Network Working Group Wataru Imajuku
Internet Draft NTT
draft-imajuku-ml-routing-02.txt Eiji Oki
Expiration Date: December 2002 NTT
Kohei Shiomoto
NTT
Satoru Okamoto
NTT
June 2002
Multilayer routing using multilayer switch capable LSRs
draft-imajuku-ml-routing-02.txt
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Copyright Notice
Copyright (C) The Internet Society (2002). All Rights Reserved.
Abstract
The integration of multilayer switching capabilities within one
box, such as the packet-switch capability (PSC) and the lambda-
switch capability (LSC) under the MPLS/Generalized-MPLS control
mechanism, paves the way for achieving network resource optimization
considering multilayer routing. This document clarifies the model of
the GMPLS-controlled integrated PSC/LSC label switch router (LSR)
and discusses the requirements of the routing extensions needed to
achieve optimized multilayer traffic engineering.
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1. Summary for Sub-IP Area
1.1. Summary
This document adds extensions to the routing protocols
with GMPLS extensions in order to support multilayer routing.
1.2. Where does it fit in the picture of the Sub-IP Work
This work fits in the CCAMP.
1.3. Why is it targeted at this WG
This draft is targeted at the CCAMP WG, because this draft specifies
the extensions to routing protocols to support multilayer routing
of hierarchical label switched paths in the GMPLS network.
This type of multilayer routing in the GMPLS network is within the
scope of the CCAMP WG.
1.4. Justification
The WG should consider this document as it specifies the extensions
to routing protocols in support of multilayer routing of hierarchical
label switched paths in the GMPLS network.
2. Introduction
Generalized-MPLS (GMPLS) facilitates the realization of seamless
integration of IP Networks with legacy SDH/SONET or Photonic
networks. In particular, integration of the packet switching
capability and the photonic switching technology under a unified
GMPLS control plane would significantly enhance the forwarding
capacity of the IP network, while greatly reducing number
of network elements to be managed in an IP network [Sato02].
One of the other forces driving the construction of a unified
GMPLS control plane is the desire to implement a multilayer routing
capability, which would enable effective network resource
utilization of both the IP-layer and the SDH/SONET or Photonic-layer
in the next generation high capacity IP+Photonic network [Oki02].
In such a network, each LSR would contain multiple-type switching
capabilities such as PSC and Time-Division-Multiplexing
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(or SDH/SONET XC) (TDM), PSC and Lambda switching (LSC), and LSC and
Fiber switching (FSC) under the unified GMPLS control plane.
These LSRs with integrated switch capabilities are required to hold
and advertise resource information of not only link states and network
topology, but also those of the portion of internal LSR resources to
terminate hierarchical label switched paths (LSPs), since circuit switch
capable units such as TDMs, LSCs, and FSCs require rigid resources.
For example, an LSR with the PSC+LSC integrated switching capability
can forward an optical label switched path (O-LSP) but can never
terminate the O-LSP, if there is no unused adaptation capability
between the PSC and the LSC.
Therefore, the concept of advertising adaptation capability to
terminate LSPs, within such multilayer LSRs is essential to
establishing multilayer route calculation of LSPs.
This concept enables a local LSR to discriminate remote LSRs based on
whether or not they have the adaptation capability to terminate O-LSPs
at PSCs within the remote LSRs. This realizes multilayer routing such
that the electrical label switched path (E-LSP) set-up automatically
triggers new O-LSP set-up and successfully forwards IP traffic
even if there is no existing O-LSP.
This draft proposes the idea of discriminating the forwarding
capability and adaptation capability of each switching capability
in the LSR. Then, this draft proposes to redefine the interface
switching capability descriptor discussed in [GMPLS-ROUT] and
[GMPLS-OSPF] as the information describing the forwarding capability
of each switching capability in LSRs, and to add an interface
adaptation capability descriptor disseminating the LSP termination
capability within multilayer LSRs. The content of this document is
as follows. First, the need for redefinition and addition of these
descriptors is discussed. Second, a format is proposed for the
interface adaptation capability descriptor. Third, usage examples are
provided of a redefined interface switching capability descriptor
and interface adaptation capability descriptor for several kinds of
multilayer LSRs.
