Internet DRAFT - draft-ellson-ipo-te-link-provisioning
draft-ellson-ipo-te-link-provisioning
Network Working Group
Internet Draft
Expiration Date: August 2001
John Ellson
Lily Cheng
Lucent Technologies
Admela Jukan
Vienna University of Technology
Anwar Elwalid
Lijun Qian
Lucent Technologies
February 2001
Closed-Loop Automatic Link Provisioning
draft-ellson-ipo-te-link-provisioning-00.txt
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Abstract
Classic IP traffic engineering considers a fixed IP layer topology. In
this draft, we address the limitations imposed by such static network
topology. This work is motivated by introducing dynamically provisioned
links to improve static IP traffic engineering constraints, and
leverage the freedom of provisioning links on demand.
This draft introduces the concept of a closed-loop link provisioning
process for dynamic IP link configuration in an automatically switched
transport network. We identify major phases, which completes an
automatic link-provisioning cycle. First in the traffic engineering
phase, both network internal information and external information can
be applied to proactively or reactively triggering circuit switched
links. Secondly in the network design phase, we distinguish different
types of link design. Finally in the choice phase, we outline a set of
criteria for choosing a final link amongst a set of candidate links.
The criteria are based on maximizing the value of the user network,
where value is computed from: bandwidth, distance, and duration. We
propose these criteria be utilized in studies of dynamic link
provisioning leveraging automatically switched transport networks
(ASTN).
Table of Contents
1. Introduction
1.1 Automatic Link Provisioning
1.2 Terminology
1.3 The Network Model
1.4 The Scope
2. Traffic Engineering: Limitation and Motivation
2.1 Classic IP/MPLS Traffic Engineering
2.2 Limitation of Static Topology of IP/MPLS Traffic Engineering
2.3 Issues of IP over Transport Networks
2.3.1 Bandwidth Mismatch
2.3.2 Time-Scale Mismatch
2.3.3 Cost/Value
2.3.4 Link Availability
3. Closed-Loop Link Provisioning Process
4. Types of Triggering Information and Triggering Mechanism
4.1 Triggering Information
4.2 Triggering Mechanisms
4.3 How They Interact
5. Choosing a Link Type of Candidate Links
6. Performance Measures and Parameters
6.1 Topology-related Performance Measures
6.2 Traffic-related Performance Measures
6.3 Duration-related Performance Measures
6.4 Their Relation
7. Choosing a Link
8. Summary
1. Introduction
1.1 Automatic Link Provisioning
The exponential growth of the Internet coupled with the recent advances
in circuit network technologies has created the opportunity for on-
demand provisioning of wavelength circuits in automatically switched
transport networks (ASTN). This on-demand automatic choice and
configuration of circuits to be used in the IP layer is what we here
refer to as automatic link provisioning. In such a networking scenario,
the fundamental issue is design, ranking, and choice of an IP link,
which is to be established by the circuit-switched layer.
Up to now, much work has been done on the "circuit provisioning" side
of this equation, but very little work has been done on the automatic
design, ranking, and selection on demand of the new IP links.
In this draft, we discuss a closed-loop link provisioning process for
an automatically switched IP over a circuit network such as an circuit
network. We first define the parameters and network traffic information
within the IP network, which relate to the automatic link-provisioning
problem. Based on such information, we will decide on the new IP links
to be established between pairs of routers. We will also give basic
methodologies of choosing among various candidate IP links based on
capacity, distance, and link holding times.
1.2 Terminology
In this draft, the IP link refers to the uni-directional physical
connection between two IP routers. Note that usually IP links are bi-
directional. Any request for a bi-directional link can then be
accomplished by two requests, each for an uni-directional link. We
distinguish between configurable and non-configurable IP links. A
configurable IP link can be dynamically setup and released within the
circuit-switched layer, thus may actively change the IP network
topology.
