U.S. patent application number 14/489625 was filed with the patent office on 2015-01-01 for backbone provider bridging networks.
This patent application is currently assigned to ROCKSTAR CONSORTIUM US LP. The applicant listed for this patent is Rockstar Consortium US LP. Invention is credited to Paul Bottorff, Norival Figueira, Marc Holness.
Application Number | 20150003295 14/489625 |
Document ID | / |
Family ID | 35782313 |
Filed Date | 2015-01-01 |
United States Patent
Application |
20150003295 |
Kind Code |
A1 |
Bottorff; Paul ; et
al. |
January 1, 2015 |
Backbone Provider Bridging Networks
Abstract
An edge device is used to support a backbone provider bridging
network to facilitate interconnection of a plurality of networks.
The edge device is coupled between the backbone and a first one of
the networks, and is operable to encapsulate data units received
from the first network with a header, and to forward the
encapsulated data unit to the backbone. The header is indicative of
a tunnel that is used to support traffic from the first network to
a second network over the backbone. The edge device also
de-encapsulates data units received from the backbone that are
destined for the first network.
Inventors: |
Bottorff; Paul; (Palo Alto,
CA) ; Figueira; Norival; (Campbell, CA) ;
Holness; Marc; (Ottawa, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Rockstar Consortium US LP |
Plano |
TX |
US |
|
|
Assignee: |
ROCKSTAR CONSORTIUM US LP
Plano
TX
|
Family ID: |
35782313 |
Appl. No.: |
14/489625 |
Filed: |
September 18, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11159065 |
Jun 22, 2005 |
8855122 |
|
|
14489625 |
|
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60582316 |
Jun 23, 2004 |
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Current U.S.
Class: |
370/254 |
Current CPC
Class: |
H04L 12/4633 20130101;
H04L 41/0893 20130101; H04L 12/4625 20130101; H04L 12/2852
20130101; H04L 12/4658 20130101 |
Class at
Publication: |
370/254 |
International
Class: |
H04L 12/46 20060101
H04L012/46; H04L 12/24 20060101 H04L012/24 |
Claims
1. A method of interconnecting a first provider bridge network and
a second provider bridge network, comprising: providing a backbone
provider bridge network, the backbone provider bridge network
comprising a first backbone provider bridge edge device for
connection to the first provider bridge network and a second
backbone provider bridge edge device for connection to the second
provider bridge network, the first backbone provider bridge edge
device being coupled to the second provider bridge edge device over
the backbone provider bridge network; and configuring the first
backbone provider bridge device: to receive a data unit from the
first provider bridge network, the data unit having a header
comprising a Service Virtual Local Area Network (S-VLAN) Identifier
which is associated with the first and second provider bridge
networks; to encapsulate the received data unit with a Backbone
VLAN Identifier (B-VID) which is indicative of a backbone VLAN
tunnel to be used to transport the S-VLAN over the backbone
provider bridge network and an Extended S-VLAN Identifier (ES-VID)
which is associated with the S-VLAN Identifier (S-VID); and to
forward the encapsulated data unit over the backbone VLAN tunnel
toward the second backbone provider bridge edge device.
2. The method of claim 1, further comprising forwarding the
encapsulated data unit over the backbone VLAN tunnel toward the
second backbone provider bridge edge device.
3. The method of claim 2, wherein: the backbone provider bridge
network comprises a third backbone provider bridge edge device
which is associated with the S-VLAN; the backbone VLAN tunnel is a
point to multi-point tunnel linking the first backbone provider
bridge edge device to the second and third backbone provider bridge
edge devices; and forwarding the encapsulated data unit over the
backbone VLAN tunnel comprises forwarding the encapsulated data
unit over the backbone VLAN tunnel toward both the second and third
backbone provider bridge edge devices.
4. The method of claim 1, comprising configuring the second
backbone provider bridge edge device: to receive the encapsulated
data unit forwarded from the first backbone provider bridge device;
to decapsulate the encapsulated data unit by removing the B-VID;
and to forward the decapsulated data unit to the second provider
bridge network.
5. The method of claim 2, comprising: configuring the second
backbone provider bridge edge device: to receive the encapsulated
data unit forwarded from the first backbone provider bridge device;
to decapsulate the encapsulated data unit by removing the B-VID;
and to forward the decapsulated data unit to the second provider
bridge network based on the S-VID; and forwarding the decapsulated
data unit to the second provider bridge network.
