CCAMP Working Group L. Yong
Internet-Draft Y. Lee
Intended status: Informational Huawei USA
Expires: April 21, 2007 October 18, 2006
ASON/GMPLS Extension for Reservation and Time Based Automatic Bandwidth
Service
draft-yong-ccamp-ason-gmpls-autobw-service-00
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Abstract
The draft presents ASON/GMPLS architecture extension for reservation
and time based automatic bandwidth services. It introduces
additional service intelligence function to the control plane. It
describes the service scenarios and procedures for automatic
bandwidth service. It also discusses the potential services enabled
by the service intelligence function.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Conventions used in this document . . . . . . . . . . . . 4
1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
1.3. Acronyms . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Motivation for Reservation and Time Based Automatic
Bandwidth Service . . . . . . . . . . . . . . . . . . . . . . 6
3. ASON/GMPLS Architecture Extension for Reservation and Time
Based Automatic Bandwidth Service . . . . . . . . . . . . . . 10
3.1. Architecture . . . . . . . . . . . . . . . . . . . . . . . 10
3.2. Reservation Service Activation and Deactivation
Procedures . . . . . . . . . . . . . . . . . . . . . . . . 11
3.3. Time Based Automatic Bandwidth Service . . . . . . . . . . 12
3.4. Protocol between Reservation System and Control Plane . . 14
3.5. Time Based Connection Path Management . . . . . . . . . . 14
4. Multi-Layer and Multi-Domain Networks . . . . . . . . . . . . 17
5. Architecture Advantages . . . . . . . . . . . . . . . . . . . 19
6. Other Architecture Solution . . . . . . . . . . . . . . . . . 20
7. Security Considerations . . . . . . . . . . . . . . . . . . . 21
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 22
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 23
10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 24
10.1. Normative References . . . . . . . . . . . . . . . . . . . 24
10.2. Informative References . . . . . . . . . . . . . . . . . . 24
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 25
Intellectual Property and Copyright Statements . . . . . . . . . . 26
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1. Introduction
ASON and GMPLS based architectures have been developed for a long
time in standard bodies. One of objectives is to allow user
instantly request a bandwidth from optical transport networks using
standard protocols. We refer to this model as instant bandwidth
service. The user could be a customer, a client from a different
network layer or from a different administration domain. This model
is adopted from traditional telephony networks, where the network
instantly establishes a connection path when a call request comes and
takes down the connection when the call finishes. Internet
technology boosts the network intelligence capability, which drives a
desire of building the similar intelligence in an optical transport
network and thus enabling an instant bandwidth service in which
connection is instantly provided upon the service request from a
user.
Although the instant bandwidth service is a prevalent mode in ASON/
GMPLS control plane architecture, some dedicate bandwidth services
such as private line are provided based on a reservation. For
example, traditional private line services have been offered in the
way that customer needs to order the service first through an
administrative system, then carrier set up the circuit and work with
the customer to verify the connection paths. Although this service
model is rather rigid and operation intensive, for a permanent
connection and a large bandwidth connection, a carrier still prefers
a way to do reservation and time based bandwidth service. In
addition, some customer may want to reserve the service ahead based
on the future needs and wants the bandwidth to be guaranteed at a
specific time it desires. We refer to this capability as reservation
based automatic bandwidth service through out this document.
Another consideration is that although customer connection could be
dynamic, sometimes the traffic presents a certain pattern as time, as
an alternate solution for the instant bandwidth service, a connection
could be managed as a function of time. We refer to this capability
as time based automatic bandwidth service through out this document.
This document introduces ASON/GMPLS architecture extension to support
reservation and time based automatic bandwidth service. It presents
the application scenarios and service procedures. It also describes
potential new components in a control plane to support the services.
In addition, the comparison between instant bandwidth service and
reservation based bandwidth service is discussed.
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1.1. 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 BCP 14 [RFC2119].
1.2. Terminology
Client Layer: In multi-layer networks, client layer is the layer that
could request a service from the server layer. For example, IP
client layer request a bandwidth from OTN server layer.