We also distinguish between two different types of IP router ports,
namely configurable IP router ports and non-configurable IP router
ports. A configurable router port can support a configurable link,
which can be established by using switched circuits; whereas a non-
configurable router port is not capable of dynamic link establishment
in the transport layer. In the limit case, all ports (hence all links)
are dynamically configurable.
1.3 The Network Model
In this draft, we consider a networking scenario, where a number of IP
routers are connected to a circuit-switched transport network, with
which they interact in a user-provider relationship. The topology of
the circuit network is hidden from the client IP network. The circuit
network can be thought of as merely providing dynamically configurable
IP links among the IP/MPLS routers in the client network. Here,
configurability includes the ability to add a link, delete a link, and
modify the parameters of a link.
We consider the IP link establishment within a single IP administrative
domain, hence the choice of the signaling protocol, which will carry
parameters defined in this paper, is not relevant for the time being.
We also further assume that for exchanging and obtaining the network
information as defined here, the only reasonable way of choosing
between multiple demands for links is by co-operation between routers,
which needs new protocol features and standards [newsome00].
In addition, the IP service model as defined by [te-ip-01] with the
Traffic Engineering tool, which triggers a boundary client network
element to issue a link configuration request towards the circuit
domain (either IGP or eEGP peering) can fully support the parameter set
as defined in this draft.
1.4 The Scope
By studying the particular example of the IP network (user) requesting
a new link within a switched circuit network (provider), our technical
approach can apply to a more general issue of any user network type,
not just IP.
The performance parameters of interests for the IP links are only taken
as constraints to the IP link choice. If a circuit connection setup
time is too long with respect to the IP link holding time, the circuit
is not considered for a setup.
In order to address the automatic link-provisioning problem, we will
pursue the following questions:
- What are the limitations of static IP traffic engineering?
- What are the processes involved in automatic IP link provisioning?
- What are the performance measures involved in a IP link choice
problem?
- How to choose amongst candidate IP links?
To answer the above questions, the remainder of this paper is organized
as follows: Section 2 first summarizes current IP traffic engineering
practice and its limitations. It further elaborates the advantages of
IP traffic engineering by considering the automatically switched
transport network. This section serves as our motivation of this work.
Section 3 addresses our work of designing a fundamental link-
provisioning process. Section 4 identifies various information and
mechanisms of triggering a link provisioning request. Section 5
illustrates different link types, which can be chosen as candidate
links, and their affects to the existing network. Section 6 defines
performance measures related to different respects. Such performance
measures can be used to quantify performance improvement of a dynamic
topology. Section 7 outlines basic criteria for choosing a final link
among candidate links. Finally, we summarize this work and give
possible future directions in section 8.
2 Traffic Engineering: Limitations and Motivation
2.1 Classic IP/MPLS Traffic Engineering
In traditional IP/MPLS traffic engineering, the underlying network
topology is assumed to be relatively static [rfc2702, te-MPLS-diff]. In
particular, the links connecting the IP/MPLS routers in the backbone
are typically provisioned for a long period of time due to the
difficulties of rapid reconfiguration of the links.
The main objective of IP/MPLS traffic engineering is efficient mapping
of traffic demands onto the network topology to maximize resource
utilization while meeting QoS constraints such as delay and packet
loss. The traffic demands may be obtained from measurement, projection,
customer prescription, Service Level Agreement (SLA), or combination of
the above. The mapping may be done in a multi-period fashion
corresponding to diurnal or weekly patterns. In a MPLS network, the
mapping is facilitated by establishing explicit label switched paths.
In a connectionless IP network, the mapping can be attempted by
adjusting IGP weights.
Traffic mapping may be performed by a TE tool, which uses the traffic
demand matrix and certain constraints to obtain an optimum solution.
The computation is typically done offline since it often involves
extensive searches on multi-dimensional solution spaces. Alternatively,
traffic mapping may be performed in a distributed fashion, which is
typically determined online. Examples include a computation of
constraint shortest paths between a source and a destination, and load
balancing of traffic among multiple label switched paths between a
source and a destination. More classification is addressed in [te-
frame].
