Upon transmit on the PW, map both local root and local leaf VLAN
to the remote VLAN.
o Upon receive on the PW, map the remote VLAN to the local root VLAN.
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5.3.3.PW Processing in the Optimized Mode
When two VPLS PE with T-VSI are inter-connected and one PE (e.g., PE2)
is attached with pure leaves, as shown in the scenario of Fig. 6, the
peer PE (e.g., PE1) should then work in the optimization mode, that
is, the PE1 can drop all the frames received over the local leaf VLAN
rather than transport them over the PW and be discarded on the remote
PE. Thus bandwidth efficiency of the VPLS can be improved. The
signaling for the PE with pure leaves is specified in Section 6.
+--------------------------------+
| VPLS PE with T-VSI (PE1) |
| |
+----+ | +------+ +-------+ +-----+ | PW
|Root|------|C-VLAN|---|S-VLAN |---|T-VSI|----------
+----+ | | BRG | | BRG | | |----------
+----+ | | |---| |---| |----------
|Leaf|------| | | | | |---------+
+----+ | +------+ +-------| +-----+ | |
| | |
+--------------------------------+ |
|
+--------------------------------+ |
| VPLS PE with T-VSI (PE2) | |
| | |
+----+ | +------+ +-------+ +-----+ | PW |
|Leaf|------|C-VLAN|---|S-VLAN |---|T-VSI|---------+
+----+ | | BRG | | BRG | | |----------
+----+ | | |---| |---| |----------
|Leaf|------| | | | | |----------
+----+ | +------+ +-------| +-----+ |
| |
+--------------------------------+
Figure 7 T-VSI interconnected with 1-side of pure Leaves
If a PE is in the Optimized Mode for a PW, then in the data plane,
before proceeding as listed in Section 5.3.1 upon transmit, the PE
SHOULD first operate as follows:
o Drop a frame if it has a local leaf VLAN.
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6. LDP Extensions for E-Tree Support
To dynamically provision the E-Tree service and negotiate a single PE
to carry out the VLAN mapping function using the signaling procedures
as specified in [RFC4447], an E-Tree specific interface parameter
sub-TLV is proposed as follows:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| E-Tree | Length=8 | Reserved |P|V|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Root VLAN ID | Leaf VLAN ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 8 E-Tree Sub-TLV
Where:
o E-Tree is the sub-TLV identifier to be assigned by IANA.
o Length is the length of the sub TLV in octets.
o Reserved bits MUST be set to zero on transmit and be ignored on
receive.
o P is a Pure Leaf bit, it is set to 1 to indicate that the PE is
attached with all leaves, and set to 0 otherwise.
o V is a bit indicating the sender's VLAN mapping capability. A PE
capable of VLAN mapping MUST set this bit, and clear it otherwise.
o Root VLAN ID is the value of the local root VLAN.
o Leaf VLAN ID is the value of the local leaf VLAN.
When the VPLS supporting an E-Tree service is setting up the PW, the
PW endpoints negotiate the E-Tree support using the above E-Tree sub-
TLV. Note PW type of 0x0004 should be used during the PW negotiation.
A PE that wishes to support E-Tree service includes an E-Tree Sub-TLV
in its PW label mapping message, with its local root VLAN and leaf
VLAN carried in the Root VLAN ID and Leaf VLAN ID field respectively.
A PE that has the VLAN mapping capability MUST set the V bit to 1,
and a PE is attached with pure leaves SHOULD set the P bit to 1.
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In default, for each PW, VLAN-Mapping-Mode, Compatible-Mode, and
Optimized-Mode are all set to FALSE.
A PE that receives a PW label mapping message with an E-Tree Sub-TLV
from its peer PE must process it as follows:
1) if the root and leaf VLAN ID in the message match the local root
and leaf VLAN ID, then exit;
2) else {
if the bit V is cleared, then {
if the PE is capable of VLAN mapping, then it MUST set
VLAN-Mapping-Mode to TRUE;
else {
A label release message with the error code "E-Tree
VLAN mapping not supported" is sent to the peer PE
and exit the process;
}
}
if the bit V is set, and the PE is capable of VLAN mapping,
then the PE with the minimum IP address MUST set VLAN-Mapping-
Mode to TRUE;
}
3) If the P bit is set, then:
{
If the PE is a pure leaf node itself, then a label release
message with the error code "Leaf to Leaf PW error" is sent to the
peer PE and exit the process;
Else the PE SHOULD set the Optimized-Mode to TRUE.
}
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If a PE has sent an E-Tree Sub-TLV but does not receive any E-Tree
Sub-TLV in its peer's PW label mapping message, then set Compatible-
Mode to TRUE if the PE is VLAN mapping capable, otherwise a label
release message is sent.
Data plane processing for this PW is as following:
If VLAN-Mapping-Mode is TRUE, then data plane processing is as
described in Section 5.3.1.
If Optimized-Mode is TRUE, then data plane processing is as
described in Section 5.3.3.
