Tagging Bridge Domains in VPLS
draft-zhang-l2vpn-vpls-bd-tagging-00
The information below is for an old version of the document.
| Document | Type |
This is an older version of an Internet-Draft whose latest revision state is "Expired".
|
|
|---|---|---|---|
| Authors | Mingui Zhang , Bin Wang , Liang Xia | ||
| Last updated | 2013-12-19 | ||
| RFC stream | (None) | ||
| Formats | |||
| Stream | Stream state | (No stream defined) | |
| Consensus boilerplate | Unknown | ||
| RFC Editor Note | (None) | ||
| IESG | IESG state | I-D Exists | |
| Telechat date | (None) | ||
| Responsible AD | (None) | ||
| Send notices to | (None) |
draft-zhang-l2vpn-vpls-bd-tagging-00
INTERNET-DRAFT Mingui Zhang
Intended Status: Proposed Standard Bin Wang
Expires: June 22, 2014 Liang Xia
Huawei
December 19, 2013
Tagging Bridge Domains in VPLS
draft-zhang-l2vpn-vpls-bd-tagging-00.txt
Abstract
When customers' Bridge Domains (BD) are interconnected using Virtual
Private LAN Service, traffic of these BDs need be separated. This
proposal suggests to use the service tag as a further de-multiplexor
besides Pseudo-Wire to distinguish customers' BDs. Use cases are
explored in this document.
Status of this Memo
This Internet-Draft is submitted to IETF in full conformance with the
provisions of BCP 78 and BCP 79.
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."
The list of current Internet-Drafts can be accessed at
http://www.ietf.org/1id-abstracts.html
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html
Copyright and License Notice
Copyright (c) 2013 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
Mingui Zhang, et al Expires June 22, 2014 [Page 1]
INTERNET-DRAFT BD Interconnection Using VPLS December 19, 2013
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Acronyms and Terminology . . . . . . . . . . . . . . . . . . . 3
2.1. Acronyms . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Example Network . . . . . . . . . . . . . . . . . . . . . . . . 3
4. Use Cases . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
4.1. No Duplicated MAC Address . . . . . . . . . . . . . . . . . 4
4.2. BUM Traffic Scoped per BD . . . . . . . . . . . . . . . . . 4
4.3. Scalable Interconnection of L2 Sites . . . . . . . . . . . 5
4.4. Per S-tag Pruning and Dynamic VLAN Registration . . . . . . 5
5. Security Considerations . . . . . . . . . . . . . . . . . . . . 5
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 5
7. References . . . . . . . . . . . . . . . . . . . . . . . . . . 5
7.1. Normative References . . . . . . . . . . . . . . . . . . . 5
7.2. Informative References . . . . . . . . . . . . . . . . . . 6
Author's Addresses . . . . . . . . . . . . . . . . . . . . . . . . 7
Mingui Zhang, et al Expires June 22, 2014 [Page 2]
INTERNET-DRAFT BD Interconnection Using VPLS December 19, 2013
1. Introduction
When VPLS is used to interconnect customers' layer2 networks,
operators used to establish one VSI for each BD. When there is a
large number of BDs need be interconnected, for example, in the
environment of Data Center Networks, a lot of PWs must be set up [V-
aware]. This kind of solution is not so scalable.
This document suggests a service tag is used as an additional de-
multiplexor of customers' BDs besides PW. By doing this, lots of BDs
can share the same PW, which can greatly reduce the configuration
overhead of PWs for operators and make the proposal be scalable. For
example, if S-VLAN is used as the service tag, as many as 4094 BDs
can be bundled in one PW.
2. Acronyms and Terminology
2.1. Acronyms
MVRP: Multiple VLAN Registration Protocol
BD: Bridge Domain/Broadcast Domain
PW: Pseudo-Wire
VSI: Virtual Switch Instance
S-tag: Service tag
S-VLAN: Service VLAN
C-VLAN: Customer VLAN
BUM: Broadcast, Unknown unicast and Multicast
VLL: Virtual Leased Line
2.2. Terminology
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].