3. Interface adaptation capability descriptor
This draft proposes that the interface switching capability descriptor
be re-interpreted as the forwarding capability information from
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an in-bound interface to an out-bound interface of a switch capability.
Also, this draft proposes an interface adaptation capability
descriptor that can be interpreted as the adaptation capability
information from an in-bound interface to the adaptation capability or
from the adaptation capability to an out-bound interface of the switch
capability. By introducing such a re-definition and new descriptor,
the routing engine can swiftly search which LSRs can terminate a certain
encoding type of LSP and successfully establish an LSP tunnel between
two PSCs.
As an example, this section considers an E-LSP+O-LSP multiple
networking layer domain comprising PSC LSRs, LSC LSRs, and PSC+LSC LSRs.
In the networking domain, an E-LSP networking layer has an E-LSP
switching capability such as PSC-LSRs or PSC+LSC LSRs, and the links
combining these LSRs are O-LSPs. On the other hand, the O-LSP networking
layer has an O-LSP switching capability such as LSC-LSRs or PSC+LSC-LSRs,
and the links combining these LSRs are fiber links. Therefore, the LSRs
within this multiple networking layer domain shall have both these link
states, i.e., not only fiber links but also O-LSPs, to select correctly
routes of E-LSPs.
The LSRs discriminates the type of these links by the interface
switching capability descriptor in LSAs [LSP-HIER]. The interface
switching capability at both ends of a TE-link shall be [LSC, LSC],
[PSC, LSC], or [TDM, LSC] for fiber links carrying a "lambda" label.
On the other hand, the interface switching capability at both ends of
a TE-link shall be [PSC, PSC] for O-LSPs that carry a "shim" header
label, or shall be [TDM, TDM] or [PSC, TDM] for O-LSPs carrying "TDM
time slot" labels. Based on the interface switching capability descriptor,
the LSRs can impose proper constraints in order to calculate the route of
LSPs. For example, LSRs can understand that a remote TDM LSR with
[TDM, LSC] link cannot forward O-LSPs, but can terminate O-LSPs and
switch the "TDM time slot".
However, LSRs cannot properly understand the O-LSP termination
capability of remote LSRs, especially if the LSRs have a hybrid switch
architecture such as a PSC+TDM+LSC LSR as shown below. In the LSR,
LSC may have a direct inner interface not only to TDM but also to PSC.
The O-LSP can be terminated by both DXC and PSC. This kind of hybrid
architecture shall be very common in Photonic networks.
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_______
______| |______
| __| PSC |__ |
| | |_______| /|\ |
| \|/ _______ | |
| |__| |__| /|\
\|/ __| DXC |__ |
| | |_______| /|\ |
| \|/ _______ | |
| |__| |__| |
|______| |______|
| |
__\ /|___| |___|\
/ | |___| |___| | Fiber #1
========| |___| LSC |___| |========
| |___| |___| |
\| | | |/
| |
. .
. .
__\ /|___| |___|\
/ | |___| |___| | Fiber #N
========| |___| |___| |========
| |___| |___| |
\| | | |/
|_______|
The problem with the use of the interface switching capability
descriptor at the PSC+TDM+LSC LSR is the shortage of LSP termination
capability information. The PSC+TDM+LSC LSRs provides only switching
capability information, in other words, the forwarding capability
information for each switching capability. Therefore, remote LSRs
cannot properly understand which switching capability O-LSPs can be
terminated at the PSC+TDM+LSC LSR. In the LSR, an O-LSP can be
terminated both by the PSC and TDM, but the interface switch
capability descriptor cannot provide sufficient information for O-LSP
termination capability in the PSC+TDM+LSC LSR.
Similar circumstances can occur, if a switching fabric that supports
both PSC and L2SC functionalities is assembled with LSC with "lambda"
(photonic) encoding. In the switching fabric, some interfaces terminate
O-LSPs and perform L2 switching, other interfaces terminate O-LSPs and
perform L3 switching.