Connection Manager: A entity that establish and remove a connection
and maintain all existing connections.
Event Register: A entity that hold all the time related events and
announce an event when its specified time arrives.
Policy Manager: A entity that manage all the policy profiles.
Policy Profile: A entity that gather all the policy rules associated
with a connection or a set of connections.
Policy Rules: A rule associated with a connection. It may relate to
an event or time.
Reservation based automatic bandwidth service: The connection request
could be booked in carrier reservation system ahead of service time.
When the service time arrives, the network could automatically build
up the connection.
Reservation System: A system can book a connection reservation from a
customer.
Server Layer: In multi-layer networks, server layer is the layer that
could provide a service to its client layer.
Time based automatic bandwidth service: The connection path or
bandwidth could be managed as a function of time.
1.3. Acronyms
AIS Alarm Indication Signal
ASON Automatically Switched Optical Network
DOM Day Of a Month
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ENNI External Network to Network Interface.
GMPLS Generalized Multi-protocol Label Switching
HOY Holiday Of a Year
NE Network Element
NMS Network Management System
OTN Optical Transport Network
SDH Synchronous Digital Hierarchy
SONET Synchronous Optical Network
TDM Time Division Multiplexing
TOD Time of a Day
UNEQ-P Unequipped Path
UNI User Network Interface
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2. Motivation for Reservation and Time Based Automatic Bandwidth
Service
IP network success motivates people to develop network intelligence
in an optical transport network. One objective is to enable
automatic connection route selection, connection path establishment
and removal, and connection management in an optical network and
automatic interworking with other layer network such as IP network.
Another objective is to allow user to instantly request a network
bandwidth when it needs. The control plane based network
architecture is defined by both IETF [RFC3945] and ITU-T [ITU-T
G.8080]. Numerous protocols have been developed by IETF since then.
Current instant based bandwidth service model supported in ASON/GMPLS
architecture is shown in Figure 1. The network contains a control
plane and a data plane. A user or client equipment connects to a
network element (node) via physical interface. This interface is
called User Network Interface(UNI) [RFC4208] [ITU-T G.8080]. There
is a signaling channel between a user and the network. When a user
needs a bandwidth from one point to another, it can send a connection
request to the control plane via the signaling channel. The request
will specify the pre-defined network source and destination node
addresses, port IDs, bandwidth, and other service parameters. The
control plane will process the request, select connection route(s) in
the network and build the connection path(s) in the data plane
according the service request. After the user receives the
confirmation message about the connection completion, user could
start data transmission over the data plane. The data stream is then
transmitted along the reserved path toward the destination. Figure 2
show the signaling flows for the connection establishment and data
transmission.[RFC4208] [RFC3473]. When a user completes the
bandwidth usage, it sends a disconnect request to the network, the
network takes down the connection path and releases the bandwidth for
reuse.
Signaling Channel
|
|
__ |-----------------------------| V __
| |-----| Control Plane |-----| |
| | UNI |-----------------------------| UNI | |
|__|=====| Data Plane |=====|__|
User |-----------------------------| A User
| | |
|<--- Network --->| |
|
Physical Interface
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Figure 1: ASON/GMPLS Architecture
Network
User Control Data User
Plane Plane
| | | |
Path +----->|------------------------>|
| | /|
Resv |<-----|<----------------------/ |
|\ | |
ResvConf | \--->|------------------------>|
| | |
Data |<====================>|<=======>|
Transmission| | |
Figure 2: Signaling Flow For Path Establishment and Data Transmission
There are some differences between ASON and GMPLS architecture models
regarding the UNI interface. ASON uses carrier oriented domain
architecture model. UNI is used between user and a network domain;
ENNI is used between two network domains. The ASON control plane
supports service establishment through the automatic provisioning of
end-to-end connection across one or more domains. In contrast, GMPLS
has peer model and overlay model. In the peer model, it assumes a
community of users with mutual trust and shared goals. There are no
inherent policy or security boundaries, and routing and signaling
protocols flow within the network without filtering or other
constraints imposed. In the overlay model [RFC4208], it assumes that
the network nodes act as a closed system, and that user nodes are not
aware of the topology of the network, though network and user nodes
may have a routing protocol interaction for the exchange of
reachability information to other user nodes.