2.2 Limitation of Static Topology of IP/MPLS Traffic Engineering
Observe that the static topology of the IP/MPLS network introduces
limitations. Consider first the case when traffic demands are well
estimated a priori. In this case, provisioning needs to be done
according to the most stringent traffic demand patterns in a given
duration (even under the assumption that the best TE plan, which can
take advantages of multi-period traffic pattern is used). Therefore,
network resources remain under-utilized when traffic demands are light
(e.g., during weekends or evenings) since provisioned links cannot be
released easily.
When the traffic demands cannot be estimated accurately, network
planning may not be done correctly. For example, if link provisioning
is inadequate, traffic demands can exceed the required network
resources. This may occur because of forecasting mismatch or the
inability of provisioning the network fast enough to meet the growth in
resource requirements. On the other hand, it may be necessary to over-
provision the network due to the difficulties of forecasting the
traffic growth accurately.
Furthermore, if the provisioning cycle (i.e., the time it takes to add
resources to the network) is long, resource provisioning needs to take
into account the projected traffic growth until the beginning of the
next cycle. Consequently the extra network resources may be
significantly under-utilized at the early part of a cycle if the
projected growth is large.
These limitations motivate our work that traffic engineering must
incorporate automatic link provisioning for dynamically configurable
circuit networks.
2.3 Issues of IP Over Transport Networks
The problem of automatic link provisioning is more challenging than
traditional static IP traffic engineering. The dynamic nature of the IP
over switched circuit network introduces uncertainties. Some issues are
listed below:
2.3.1 Bandwidth Mismatch
The bandwidth in the IP/MPLS networks is of finer granularity; whereas
the bandwidth in the transport networks is of larger granularity. The
size of an IP link may be in the order of kbps; whereas the size of a
circuit link may be in units of bundled links. Hence, multiple IP links
often have to be tunneled into a link to increase bandwidth
utilization. Such a requirement makes the traffic-engineering problem
one of the optimization problems, which may involve integer
programming.
2.3.2 Time-Scale Mismatch
The holding time of an IP link is usually shorter than the holding time
of an optical link, since an optical link typically contains multiple
IP links. Tearing down one or more IP links may only result in the
reduction of bandwidth in an optical link. Tearing down an optical link
can only be done if all constituent IP links are torn down, or if the
remaining IP links can be re-routed through another optical link.
2.3.3 Cost/Value
Since the establishment of a link incurs a certain cost to the client
IP network, it is important that the cost is within a planned budget.
This may involve re-optimization and tearing down some circuit links.
The circuit network is a limited resource, it is important that the
total value of the links established from a circuit network is
maximized.
2.3.4 Link Availability
A traffic engineering design, which takes advantages of multi-period
traffic demands, requires tearing down and re-establishing links, or
modifying link bandwidth. It is possible that the bandwidth or circuits
that are released may not be available again when a new request
arrives.
Regardless the aforementioned uncertainties, we recognize that
automatic link provisioning is a closed-loop process. Our work is
motivated by introducing this closed-loop process to dynamically
provision links to improve static IP traffic engineering constraints,
and leveraging the freedom of provisioning links on demand.
3. Closed-Loop Link Provisioning Process
This section addresses a closed-loop link provisioning process for
dynamic link configuration in the automatically switched network. A
closed-loop link provisioning process would automatically configure
circuits in the circuit network (Figure 1). We identify several major
phases, which completes an automatic link-provisioning process. They
are traffic engineering, network design, and link choice phases. The
input of this closed-loop provisioning process is the current measure
state of the user network, and the result of the link choice phase is a
target IP link, which can be configured as a switched circuit. The
cycle is closed because changes in bandwidth or topology affect the
state of the user network.
An IP network has network internal information and external
information, that can be applied to proactively or reactively
triggering switched links. Examples of internal information are: packet
loss [rfc2680], router overload, port overload, link overload. Examples
of external information are: SLA violations, or new SLAs. Such
information triggers the network design to automatically configure a IP
link. Depending on the triggering information, configuration can be
adding, deleting circuit links, or modifying existing traffic
parameters.