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Thus, the interface switching capability descriptor provides the
information mainly for the forwarding capability. In order for remote
LSRs to understand properly the termination capability of LSRs, the
addition of new information to the interface switching capability
descriptor is essential in achieving seamless multilayer routing in
a multiple layer networking domain. This approach can achieve seamless
routing such as an E-LSP set-up signaling automatically triggering new
O-LSPs between the LSRs that do not have a preferred O-LSP to carry the
E-LSP with the knowledge of both the fiber and O-LSP link state, even
if multiple kinds of switching capabilities are assembled with LSCs
by miscellaneous switching architectures.
4. Encoding of interface adaptation capability descriptor
The interface adaptation capability descriptor is sub-TLV (of type TBD)
of Link TLV (with type TBD) [OSPF-TE]-[ISIS-TE]. The length is the
length of the value field in octets. The reason for defining new sub-TLV
for the interface adaptation capability descriptor is to achieve simple
and swift look-up of LSA-DB. The routing engine can ignore this sub-TLV
at a cut-through LSR, and only look-up this sub-TLV at LSRs at which
LSPs are terminated.
Sub-TLV Type Length Name
15 variable Interface Switching Capability Descriptor
TBD variable Interface Adaptation Capability Descriptor
The format of the value field is as shown below:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Switching Cap |Num. ADP Types | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Enc. Type 1 |Client S.Type 1| G-PID 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Bandwidth Encoding 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Number of Adaptations 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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| Number of Unreserved Adaptations 1 at priority 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Number of Unreserved Adaptations 1 at priority 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Number of Unreserved Adaptations 1 at priority 3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Number of Unreserved Adaptations 1 at priority 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Number of Unreserved Adaptations 1 at priority 5 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Number of Unreserved Adaptations 1 at priority 6 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Number of Unreserved Adaptations 1 at priority 7 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Enc. Type 2 |Client S.Type 2| G-PID 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Bandwidth Encoding 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Number of Adaptations 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Number of Unreserved Adaptations 2 at priority 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Number of Unreserved Adaptations 1 at priority 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
...
...
| Number of Unreserved Adaptations n at priority 5 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Number of Unreserved Adaptations n at priority 6 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Number of Unreserved Adaptations n at priority 7 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The Switching Capability (Switching Cap): 8 bits
This field contains one of the following values:
1 Packet-Switch Capable-1 (PSC-1)
2 Packet-Switch Capable-2 (PSC-2)
3 Packet-Switch Capable-3 (PSC-3)
4 Packet-Switch Capable-4 (PSC-4)
51 Layer-2 Switch Capable (L2SC)
100 Time-Division-Multiplex Capable (TDM)
150 Lambda-Switch Capable (LSC)
200 Fiber-Switch Capable (FSC)
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Number of adaptation types (Number of IF Types): 8 bits
This field contains a number between 0-255, which describes number
of adaptation capability types connected to the client switching
capability on the master switching capability described in the
Switching Cap field.
Encoding type (Enc. Type): 8 bits
This field indicates the type of LSP that can be terminated by
the adaptation capability. The values are defined in [GMPLS-SIG].
Client switching capable type (Client S. Type): 8 bits
This field describes the client switching capability. This field
contains one of the values described in the explanation of the
Switching Cap field above.
Generalized-PID (G-PID): 16 bits
An identifier of the payload carried by an LSP that can be
terminated by the adaptation capability. The values are defined
in [GMPLS-SIG].
Bandwidth Encoding: 32 bits
Bandwidth encoding describes the bandwidth of an LSP that can be
terminated by the adaptation capability.
The values are defined in [GMPLS-SIG].
Number of Adaptations: 32 bits
The value of this field describes number of adaptation capabilities
with the above described attribute.
Number of Unreserved Adaptations: 32 bits
The value of this field describes number of unreserved adaptation
capabilities with the above described attribute.