Regardless of the architecture differences in ASON and GMPLS, both
models share the same service characteristics in which the service is
requested at the time the connection needs. In other words, service
request and service time are tightly coupled. This service model may
raise concerns for carriers to offer all the bandwidth services in
optical transport networks in this manner. Here are the major
concerns:
1) It is hard for carriers to predict user demand and guarantee the
dedicated bandwidth when user needs it. Some user may want to book
the bandwidth ahead to ensure the bandwidth availability.
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2) For some Permanent Connection (PC) or a high bandwidth connection,
carriers may want to let a customer book in advance and automatically
provision the connection when service time arrives. This way gives
carriers a chance to plan the network resource ahead of service time
if necessary.
3) Having user directly request the bandwidth from network through
the signaling channel that directly communicates with the optical
control plane could potentially introduce a big security concerns for
carrier. Since the control plane is the network brain, it can not
tolerate any possibility of outsider attack. Thus, the special
security function for the signaling channel at UNI is required.
4) A carrier may not want to expose its network to its customer. To
support UNI, carrier has to define a separated node address, port ID
for customer to use, and the advertisement of customer reachability
in the control plane, which adds the complexity and cost for a
carrier.
5) Some optical data plane takes time to have a path run clean even
the connection path already established from optical control plane.
Therefore, user may get a lot of corrupted payloads initially.
6) The service model presents a big challenge for service operation
and back office system integration.
Today this instant bandwidth service model has been rarely deployed
in a real network although the protocols have been standardized in
the standard body for a while. It is believed due to two major
reasons: 1) most of bandwidth services offered by optical networks
are relatively static and could be reserved ahead of service time; 2)
the service model and its benefits are still under carrier
investigation because of these concerns.
The questions are raised: could ASON/GMPLS architecture support
reservation based automatic bandwidth service? could ASON/GMPLS
architectures support time based automatic bandwidth service as an
alternate solution for bandwidth on demand service. Furthermore, how
could we enhance the control plane to be of service intelligence?
These questions motivate this draft to discuss the possibility of
ASON/GMPLS architecture extension to support reservation and time
based automatic bandwidth services.
* The reservation based automatic bandwidth service is that the
connection service could be booked in carrier reservation system
ahead of service time. When the service time arrives, the network
could automatically build up the connection path.
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* The time based automatic connection is that an existing connection
or bandwidth can be managed as a function of time.
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3. ASON/GMPLS Architecture Extension for Reservation and Time Based
Automatic Bandwidth Service
3.1. Architecture
The great advantage of ASON/GMPLS is to have network intelligence for
network discovery, route selection, path establishment, connection
management. The question is how to utilize the intelligence for a
reservation based bandwidth request. Figure 3 illustrates a possible
architecture model for a reservation based automatic bandwidth
service. In this model, it is assumed that user equipment has been
connected to network with a physical interface such as SONET or
Ethernet; there is no signaling channel between user and network.
The control plane enabled network is able to automatically select a
route and set up the connection path. A reservation system is
provided by a carrier.
+------------+ +---------+
------>|Reservation |<----->| OSS |
Service Request | System | +---------+
+-----+------+
|
|
__ |-------------V---------------| __
| | | Control Plane | | |
| | |-----------------------------| | |
|__|=====| Data Plane |=====|__|
User |-----------------------------| A User
| | |
|<---- Network ---->| |
|
Physical Interface
Figure 3: ASON/GMPLS Architecture Extension
The service Reservation System (RS) allows user to book the service
request ahead of service time. User could specify the service start
time and end time if available, source and destination, bandwidth,
and other service parameters. The RS needs go through the service
validation processes including customer account, connection points,
service quality, etc. To accomplish these steps, the RS needs to
communicate with some back office systems (OSS) such as account,
inventory system. After completing the validation processes, the RS
converts the request to a connection order in a database, and send a
confirmation message back to the customer.