During the design phase, we distinguish three different types of links,
which will be defined in section 5. The types are predicted by the
information available from the measurements.
Finally in the choice phase, a set of criteria, for choosing a final
link amongst a set of candidate links, is needed. The criteria are
based on the consideration of bandwidth, distance, and duration. The
design phase identifies a set of links that would satisfy some needs;
whereas the choice phase chooses a final set of links based on
maximizing total value.
----------------------------------
the state of the user network
----------------------------|-----
^ | |
| | |
route reactive proactive
updates data data
| | +--------+
| v |
+------------+ +-----------+ |
| traffic | | network | v
+--| engineering|--->-| design |-+ |
| +------------+ +-----------+ | |
| | |
| candidates |
| | |
| +-------------+
| | link choice |
| +-----|-------+
-------------------------- UNI -----------------|-----------
| |
| connection
connection request
result |
| |
| +-------------+ |
+---<-------| configure |---<-----+
+-------------+
^ |
| v
------------------------------------
the state of the provider network
------------------------------------
Figure 1 A Closed-loop Link Provisioning Process
For the on-demand provisioning of a new IP link, to be worth doing, the
IP traffic characteristics must enable a significant sharing of
resources in the provider network. Therefore, it enables a lower cost
service, which can be more attractive to the IP network than a static
topology.
Within the circuit layer a choice between candidate switched circuits
can be made for the IP network in order to have the maximum advantages
of a dynamic configuration. All circuits, which may be configured, are
within the bounds requested by the IP layer, otherwise the request is
rejected. For the remainder of this paper, we will address the tasks of
the three phases in detail.
4. Types of Triggering Information and Triggering Mechanisms
For the traffic information that triggers the establishment of a new
link, we will distinguish between the internal and external
information. Based on either of these information pieces (or both), the
performance measures and parameters of importance for triggering will
be used in a proactive or reactive way (refer to Figure 1).
While we will define the network information sources and triggering
mechanisms for new link request, the protocols and measurements for
their achievement as given in [rfc2679] or [te-frame] will not be
tackled here.
4.1 Triggering Information
The user network contains information, which can be used to trigger a
configuration request. Such information can be either network internal
information or network external information.
Network-Internal Information The internal information deals with the
traffic statistics collected over a certain period of time, based on
which particular traffic flows can be established according to the
predictable traffic patterns. The internal information can also trigger
the reconfiguration of the existing traffic patterns for more efficient
service-level guarantees or network throughput. This information is
reactive but can be also used predictively by assuming cyclic traffic
patterns.
Network-External Information The network-external information deals
with boundary to boundary traffic requests. If such a request
identifies an amount of resources that is needed to predict the need
for circuits. This information can be neither estimated nor measured.
An example of such information might be a new QoS-contract or a new
traffic request with stringent service-level agreements. In this case,
for example, the predictable traffic patterns as defined by the long-
term traffic measurements have to be revised. This information might
come from the new IP network clients or from another administrative
domain such as BGP information.
Both external and internal information may result in similar connection
request, yet they differ in their origin. In the case of the network-
internal information the measures of interests (e.g. packet loss) are
obtained based on the measurements on routers and data collection
within the network. In the case of the network-external information the
needed resources can be estimated based on the service contract
information related to the new traffic.
4.2 Triggering Mechanisms
Proactive information makes possible traffic shaping for particular
purposes, e.g., busy hour, network overload threshold, etc. The
proactive mechanism might also use the bandwidth advertising from the
circuit network in order to pre-estimate the links to establish. The
bandwidth advertising might be invoked periodically.
Reactive information can trigger the establishment of new links upon
measured performance, such as packet loss.
4.3 How They Interact
The triggering mechanisms as previously defined are the timely response
to the network information necessary for a link set-up. The network
failure states are the exemption. A reactive mechanism might trigger a
request for new link upon a failure. Table 1 summarizes their
interaction.