5. Example of interface adaptation capability descriptor
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5.1 PSC+LSC LSR
_______
_________| |_________
| ______| PSC |______ |
| | __| |__ | /|\
\|/ | | |_______| | /|\ |
| \|/ | /|\ | |
| | \|/ _______ | | |
| | |__| |__| | |
| |______| |______| |
|_________| |_________|
| |
__\ /|___| PXC |___|\
/ | |___| |___| | Fiber #1
========| |___| |___| |========
| |___| |___| |
\| | | |/
|_______|
The first example is PSC+LSC-LSR. The PSC has both STM-16 POS and
STM-64 POS interfaces. The LSC itself is a transparent PXC so that
the LSC can forward not only an SDH encoded O-LSP but also an Ethernet
encoded O-LSP. In this case, the fiber interface of the LSR advertises
the interface switching capability descriptor as follows:
Interface Switching Capability Descriptor 1:
Interface Switching Capability = PSC-1
Encoding = SDH
Max LSP Bandwidth[p] = 2.5 Gbps, for all p
Interface Switching Capability Descriptor 2:
Interface Switching Capability = PSC-1
Encoding = SDH
Max LSP Bandwidth[p] = 10.0 Gbps, for all p
and
Interface Switching Capability Descriptor 3:
Interface Switching Capability = LSC
Encoding = Lambda (photonic)
Reservable Bandwidth = Determined by optical technology limits
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The LSR also advertises the interface adaptation capability descriptor
as follows:
Interface Adaptation Capability Descriptor:
Switching Capability = LSC
Number of IF Types = 2
Encoding 1 = SDH
Client S. Type 1 = PSC-1
G-PID 1 = POS - Scrambling, 16 bit CRC
Bandwidth Encoding 1[p] = 2.5 Gbps, for all p
Number of Adaptations 1 = 1
Number of Unreserved Adaptations 1 = variable
Encoding 2 = SDH
Client S. Type 2 = PSC-1
G-PID 2 = POS - Scrambling, 16 bit CRC
Bandwidth Encoding 2[p] = 10.0 Gbps, for all p
Number of Adaptations 2 = 2
Number of Unreserved Adaptations 2 = variable
5.2 PSC/L2SC+LSC LSR
_______
_________| |_________
| ______| PSC/ |______ |
| | __| L2SC |__ | /|\
\|/ | | |_______| | /|\ |
| \|/ | /|\ | |
| | \|/ _______ | | |
| | |__| |__| | |
| |______| |______| |
|_________| |_________|
| |
__\ /|___| PXC |___|\
/ | |___| |___| | Fiber #1
========| |___| |___| |========
| |___| |___| |
\| | | |/
|_______|
The second example is PSC/L2SC+LSC-LSR. The PSC/L2SC have STM-16 POS
interfaces. The LSC itself is a transparent PXC
so that the LSC can forward not only an SDH encoded O-LSP but
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also an Ethernet encoded O-LSP. In this case, the fiber interface of
the LSR advertises the interface switching capability descriptor
as follows:
Interface Switching Capability Descriptor 1:
Interface Switching Capability = PSC-1
Encoding = SDH
Max LSP Bandwidth[p] = 2.5 Gbps, for all p
Interface Switching Capability Descriptor 2:
Interface Switching Capability = L2SC
Encoding = SDH
Max LSP Bandwidth[p] = 2.5 Gbps, for all p
and
Interface Switching Capability Descriptor 3:
Interface Switching Capability = LSC
Encoding = Lambda (photonic)
Reservable Bandwidth = Determined by optical technology limits
The LSR also advertises the interface adaptation capability descriptor
as follows:
Interface Adaptation Capability Descriptor:
Switching Capability = LSC
Number of IF Types = 2
Encoding 1 = SDH
Client S. Type 1 = PSC-1
G-PID 1 = POS - Scrambling, 16 bit CRC
Bandwidth Encoding 1 [p] = 2.5 Gbps, for all p
Number of Adaptations 1 = 3
Number of Unreserved Adaptations 1 = variable
Encoding 2 = SDH
Client S. Type 2 = L2SC
G-PID 2 = POS - Scrambling, 16 bit CRC
Bandwidth Encoding 2 [p] = 2.5 Gbps, for all p
Number of Adaptations 2 = Shared with above one
Number of Unreserved Adaptations 2 = none
5.3 DXC+LSC LSR
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_______
_________| |_________
| ______| DXC |______ |
| | __| |__ | /|\
\|/ | | |_______| | /|\ |
| \|/ | /|\ | |
| | \|/ _______ | | |
| | |__| |__| | |
| |______| |______| |
|_________| |_________|
| |
__\ /|___| PXC |___|\
/ | |___| |___| | Fiber #1
========| |___| |___| |========
| |___| |___| |
\| | | |/
DWDM |_______|
The second example is PSC+LSC-LSR. The STM-16 interface of this Digital
Cross Connect (DXC) supports two types of SDH multiplexing hierarchy.