3. Example Network
Mingui Zhang, et al Expires June 22, 2014 [Page 3]
INTERNET-DRAFT BD Interconnection Using VPLS December 19, 2013
+--------+
L2 +--------+ BD1 | PW
L2 +--------+Stag=1 +----------------------
L2 +---+ +--------+
|
| +----------------------+
| | +---+---+ |
| | +--------+ |100|PKT| |
+----+ BD11 | +---+---+ |
L2 +--------+Stag=100+--------------+
L2 + | +--------+ | |
L2 + | +---+---+ | |
L2 + | +--------+ |200|PKT| | |
L2 +--------+ BD12 | +---+---+ | | PW
| |Stag=200+--------------+--------
| +--------+ | |
| +---+---+ | |
| +--------+ |300|PKT| | |
L2 +--------+ BD13 | +---+---+ | |
L2 +--------+Stag=300+--------------+
L2 + | +--------+ |
L2 + | VSI|
L2 + +----------------------+
L2 + PW
L2 +-----------VLL---------------------------
Figure 3.1: Service tag as the de-multiplexor
In Figure 3.1, an example is used to shown that service tag is used
as an finer grained de-multiplexor along with PW for traffic
segregation. Therefore, multiple BDs can be integrated into one VSI.
4. Use Cases
4.1. No Duplicated MAC Address
For a specific Customer VLAN (C-VLAN) in different BDs, one MAC may
be used by different hosts, which is illegal but it is the reality.
If these BDs share the same PW, hosts in this C-VLAN will join in the
same bridge domain. It therefore causes the MAC duplication issue.
If operators use S-tag as the de-multiplexor, traffic of customers'
BDs are separated. Above MAC duplication issue is avoided.
4.2. BUM Traffic Scoped per BD
Suppose a customer has four sites in New York, Chicago, Atlanta and
Dallas. BD1 = {New York, Chicago and Atlanta} while BD2 = {New York,
Mingui Zhang, et al Expires June 22, 2014 [Page 4]
INTERNET-DRAFT BD Interconnection Using VPLS December 19, 2013
Chicago and Dallas}. If one PW is set up to interconnect customers
four sites. BUM traffic of Atlanta site will be poured to Dallas
site, and vice versa.
When the S-tag is used, the BUM traffic can be confined per BD. For
above example, the operator need use two S-tags to distinguish the
two BDs. In this way, BUM traffic of Atlanta site will be confined in
BD1 and BUM traffic for Dallas site will be confined in BD2. This
increases the efficiency of the bandwidth utilization of BUM traffic.
4.3. Scalable Interconnection of L2 Sites
For the per PW bundling, when the connections (topologies) of sites
in different BDs are different, operators used to set up different
VSI to distinguish these BDs. The worst case is to set up one VSI per
BD. This causes the scalability issue when there is a mass of BDs
need be inter-connected.
In this document, S-tag is used to distinguish BDs further, operators
need not set up that many PWs. As shown in Figure 3.1, one PW is set
up for each VSI and this VSI may be an integration of multiple BDs.
4.4. Per S-tag Pruning and Dynamic VLAN Registration
Multiple VLAN Registration Protocol (MVRP) can be used for per-
service-tag registration. For PEs connected by a PW, MVRP is used to
register service tags configured on customers' BDs. Only when an S-
tag is registered in both directions on this PW, BUM traffic with
this S-tag can be transmitted on this PW. In this way, distributions
trees of the BUM traffic is pruned.
Since MVRP is used, operators need not reconfigure VLANs on their
network devices when customers change their VLAN configuration.
5. Security Considerations
This document raises no new security issues. For general security
considerations, refer to [RFC4761] and [RFC4762].
6. IANA Considerations
This document requires no IANA actions. RFC Editor: please remove
this section before publication.
7. References
7.1. Normative References
Mingui Zhang, et al Expires June 22, 2014 [Page 5]
INTERNET-DRAFT BD Interconnection Using VPLS December 19, 2013
[V-aware] D. Cai, S. Boutros, and et al, "VLAN Aware VPLS services",
draft-cai-l2vpn-vpls-vlan-aware-bundling-00.txt, working in
progress
7.2. Informative References
[RFC4761] Kompella, K., Ed., and Y. Rekhter, Ed., "Virtual Private
LAN Service (VPLS) Using BGP for Auto-Discovery and
Signaling", RFC 4761, January 2007.
[RFC4762] Lasserre, M., Ed., and V. Kompella, Ed., "Virtual Private
LAN Service (VPLS) Using Label Distribution Protocol (LDP)
Signaling", RFC 4762, January 2007.
Mingui Zhang, et al Expires June 22, 2014 [Page 6]
INTERNET-DRAFT BD Interconnection Using VPLS December 19, 2013
Author's Addresses
Mingui Zhang
Huawei Technologies
Email: zhangmingui@huawei.com
Bin Wang
Huawei Technologies
Email: wb.wangbin@huawei.com
Liang Xia
Huawei Technologies
Email: frank.xialiang@huawei.com
Mingui Zhang, et al Expires June 22, 2014 [Page 7]