For bandwidth reservation, a provider could use booking information
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in the database to prepare network resource ahead. Since some
services may use the bandwidth over the same network segment in
different time period, they could use the same bandwidth resource at
different time. In TDM network, the bandwidth refers to "timeslot".
Thus, the resource planning is to estimate a bandwidth pool in
network to ensure that all booked services can get the bandwidth at
its service time. If a "special" service really requests to book and
allocate network resource ahead service time, it should be allowed
under some condition such as the ahead period prior to the service
time and/or price.
3.2. Reservation Service Activation and Deactivation Procedures
When the service time arrives, the RS generates a connection request
to the network source node of the connection, the source node will
select route(s) first and then establish the connection path toward
destination node using GMPLS signaling protocol. The signaling flow
for the connection establishment shows in Figure 4. The RS may
provide the explicit route list depending on the implementation, then
the network only needs to establish the connection path.
Although the network already allocates bandwidth for the connection,
user may not generate traffic yet; unequipped path(UNEQ-P)or alarm
indication signal(AIS-P)could be generated by SONET/SDH or OTN data
plane. Thus, the control plane needs to inform the nodes that the
path is in waiting payload period and starts a waiting period timer;
the nodes should not start the path monitor at this time.
Administrative Status Information object in GMPLS signaling may be
used in cooperation on this step. For an advanced situation, the
network could enable an automatic data path verification process
before getting into the waiting period.
Network
User Reservation Control Data User
System Plane Plane
| | | | |
Service +----->| | | |
booking | | | | |
Confirmation |<-----| | | |
~ ~ ~ ~ ~
Request | |----------->| | |
| | | | |
Confirmation | |<-----------| | |
| | |
Data |<============================>|<=======>|
Transmission| | |
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Figure 4: Reservation based RSVP-TE Signaling Flow
When user begins to generate the traffic, both ingress and egress
nodes could detect the payload and inform the control plane. The
control plane at the source node will stop the timer, inform the node
to start monitor the path. The administrative status information
object may be used to inform the connection status.
If the waiting timer is expired, the control plane may take down the
connection path and inform the RS about service cancellation. The
waiting time can be selected by user or a default timer provided by
carrier.
To tear down the connection, there could be two scenarios. First, a
customer does not specify the end time of its connection, it simply
asks network to take down the connection when it stops sending
traffic. Second, a customer specifies the ending time in the service
scheduler system.
In the first scenario, customer stops sending data stream when it
finishes, the nodes at ingress and/or egress detect the payload
missing, the ingress node informs the control plane. The control
plane waits for certain period (configurable or defined in service
profile), then the source node initiates the teardown message toward
the destination node. It will send a service completion message to
the reservation system. The system will go through the service
completion process. It is necessary that the nodes at ingress and
egress differentiate a link or equipment failure from payload missing
and inform the control plane with different status changes.
In the second scenario, the RS sends a disconnection request to the
control plane when the service period expires. The control plane
informs the source and destination nodes to inject UNEQ-P signaling
toward user if the interface is SONET or OTN. Then, the source node
sends a path teardown message toward the destination node and send a
service completion message to the RS. The RS will go through the
service completion process.
The solution suggested here provides an alternate way to
automatically establish a connection path in ASON/GMPLS network.
Once the connection is established, the control plane can manage the
connection based on the service request such as service protection
requirement.
3.3. Time Based Automatic Bandwidth Service
The reservation based automatic bandwidth service solution allows
carrier further implementing event driven service such as a time
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based bandwidth service. A time based service means that the
connection path could be automatically setup, taken down, or modified
based on the pre-scheduled time. For example, a connection will be
setup two hours every day for three months or 600Mbps during the day
and 150Mbps at night. In this case, the reservation system allows
customer to specify time based connection request.