+--------------------+------------------+
| internal | external |
| information | information |
+---------------+--------------------+------------------+
| proactive | busy hour | new SLA |
| information | prediction | |
+---------------+--------------------+------------------+
| reactive | packet loss | |
| information | traffic thresholds | |
+---------------+--------------------+------------------+
Table 1 Interaction of triggering mechanism and triggering information
5. Choosing a Link Type of Candidate Links
A provider network can add or remove links from the user network. We
distinguish three fundamentally different types of links, which can be
constructed in response to IP network demands. As illustrated in Figure
2, there are type1, type2, and type3 links. These three types of new
links differ not only in the number of hops they "bridge" in the IP
layer, but also in the topology changes that occur by adding the new
link. For the remaining of this section, we discuss the various effects
caused by the possible new links.
Type1: A a b c d e Z
O-----O------O------O------O------O------O
* *
********
Type2: A a b c d e Z
O-----O------O------O------O------O------O
* *
***************
Type3: A a b c d e Z
O-----O------O------O------O------O------O
* *
*****************************
Figure 2 Three types of new links: type1, type2, type3.
In Figure 2, consider an IP (user) over an circuit (provider) network,
where traffic flows from the source node A to the destination node Z.
There are three different types of links, which can be configured to
add capacity to this traffic flow.
Type1 The link parallels an existing link, thereby increasing the
capacity of the route but not otherwise changing the topology of the
user network.
Type2 The link is the shortest new link that can be added in some
network path around one node. The Topology of the user network is
modified and routing tables will need to be modified.
Type3 The link is the longest new link, which can be added in some
network between two nodes. The Topology of the user network is modified
and routing tables will need to be modified.
In the above definition, by shortest we mean the minimum reduction in
hop count for a given path, and by longest we mean the maximum
reduction in hop count for a given path.
The distinction between type2 and type3 is subtle. The distinction is
in the reason for adding the new link. The type2 link is the one that
best satisfies the reactive needs to overloads at a single node based
on internal, local-only knowledge of traffic flows; whereas the type3
link is the one that best satisfies the predictive needs identified by
some external contract or SLA for future traffic.
6. Performance Measures and parameters
Each link, which is requested for configuration within the circuit
network will be characterized by its bandwidth, duration, and distance.
We identify performance measures with respect to topology, traffic, and
time. These performance measures can be used to quantify performance
improvement for the automatic link provisioning networks.
6.1 Topology-related Performance Measures
Switched port utilization is defined as the ratio of the numbers of
active ports capable of switching a new link within the circuit network
to the total number of all IP routers ports for automatic switching.
This is a very rough measure of the load distribution over the dynamic
links in the IP network provided by the circuits, since it makes no
assumptions regarding the traffic.
Path length reduction is defined as the ratio of the number of hops
between an IP router pair using automatically switched links
established within the circuit network to the number of hops for the
default routed paths between two routers without new links. For the
path length reduction of a single link, the numerator of this ratio is
1.
This is a direct measure of the number of hops "bridged" by a
dynamically established link. If a link is established between two
neighboring router pairs, then the path length reduction equals one;
otherwise, it is smaller than one. Note that if the number of hops is a
criterion for service accommodation with delay constraints, this will
play an important role. The traffic that traverses a large number of
hops should be favored to use dynamic links.
Path length efficiency is defined as the ratio of the total number of
hops for all IP router pairs using automatically switched circuit links
to the total number of hops for the default routed paths.
This is an indication of the percentage of the number of hops "reduced"
in the network by the automatically established links. For a network
with any switched links of type2 or type3, it is less than one. In this
case, it means that the network only uses up to a certain percentage of
its original links. For a network without any switched links or only
switched links of type1, it is one. In this case, it means that the
network uses the same number of hops with or without the circuit links.
Path length saving ratio is defined as one minus path length
efficiency.
This is an indication of the percentage of the number of hops "saved"
in the network by using the automatically triggered links. If a network
with any switched links of type2 or type3, it is greater than zero. In
this case, it means that the network saves some percentage of hops. If
a network without any switched links or only switched links of type1,
it is zero. In this case, it means that the network doesn't save any
number of hops.