The LSC itself is a transparent PXC with external DWDM so that the
LSC can forward not only STM-16 encoded O-LSP but also an STM-64
encoded O-LSP and so on. In this case, the fiber interface of the LSR
advertises the interface switching capability descriptor as follows:
Interface Switching Capability Descriptor:
Interface Switching Capability = TDM
Encoding = SDH
Min LSP Bandwidth[p] = VC-3
Max LSP Bandwidth[p] = STM-16, for all p
Interface Switching Capability Descriptor:
Interface Switching Capability = TDM
Encoding = SDH
Min LSP Bandwidth[p] = VC-4
Max LSP Bandwidth[p] = STM-16, for all p
and
Interface Switching Capability Descriptor:
Interface Switching Capability = LSC
Encoding = SDH
Reservable Bandwidth = Determined by DWDM
The fiber interface of the LSR also advertises the interface
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adaptation capability descriptor as follows:
Interface Adaptation Capability Descriptor:
Switching Capability = LSC
Number of IF Types = 1
Encoding = SDH
Client S. Type = TDM
G-PID = Byte Synchronous mapping of E1
Bandwidth Encoding [p] = 2.5 Gbps, for all p
Number of Adaptations = 3
Number of Unreserved Adaptations = variable
5.4 PSC+DXC+LSC LSR
_______
______| |______
| __| PSC |__ |
| | |_______| /|\ |
| \|/ _______ | |
| |__| |__| /|\
\|/ __| DXC |__ |
| | |_______| /|\ |
| \|/ _______ | |
| |__| |__| |
|______| |______|
| |
__\ /|| ||\
/ | || || | Fiber #1
========| || OXC || |========
| || || |
\|| ||/
DWDM|_______|
(SDH framed)
The third example is PSC+DXC+LSC-LSR. The O-LSP can be terminated
by both DXC and PSC. This example assumes that DWDM and OXC are
connected in such a way that each interface on the OXC handles
multiple wavelengths individually. In this case, an interface at
the OXC is considered to be LSC, and not FSC. A TE link is a group
of one or more of the interfaces at the OXC. All lambdas associated
with a particular interface are required to have identifiers unique
to that interface, and these identifiers are used as labels
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(see 3.2.1.1 of [GMPLS-SIG]).
The adaptation capability of LSC is directly faced with both DXC and
PSC. These interfaces are STM-16 interfaces. The STM-16 interface of
the DXC supports two types of SDH multiplexing hierarchy. The DXC also
has the interface faced with PSC and whose interface type is the STM-16
POS interface. In this case, the fiber interface of the LSR advertises
the interface switching capability descriptor as follows:
Interface Switching Capability Descriptor:
Interface Switching Capability = PSC-1
Encoding = SDH
Max LSP Bandwidth[p] = 2.4 Gbps, for all p
Interface Switching Capability Descriptor:
Interface Switching Capability = TDM
Encoding = SDH
Min LSP Bandwidth[p] = VC-3
Max LSP Bandwidth[p] = STM-16, for all p
Interface Switching Capability Descriptor:
Interface Switching Capability = TDM
Encoding = SDH
Min LSP Bandwidth[p] = VC-4
Max LSP Bandwidth[p] = STM-16, for all p
and
Interface Switching Capability Descriptor:
Interface Switching Capability = LSC
Encoding = SDH
Reservable Bandwidth = STM-16
The fiber interface of the LSR also advertises the interface adaptation
capability descriptor as follows:
Interface Adaptation Capability Descriptor 1:
Switching Capability = LSC
Number of IF Types = 2
Encoding 1 = SDH
Client S. Type 1 = PSC-1
G-PID 1 = POS - Scrambling, 16 bit CRC
Bandwidth Encoding 1 [p] = 2.5 Gbps, for all p
Number of Adaptations 1 = 1
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Number of Unreserved Adaptations 1 = variable
Encoding 2 = SDH
Client S. Type 2 = TDM
G-PID 2 = Byte Synchronous mapping of E1
Bandwidth Encoding 2 [p] = 2.5 Gbps, for all p
Number of Adaptations 2 = 1
Number of Unreserved Adaptations 2 = variable
and
Interface Adaptation Capability Descriptor 2:
Switching Capability = TDM
Number of IF Types = 1
Encoding = SDH
Client S. Type = PSC-1
G-PID = POS - Scrambling, 16 bit CRC
Bandwidth Encoding [p] = 2.5 Gbps, for all p
Number of Adaptations = 1
Number of Unreserved Adaptations = variable
As discussed in these examples, the dissemination of the interface
adaptation capability descriptor helps to search correctly LSRs
to terminate LSPs routed by circuit switch capabilities such as FSC,
LSC, and TDM.