For this advanced application, the RS could convert the reservation
into a connection request associated with a policy profile. When an
initial connection time arrives, it will send a connection request
with the policy profile to the control plane. The control plane will
maintain the policy profile and execute the policy rules specified in
the policy profile. Figure 5 shows some policy rules but not limited
to. How the control plane supports the time based connection request
will be discussed in the section 3.5.
+--------------------------------------------------------+
| Rule Type | Time Duration | Action |
|--------------+-------------------+---------------------|
| TOD | 8AM-5PM | Maintain Connection |
| Time of Day |-------------------+---------------------|
| | Other | Terminate Connection|
|--------------+-------------------+---------------------|
| DOW | M - F | Maintain 600MBW |
| Day of Week |-------------------+---------------------|
| | Sa-Su | Maintain 200MBW |
+--------------+-------------------+---------------------+
Figure 5: Policy Rules
Followings are some potential service features that could be
implemented through the reservation based bandwidth service but not
limited to.
1) Bandwidth service is specified in time pattern, for example, time
of day, day of month, holiday of year, etc. If the connection is
taken down during the break time, it is possible that the new
connection path differs from the old but the service quality remains
the same. The carrier needs to plan the network resource ahead to
ensure the bandwidth availability.
2) Bandwidth modification for an existing connection. Customer
specifies bandwidth variance to the time for a connection. In this
case, the control plane can modify the connection bandwidth without
service disruption.
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3) One reservation for a group of connections among a set of client
ports. The set of client ports could share a same profile. Time
based traffic pattern can be specified among the ports. For example,
there are 10 ports, the first four ports need 200 Mbps and last six
ports need 100 Mbps in day time; two ports need 500Mbps, the rest
needs 50 Mbps at night.
4) Service extension for an existing connection. Customer could
extend the service time through the reservation system.
5) Combined above services. The combined service offers a lot of
flexibility for the bandwidth service. Thus, it may serve as a
bandwidth on demand service.
3.4. Protocol between Reservation System and Control Plane
There are some protocols needed between the reservation system and
the control plane. It is recommended to use existing signaling
protocol, i.e. extend GMPLS signaling protocol to the RS. In this
case, the RS acts as GMPLS signaling agent. The RS can send a
connection request to the source node using GMPLS protocol. Since
the RS and network belong to the same carrier administrative domain,
RS can directly use network internal address and port information in
the connection request. Thus, it is like a user interface in GMPLS
peer model. For the time based service, there will be additional
enhanced objects in GMPLS protocol to carry the time based service
information. Another way to implement is to develop Management
Information Base (MIB) modules between RS and control plane to carry
the connection request information. This implementation requires
control plane to convert MIB into signaling message for an end-to-end
path establishment.
3.5. Time Based Connection Path Management
A control plane is expected to manage a connection in an event driven
policy. For example, when a failure happens [POLICY], it can select
another route for user or allocate the reserved protection path in
shared mesh configuration. To support time based connection
management, the control plane needs to have a time trigger and event
register function.
Figure 6 shows a possible connection controller structure to manage a
scheduled event. There are three components plus a time ticker. The
connection manager(CM) is responsible for connection establishment
and maintenance. The policy manager(PM) manages all the connection
rules. These rules may be associated with an network event and/or
time event. The Event Register(ER) can table all time related events
that will be triggered when the time arrives. When a connection
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request comes from RS, CM in the source node processes the request
and establishes the initial connection by using GMPLS protocol. If
there is a time based policy profile associated with the connection,
CM sends the connection ID and policy profile to PM. PM processes
the policy profile and registers the time based events into the ER.
When an event is on time, EM notifies PM on the event. PM sends the
action with connection ID to CM. Then CM executes the action on the
connection. Such time based function empowers a control plane to
actively manage the connection path. It is possible that a time
based connection may be routed through difference paths during
different connection time but the service quality remains the same.
How to keep a time based connection in the same route needs future
study.