Note that the aforementioned parameters: path length reduction, path
length efficiency, and path length saving ratio are hop-count measures,
which are by no means reflecting actual distance the traffic traveled.
6.2 Traffic-related Performance Measures
Traffic-related performance measures, which is defined below, are more
directly related to bandwidth utilization and network efficiency than
topology measures.
Switched port capacity utilization is defined as the ratio between the
capacity used by an automatically switched link, and the total capacity
available to be used by that link.
Since the capacity of an automatically switched wavelength circuit is
constant and corresponds to the capacity of a channel (wavelength), the
above measure is directly proportional to the encapsulation
(multiplexing) and translation efficiency of the IP-data packet flows
into the circuit channel signals. This measure is related to the
granularity with which the IP traffic is to be reallocated over the
newly established capacity.
Total switched port capacity utilization is defined as the ratio of the
total capacity used by all the switched ports to the total capacity
available to be used by those ports in a switched network.
While switched port capacity utilization indicates the translation
efficiency for each individual automatically switched port, total
switched port capacity utilization shows the efficiency for all
switched ports in the network.
Traffic reallocation efficiency is defined as the ratio of the capacity
taken over by a dynamic wavelength circuit (reallocated capacity) to
the total capacity which has been estimated to be taken over by that
link (overload capacity).
Based on the idea that a dynamically established link is supposed to
accommodate those traffic flows, for which the current network load has
reached a level which triggers the establishment of the circuit links,
this measure refers to the capacity utilization improvement obtained by
this action.
Traffic load ratio is defined as the ratio of the traffic load of an IP
router before and after activation of one or more ports for
automatically switched wavelength circuits.
Packet loss ratio is defined as the ratio of the packet loss of an IP
router before and after activation of one or more ports for
automatically switched wavelength circuits.
6.3 Duration-related Performance Measures
Traffic integration time is defined as the time over which the traffic
is analyzed in order to make a triggering decision for a set-up or
torn-down of an circuit.
Link set-up time is the time it takes the circuit network provider to
set up the requested circuit.
Link service time refers to the user (IP) network and is the duration
that the new circuit is in service.
Link tear-down time is the time it takes the circuit network provider
to tear down the requested circuit.
Link holding time is the sum of the link set up time, link service
time, and link tear down time.
6.4 Their Relation
Generally speaking, topology parameters are of coarse granularities
related to topology changes. Traffic parameters have finer indications
regarding how traffic utilizes bandwidth. Adding or deleting switched
links will affect topology-related parameters. Traffic-related
parameters vary depending on the time instance the performance is
measured.
7. Choosing a Link
The problem of selecting a new link that best satisfies demands for
bandwidth is a multi-dimensional optimization problem, i.e. one that is
mathematically "hard" and probably not possible to compute perfectly,
even in principle. In this paper we are proposing to split the problem
into two parts: link design, and link choice.
Link design provides a set of potential links that could be set up to
meet some traffic need.
Link choice ranks the set of potential links according to value (or
more correctly, rate of return on investment), and then presents the
reduce set of maximum value to the provider circuit network for
implementation. One implication of this is that a Link design may get
refused for reasons of insufficient value, not just because of blocking
in the circuit layer.
The value of any Link is computed from the expected utilization of:
bandwidth*distance*time. Dimensionally: bandwidth is in bits/second,
distance is meters, time is seconds. For any single link the logical
distance in the user's network is just 1 (meter), so the value of a
link is just the number of bits that it is expected
to carry in some interval of time.
The cost of a Link can be computed by the circuit network in a similar
fashion, as: bandwidth*distance*time. The provider calculates using
provided bandwidth rather than utilized bandwidth, and to the provider
the distance is a real contributor to the cost and so is probably
computed in miles or kilometers. None of this matters much since the
result of this expression is multiplied by some factor to give a price,
which is what the user sees. Dimensionally this price can be still
bandwidth*distance*time, or it can be dollars by multiplying by a rate
term. For the purpose of this paper we do not need to consider actual
dollar calculations because the value-price operations (comparisons,
additions, subtractions) can be made dimensionally valid by using terms
that are bandwidth*distance*time.