6. The method of claim 1, comprising configuring the first backbone
provider bridge edge device: to receive an encapsulated data unit
forwarded from the second backbone provider bridge device, the
encapsulated data unit having a header comprising the B-VID; to
decapsulate the encapsulated data unit by removing the B-VID; and
to forward the decapsulated data unit to the first provider bridge
network.
7. The method of claim 2, comprising: configuring the first
backbone provider bridge edge device: to receive an encapsulated
data unit forwarded from the second backbone provider bridge
device, the encapsulated data unit having a header comprising the
B-VID; to decapsulate the encapsulated data unit by removing the
B-VID; and to forward the decapsulated data unit to the first
provider bridge network; and forwarding the decapsulated data unit
to the first provider bridge network.
8. The method of claim 1, wherein configuring the first backbone
provider bridge edge device to encapsulate the received data unit
with an ES-VID comprises configuring the first backbone bridge
device to replace the S-VID with the ES-VID and the B-VID.
9. The method of claim 5, wherein configuring the second backbone
provider bridge edge device to decapsulate the encapsulated data
unit comprises configuring the second backbone provider bridge edge
device to replace the ES-VID and the B-VID with the S-VID.
10. The method of claim 6, wherein configuring the first backbone
provider bridge edge device to decapsulate the encapsulated data
unit comprises configuring the first backbone provider bridge edge
device to replace the ES-VID and the B-VID with the S-VID.
11. The method of claim 1, wherein the backbone provider bridge
network comprises: a first domain comprising the first backbone
provider bridge edge device; a second domain comprising the second
backbone provider bridge edge device; and a third domain comprising
a third backbone provider bridge edge device coupled to the first
domain and a fourth backbone provider bridge edge device coupled to
the second domain, the fourth backbone provider bridge edge device
being coupled over the third domain to the third backbone provider
bridge edge device.
12. The method of claim 11, wherein: the first domain uses a first
B-VID to forward data units over a tunnel in the first domain which
is associated with the first and second provider bridge networks;
the second domain uses a second B-VID to forward data units over a
tunnel in the second domain which is associated with the first and
second provider bridge networks; and the third domain uses a third
B-VID to forward the data units over a tunnel in the third domain
which is associated with the first and second provider bridge
networks.
13. The method of claim 12, wherein the third backbone provider
bridge edge device is configured to insert the third B-VID in data
units received from the first domain having the first B-VID for
forwarding of the received data units over the third domain.
14. The method of claim 13, wherein the third backbone provider
bridge edge device is configured to insert the third B-VID in data
units received from the first domain having the first B-VID by
swapping the third B-VID for the first B-VID.
15. The method of claim 13, wherein the fourth backbone provider
bridge edge device is configured to insert the second B-VID in
received data units having the third B-VID for forwarding of the
received data units over the second domain to the second backbone
provider edge device.
16. The method of claim 15, wherein the fourth backbone provider
bridge edge device is configured to insert the second B-VID in
received data units having the third B-VID by swapping the second
B-VID for the third B-VID.
17. The method of claim 1, wherein the backbone provider bridge
network is a multi-layer hierarchical network.
18. The method of claim 17, comprising using B-VID swapping at
boundaries between layers in the multilayer hierarchical network to
forward data units over respective selected tunnels in the layers
of the multilayer hierarchical network.
19. The method of claim 18, wherein B-VIDs are selected for data
units received at boundaries between layers in the multi-layer
hierarchical network based on ES-VIDs carried by the data
units.
20. The method of claim 17, comprising B-VID stacking at boundaries
between layers in the multi-layer hierarchical network to forward
data units selectively over respective tunnels at each layer of the
multilayer hierarchical network.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This Application is a continuation of U.S. patent
application Ser. No. 11/159,065, filed Jun. 22, 2005, titled
Backbone Provider Bridging Networks, which a claims priority to
U.S. Provisional Patent Application Ser. No. 60/582,316, entitled
Backbone Provider Bridging Networks, filed Jun. 23, 2004, which is
incorporated by reference.
FIELD OF THE INVENTION
[0002] This invention relates generally to the field of network
communications, and more particularly to interconnection of
provider bridge networks.