6. Security Considerations
Security issues are not discussed in this draft.
7. References
[Sato02] K.-I. Sato, N. Yamanaka, Y. Takigawa, M. Koga, S. Okamoto,
K. Shiomoto, E. Oki, and W. Imajuku, "GMPLS-Based Photonic Multilayer
Router (Hikari Router) Architecture: An Overview of Traffic Engineering
and Signaling Technology," IEEE Comm. Mag., vol. 40, pp. 96-101, March
2002.
[Oki02] E. Oki, K. Shiomoto, S. Okamoto, W. Imajuku, and N. Yamanaka,
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A heuristic-based multilayer optimum topology design scheme based on
traffic measurement for IP+Photonic networks," In Proc. of OFC 2002,
3/2002.
[GMPLS-ROUT] "Routing extensions in support of generalized MPLS,
" draft-many-ccamp-gmpls-routing-04.txt (work in progress), 04/02.
[GMPLS-OSPF] "OSPF extensions in support of generalized MPLS,
" draft-ietf-ccamp-ospf-gmpls-extensions-07.txt (work in progress),
05/02.
[LSP-HIER] "LSP hierarchy with MPLS TE," draft-ietf-mpls-
lsp-hierarchy-06.txt (work in progress), 05/02.
[OSPF-TE] "Traffic engineering extensions to OSPF," draft-katz-yeung
-ospf-traffic-06.txt, 10/01.
[ISIS-TE] "IS-IS extensions for Traffic Engineering," draft-ietf-isis
-traffic-04.txt, 08/01.
[GMPLS-SIG] "Generalized MPLS - signaling functional description,"
draft-ietf-mpls-generalized-signaling-08.txt (work in progress), 04/02
7. Author information
Wataru Imajuku
NTT Network Innovation Laboratories
1-1 Hikari-no-oka,
Yokosuka, Kanagawa, 239-0847 Japan
Phone: +81 468 59 4315
Fax: +81 468 59 3396
E-mail: imajyuku@exa.onlab.ntt.co.jp
Eiji Oki
NTT Network Innovation Laboratories
3-9-11 Midori-cho,
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Musashino-shi, Tokyo 180-8585, Japan
Phone: +81 422 59 3441
Fax: +81 422 59 6387
E-mail: oki.eiji@lab.ntt.co.jp
Kohei Shiomoto
NTT Network Innovation Laboratories
3-9-11 Midori-cho,
Musashino-shi, Tokyo 180-8585, Japan
Phone: +81 422 59 4402
Fax: +81 422 59 6387
E-mail: shiomoto.kohei@lab.ntt.co.jp
Satoru Okamoto
NTT Network Innovation Laboratories
1-1 Hikari-no-oka,
Yokosuka, Kanagawa, 239-0847 Japan
Phone: +81 468 59 4315
Fax: +81 468 59 3396
E-mail: okamoto@exa.onlab.ntt.co.jp
Imajuku [Page 17]