Connection Controller
Connection +----------------------------------+
Request | |
from RS | +------------+ +------------+ |
------------+>| Connection +----> Policy | |
| | Manager <----+ Manager | |
| +------------+ +--A----+----+ |
| | | |
| +-----------+ +-----+----V----+ |
| |Time Ticker|->| Event Register| |
| +-----------+ +---------------+ |
+ ---------------------------------+
Figure 6: Connection Controller Structure
There is a debate whether the time based connection management should
reside in the control plane or management plane, i.e. Network
Management System (NMS). NMS is a centralized system. It responses
to collect fault alarms and performance data from network, provide
equipment configuration and service provisioning, and support all the
operation activities. It is possible to implement time based
connection management function in NMS. In this case, NMS keeps
tracking all connections created by the control plane and maintain
the time based policy profiles. When an event arrives, NMS finds out
the associated connection ID and its source node, then sends the
event to the control plane. The control plane executes the event.
In the model, both control plane and NMS manage the connections. Who
has the connection ownership is questionable. The model may create a
lot of communications between the NMS and control plane for a large
network or frequent connection changes, which could cause a
scalability problem and infrastructure challenge. In contrast, using
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control plane to manage time based connection provides the
distributing management in the control plane and the control plane
fully manages and maintains the connections, which presents some
advantages.
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4. Multi-Layer and Multi-Domain Networks
ASON architecture supports a multi-layer and multi-domain
configuration. [MLN/MRN] The solution described here work for multi-
layer networks as well. Figure 7 illustrates a multi-layer network
in general. Customer equipment physically connect to an ASON network
at client layer, for example, through Ethernet interface, the network
ingress and egress have client layer interfaces; the network side
interfaces have server layer interfaces. The customer could book a
connection request from client layer without knowing the network
topology and architecture at all. When the service time arrives, the
scheduler system will send the connection request to the control
plane, the control plane will select the path route over client layer
adaptation and server layer to establish the connection path. If the
server layer path is already existed, the control plane could also
build a connection path over the existing tunnel in server layer
depending on the service request or control plane policy.
In the similar way, when tearing down a connection, if there are
multiple connections in client layer such as multiple VLANs, client
layer will only tear down the VLAN path in the client layer. When
tearing down the last VLAN path in a tunnel, the control plane could
take down the tunnel as well depending on the service request or
control plane policy.
The reservation based service model allows provider to manage the
server layer connection separately from the client layer connection.
Based on the customer needs, the reservation system could let server
layer to establish a tunnel that connects to ingress and egress at
client layer first. For example, set up a SONET connection and use
GFP at ingress and egress to map to Ethernet port. Thus, when
cusomter wants a P2P connection at Ethernet, the connection can be
built directly over end-to-end client layer through the server layer
tunnel. Multiple P2P connections may be built over a tunnel. As a
result, client layer connections could be very dynamic while a server
layer connection is relative static.
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+------------+ +------+
-------->| Reservation|<--->| OSS |
Service Request | System | +------+
+------------+
|
|
User +--+ | +--+ User
Data Stream ----> =====| | | | |====== Client Layer
..............|..|.......|.......|..|....................
| +-------V-------+ | Server Layer
| |
+---------------------+
Network
Figure 7: Multi-Layer Network
The solution could apply to multi-domain configuration as well. In
this scenario, there could be one reservation system to support
multi-domains or each domain has its own reservation system. If
customer needs to build a connection across multi-domains, it can
book through one system or several systems. A reservation system
will use the same semantics to build connection path through the
control plane. External Network to Network Interface (ENNI) will be
used between domains.
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5. Architecture Advantages
The architecture model for reservation and time based automatic
bandwidth services adopt ASON/GMPLS architecture model and combine
with Web application technology. It de-couples service request time
and service time, which provides a great value for carriers and
customers. It provides a practical architecture to a bandwidth on
demand service in an optical transport network. It has following
advantages compared to UNI based instant bandwidth service.
1.Reservation based automatic bandwidth service can provide better
bandwidth guarantee for the customer. Carrier can observe
reservations and plan the network resources.