BACKGROUND OF THE INVENTION
[0003] Entry of new communications service providers into the
marketplace combined with the breakup of some state-regulated
communications monopolies has resulted in increased network
complexity. In particular, communications services that might once
have been supplied by a single service provider may now require
interaction between the individual bridge networks of multiple
service providers. Pairs of provider bridge networks may be
interconnected on a 1:1 basis using bridges. However, these bridges
are costly, and the number of bridges required to interconnect
multiple service providers in a mesh increases exponentially
relative to the number of service providers. Further, the frame
replicators needed to connect a large number of points limits
performance.
[0004] The problem is further exacerbated because multipoint
connection circuits are becoming increasingly important in provider
networks as providers deploy more diverse service offerings.
Existing techniques for interconnection of provider bridged
networks have poor scaling properties for multipoint connection
circuits. This is in part due to the limits of current technologies
which have difficulty scaling the number of replicator elements
required to support traffic splitting for multipoint connections
and the fact that the number of possible multipoint paths grows as
2**N, where N is the number of nodes.
SUMMARY OF THE INVENTION
[0005] In accordance with one embodiment of the invention,
apparatus for facilitating interconnection of a plurality of
provider networks includes an edge device coupled between a
backbone and a first one of the provider networks, the edge device
being operable to encapsulate data units received from the first
provider network with a header, and to forward the encapsulated
data unit to the backbone, the header being indicative of a tunnel
that is used to support traffic from the first provider network
over the backbone.
[0006] In accordance with another embodiment of the invention, a
method for facilitating interconnection of a plurality of provider
networks includes the steps of: encapsulating, by an edge device,
data units received from a first provider network with a header,
the header being indicative of a tunnel that is used to support
traffic from the first provider network over the backbone; and
forwarding the encapsulated data unit to the backbone.
[0007] In accordance with another embodiment of the invention, a
method for facilitating transporting a plurality of point-to-point,
point-to-multipoint, and multi-point-to-multipoint connections over
a carrier network includes the steps of: encapsulating, by an edge
device data units received from a first provider bridge with a
header, the header being indicative of a tunnel that is used to
support traffic from point in the provider network to one or many
other points in the provider network; and forwarding the
encapsulated data unit.
[0008] One advantage of the invention is that the edge devices
support hierarchical backbones that are readily scalable. In
addition, the hierarchy created in the backbones creates relatively
small multicast domains, each domain having a small number of
bridges. With such an arrangement, the number of multipoint tunnels
and replication is limited, and scaling is greatly improved.
BRIEF DESCRIPTION OF THE FIGURES
[0009] FIG. 1 illustrates a Backbone Provider Bridge Network
("BPBN") for interconnecting multiple Provider Bridge Networks
("PBNs").
[0010] FIG. 2 illustrates an alternative embodiment without
PBNs.
[0011] FIG. 3 illustrates use of multi-point B-VLANs in the BPBN of
FIG. 1.
[0012] FIG. 4 illustrates a simple BPBN hierarchy.
[0013] FIG. 5 illustrates a multi-level BPBN hierarchy.
DETAILED DESCRIPTION
[0014] Referring now to FIG. 1, a Provider Bridge Networks ("PBNs")
(100, 102, 104, 106) are individually used to interconnect
different aggregation points (108) in the respective networks of
different service providers. For example, a PBN may interconnect
Points-of-Presence ("PoPs"), Central Offices ("COs"), and
enterprise customers. A Backbone Provider Bridging Network ("BPBN")
(110) is used to interconnect the PBNs. In particular, a single
BPBN (110) may be used to interconnect any number of PBNs. Thus,
the BPBN is a single resource across which a PBN can exchange
communication with all other PBNs. In the illustrated example the
BPBN interconnects with the PBNs via IEEE 802.1ad interfaces.
[0015] FIG. 2 illustrates an alternative embodiment in which the
BPBN is operated without PBNs. In the illustrated example the BPBN
(110) interconnects switch/routers (120) and a server (122)
associated with one or more service provider networks. However, the
BPBN may be employed to interconnect any suitable network equipment
and types of networks. Further, although illustrated as a ring
architecture, the BPBN can be implemented as a mesh or any other
suitable architecture.
[0016] FIG. 3 illustrates communications across the BPBN (110) of
FIG. 1 in greater detail. The BPBN includes Backbone-VLANs
("B-VLANs") (200, 202) which interconnect selected PBNs. For
example, B-VLAN (200) interconnects PBN (100), PBN (102), PBN (104)
and PBN (106). B-VLAN (202) interconnects PBN (102) and PBN (104).