The price of a Link then can be established when a directory lookup is
performed at the UNI in preparation for possibly requesting a new Link
from the circuit network. Subtracting price from value gives a number
(positive or negative) which can be used to order a set of possible
Link designs and thereby choose the ones that provide maximum return on
investment.
A similar evaluation must be performed on existing links in order to
choose Links, which provide the minimum return on investment and so
should be taken down.
8. Summary
Our paper discusses the limitation of traditional IP traffic
engineering. This work is motivated by introducing dynamically
provisioned links to improve the constraints of existing practices and
leveraging the freedom of setting up and tearing down links on demand.
We approached the fundamental task of dynamic link provisioning by
introducing a closed-loop process.
In the closed-loop link provisioning process, both network internal and
external information can be applied to proactively and reactively
triggering dynamic link setup or teardown. We have concentrated our
work on a set of IP layer performance measures. Associated with the
process of automatic link provisioning, we outlined a set of criteria
for choosing a final link amongst a set of candidate links, which are
based on considerations of bandwidth, distance, and duration. Other
QoS-related parameters, such as delay in IP layer, are not considered
here and are subject to future studies. Automatic link configuration
changes both the network topology and network performance. In order to
leverage the freedom of automatic provision links, such a closed-loop
process is a crucial component of dynamic traffic engineering.
While we have studied the example of the IP network using an
automatically switched transport network, the specific choice of
technologies is not essential to this discussion. As discussed in [te-
ip-01], our work is applicable to any dynamically switched circuits,
which can be any non-packet-switched capable, such as fiber-switched
paths, lambda-switched paths, or TDM-switched circuits.
9. Security Issues
This document raises no new security concerns for MPLS signaling.
10. References
[rfc2702] Awduche D. et. al. "Requirements for Traffic Engineering over
MPLS", RFC2702, September 1999.
[newsome00] Newsome, G. "IP Traffic Engineering resulting in Optical
Layer Connections", IETF draft draft-newsome-mgmtplanerqmts-00.txt,
November 2000.
[te-ip-01] Duroyon O. et. al. "G.LSP Service Model framework in an
optical G-MPLS network", IETF draft, draft-duroyon-te-ip-
optical.01.txt, November 2000.
[te-MPLS-diff] Le Faucheur et. al. "Requirements for support of Diff-
serv-aware MPLS Traffic Engineering", IETF draft, draft-ietf-mpls-diff-
te-reqts-00.txt, November 2000.
[te-frame] Awduche, D. et. al. "A framework for Internet Traffic
Engineering" IETF draft, draft-ietf-tewg-framework-02.txt, July 2000.
[rfc2679] Almes, G. et. al. "A One-way Delay Metric for IPPM," RFC2679,
September 1999.
[rfc2680] Almes, G. et. al. "A One-way Packet Loss Metric for IPPM,"
RFC2680, September 1999.
11. Author Information
John Ellson
Lucent Technologies, Inc.
101 Crawfords Corner Rd
Holmdel, NJ 07733-3030
Email: ellson@lucent.com
Lily Cheng
Lucent Technologies, Inc.
101 Crawfords Corner Rd
Holmdel, NJ 07733-3030
Email: lilycheng@lucent.com
Admela Jukan
Vienna University of Technology
Institute of Communication Networks
Favoritenstrasse 9/388
A-1040 Vienna, Austria
Anwar Elwalid
Bell Laboratories
Lucent Technologies
Murray Hill, NJ 07974, USA
hone: 908 582-7589
Email: anwar@research.bell-labs.com
Lijun Qian
Bell Laboratories
Lucent Technologies
Murray Hill, NJ 07974, USA
Phone: 908 582-4369
Email: ljqian@research.bell-labs.com