If Compatible-Mode is TRUE, then data plane processing is as
described in Section 5.3.2.
PW processing as described in RFC 4448 proceeds as usual.
7. BGP Extensions for E-Tree Support
BGP may also be used to distribute the E-Tree and VLAN mapping
information. It is to be specified in the next version.
8. Applicability
The solution is applicable to LDP VPLS [RFC4762] and may also be
applicable to BGP VPLS [RFC 4761].
The solution is applicable to both "VPLS Only" network and VPLS with
Ethernet aggregation network.
9. Security Considerations
To be added in the next version.
10. IANA Considerations
IANA is requested to allocate a value for E-Tree in the Pseudowire
Interface Parameters Sub-TLV type registry.
Parameter ID Length Description
=======================================
TBD 8 E-Tree
IANA is requested to allocate a new LDP status code from the registry
of name "STATUS CODE NAME SPACE". The following value is suggested:
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Range/Value E Description
------------- ----- ----------------------
TBD 0 E-Tree VLAN mapping not supported
11. References
11.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC4447] Martini, L., and et al, "Pseudowire Setup and Maintenance
Using Label Distribution Protocol (LDP)", RFC 4447, April
2006.
[RFC4448] Martini, L., and et al, "Encapsulation Methods for
Transport of Ethernet over MPLS Networks", RFC 4448, April
2006.
[RFC4762] Lasserre, M. and Kompella, V., "Virtual Private LAN
Services using LDP", RFC 4762, January 2007.
11.2. Informative References
[RFC3985] Bryant, S., and Pate, P., "Pseudo Wire Emulation Edge-to-
Edge (PWE3) Architecture", RFC 3985, March 2005.
[RFC4664] Andersson, L., and Rosen, E., "Framework for Layer 2
Virtual Private Networks (L2VPNs)", RFC 4664, September
2006.
[vpls-interop] Sajassi, A., and et al, "VPLS Interoperability with CE
Bridges", draft-ietf-l2vpn-vpls-bridge-interop-06, October
2010
[ETree-req] Key, R., et al, "Requirements for MEF E-Tree Support in
VPLS", draft-key-l2vpn-vpls-etree-reqt-02, October 2010
[vpls-etree] Delord, S., and et al, "Extension to VPLS for E-Tree",
draft-key-l2vpn-vpls-etree-04, October 2010
[802.1aq] IEEE 802.1aq D3.0, Virtual Bridged Local Area Networks -
Amendment 9: Shortest Path Bridging, June 2010
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[Etree-2PW] Ram, R., and et al., Extension to LDP-VPLS for E-Tree
Using Two PW, draft-ram-l2vpn-ldp-vpls-etree-2pw-00.txt,
October 2010
12. Acknowledgments
The authors would like to thank Adrian Farrel and Susan Hares for
their valuable comments and advices.
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Appendix A. Other PE Models for E-Tree
A.1. PE Model With a VSI and No bridge
If there is no bridge module in a PE, the PE may consist of Native
Service Processors (NSPs) as shown in Figure A.1 (adapted from Fig. 5
of [RFC3985]) where any transformation operation for VLANs (e.g.,
VLAN insertion/removal or VLAN mapping) may be applied. Thus a root
VLAN or leaf VLAN can be added by the NSP depending on the UNI type
(root/leaf) associated with the AC over which the packet arrives.
Further, when a packet with a leaf VLAN exits a forwarder and arrives
at the NSP, the NSP must drop the packet if the egress AC is
associated with a leaf UNI.
Tagged PW and VLAN mapping work in the same way as in the typical PE
model.
+----------------------------------------+
| PE Device |
Multiple+----------------------------------------+
AC | | | Single | PW Instance
<------>o NSP # + PW Instance X<---------->
| | | |
|------| VSI |----------------------|
| | | Single | PW Instance
<------>o NSP #Forwarder + PW Instance X<---------->
| | | |
|------| |----------------------|
| | | Single | PW Instance
<------>o NSP # + PW Instance X<---------->
| | | |
+----------------------------------------+
Figure A.1 PE model with a VSI and no bridge module
Jiang, et al Expires September 10, 2011 [Page 17]
Internet-Draft VPLS PE Model for E-Tree March 2011
Authors' Addresses
Yuanlong Jiang
Huawei Technologies Co., Ltd.
Bantian, Longgang district
Shenzhen 518129, China
Email: jiangyuanlong@huawei.com
Lucy Yong
Huawei USA
1700 Alma Dr. Suite 500
Plano, TX 75075, USA
Email: lucyyong@huawei.com
Manuel Paul
Deutsche Telekom
Goslarer Ufer 35
10589 Berlin, Germany
Email: manuel.paul@telekom.de
Frederic Jounay
France Telecom Orange
2, avenue Pierre-Marzin
22307 Lannion Cedex, France
Email: frederic.jounay@orange-ftgroup.com
Jiang, et al Expires September 10, 2011 [Page 18]