Each B-VLAN supports at least one Service-VLAN ("S-VLAN"). S-VLANs
can provide point-to-point communications between pairs of PBNs.
For example, S-VLAN (204) and S-VLAN (206) each interconnect PBN
(102) with PBN (104) via B-VLAN (202). Similarly, S-VLAN (208)
interconnects PBN (102), PBN (104) and PBN (106) via B-VLAN (200).
Further, S-VLAN (210) interconnects PBN (100) with PBN (102) via
B-VLAN (200). In one embodiment point-to-point S-VLANs interconnect
every possible PBN pairing, and all S-VLANs are carried on a single
multi-point B-VLAN, thereby providing interconnection between all
endpoints.
[0017] Backbone Provider Bridge Edge ("BBPB") devices (212, 214,
216, 218, 220, 222) facilitate operation of the B-VLANs and
S-VLANs. Each PBN is associated with at least one BBPB device. Each
BBPB is operable to encapsulate frames received from its associated
PBN and destined for a different PBN. In particular, the BBPB
encapsulates the frames in a data unit having a BPBN header. The
BPBN header includes an Extended Service-VLAN Identifier ("ES-VID")
which identifies the S-VLAN associated with the PBN S-VIDs on the
BPBN. The BPBN header also includes a Backbone-VLAN Identifier
("B-VID"). The B-VID identifies a Backbone VLAN tunnel that is used
to transport the S-VLANs over the BPBN. B-VLAN tunnels can be
point-to-point or multi-point in nature. Each BBPB is further
operable to receive encapsulated frames from corresponding BBPBs
associated with other PBNs. Upon receipt of an encapsulated frame
from another PBN the BBPB is operative to de-encapsulate the frame
by removing the BPBN header. The frame is then forwarded toward its
destination in the target PBN.
[0018] Referring now to FIGS. 4 and 5, a BPBN (300, 400) may be
organized hierarchically to facilitate scaling. The BPBN
illustrated in FIG. 4 has a single layer hierarchy while the BPBN
illustrated in FIG. 5 has a two layer hierarchy. It should be noted
that any number of layers can be implemented. In the single-layer
embodiment BBPBs (301) are connected by a BackBone ("BB") device
(302). The BBPB edge devices (301) encapsulate PBN frames received
from associated Provider Bridge ("PB") devices (304). In
particular, the BBPB devices (301) encapsulate the frames with a
BPBN header by swapping the S-VID to/from a larger ES-VID and
creating a B-VID from the ES-VID. The BBPB edge devices (301) also
de-encapsulate frames to be transmitted to associated PBN devices
(304) by stripping the BPBN header, swapping the ES-VID to an S-VID
for the PBN, and removing the final B-VID. Both S-VID and ES-VID
identify the S-VLAN carried through the PBNs and BPBN.
[0019] In the case of the multi-layer hierarchy illustrated in FIG.
5, BB-BB layer edge bridge devices (401) interconnect BPBN layers.
In particular, the BB-BB devices (401) swap the B-VID of frames to
a new B-VID based on the ES-VID. The new B-VID allows transport
over the current BPBN multicast domain ("MC-DOM"). Source route
addressing (with Backbone Connectivity identifier stacking) can
also be used to avoid the need for table lookups and B-VID swapping
at layer boundaries. The ES-VID is the same throughout the BPBN.
The ES-VID is swapped with the S-VID at the BB-PB edge. The B-VID
is preferably large enough to address all possible multi-point
tunnels within a given layer domain, e.g., 12 bits is enough to
support twelve BB bridges in a layer. One advantage of hierarchical
BPBNs is that they are readily scalable. In addition, the hierarchy
of BPBN bridges creates relatively small multicast domains, each
domain having a small number of bridges. With such an arrangement,
the number of multipoint tunnels in any single domain and
replication in any single domain is limited, while the number of
multipoint tunnels throughout the network becomes limitless.
[0020] While the invention is described through the above exemplary
embodiments, it will be understood by those of ordinary skill in
the art that modification to and variation of the illustrated
embodiments may be made without departing from the inventive
concepts herein disclosed. Moreover, while the preferred
embodiments are described in connection with various illustrative
structures, one skilled in the art will recognize that the system
may be embodied using a variety of specific structures. For
example, the BPBN may be implemented with or without PBNs.
Accordingly, the invention should not be viewed as limited except
by the scope and spirit of the appended claims.
* * * * *