2.It does not need a signaling channel between user and network, i.e.
no UNI interface. This simplifies the service model. To support
UNI, carrier has to work out separated node address and port ID for
customer to use, and the advertisement of customer reachability in
the network.
3.Since there is no signaling channel between user and network
control plane, it eliminates the possibility that a control plane is
attacked from UNI signaling channel.
4.This allows network to pre-verify the data plane path by using an
embedded tool or automatically tune a data plane path to ensure the
path running clean.
5.This service model is more close to the private line services that
carrier offer today. It could co-exist with existing ASON/GMPLS
architecture.
6.Advanced reservation system could be designed to offer very
flexible and dynamic service for customers as mentioned above.
7.The architecture model allows carrier easier to implement the
services in term of service operation and back office system support.
Internet technology enables many WEB based reservation applications.
Integrating ASON/GMPLS architecture with the reservation based system
boosts optical control plane capability to support automatic
bandwidth service and open potentials for other advanced services
such as L1VPN and bandwidth trading.
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6. Other Architecture Solution
The architecture solution discussed in this document is one way to
implement the reservation and time based automatic bandwidth service.
The separation between the reservation system and control plane
provides a realistic way for the implementation from many
perspectives. The reservation system can be interwork with other
back office systems to provide customer account management, inventory
verification, resource management, and security management. The
control plane only responses for the connection management.
Another solution is to directly implement reservation and time based
automatic bandwidth service through UNI interface, i.e. enhance the
GMPLS signaling protocol between user and network interface to allow
carrying these time based service information and let control plane
interwork with back office system to perform all the validation
processes and manage the services. Authors think this architecture
design is not a practical design for carrier and it will add more
concerns about the service models over UNI beyond mentioned in this
document.
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7. Security Considerations
This implementation eliminates the security concern at UNI and
requires security management in the scheduler system. Each user
needs to have a private account and security procedure before it can
summit its service request. The architecture presents little
possibility to attack the network.
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8. IANA Considerations
There is no IANA actions requested in this specification.
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9. Acknowledgements
Authors would like to thank James Zhu and Dan Li from Huawei, Adrian
Farrel from olddog, Tomonori TAKEDA and Kensuke SHINDOME from NTT,
and D'Allessandro Alessandro from Telecom Italia for the review and
great suggestions.
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10. References
10.1. Normative References
[ITU-T G.8080]
ITU-T, "Architecture for the Automatically Switched
Optical Network(ASON).", January 2003.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", RFC 2119, March 1997.
[RFC3471] Berger (Editor)et al.,, L., "Generalized MPLS signaling
Functional Description", RFC 3471, January 2003.
[RFC3473] Berger, L., "Generalized MPLS Signaling - RSVP-TE
Extensions", RFC 3473, January 2003.
[RFC3945] Mannie, Ed.,, E., "Gemeralized Multi-Protocol Lable
Switching (GMPLS) Achitecture", RFC 3945, October 2004.
[RFC3946] Mannie, E. and D. Papadimitriou, "Generalized Multi-
Protocol Label Switch (GMPLS) Extension for Synchronoous
Optical Network (SONET) and Sychronous Digital Hierarchy
(SDH) Control", RFC 3946, December 2005.
[RFC4208] Swallow, G., Drake, J., Ishimatsu, H., and Y. Rekhter,
"Generalized Multiprotocl Label Switching (GMPLS) User-
Network Interface (UNI): Resource Rervation Protocol-
Traffic Engineering (RSVP-TE) Support for hte pverlay
model", RFC 4208, October 2005.
10.2. Informative References
[MLN/MRN] Shiomoto, et al., K., "Requirement for GMPLS-based multi-
region and multi-kayer networks", January 2003.
[POLICY] Lee , Y. and Z. James , "Framework for the Polocy-Based
Mechanism in GMPLS Network", May 2006.
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Authors' Addresses
Lucy Yong
Huawei USA
1700 Alma Dr. Suite 100
Plano, TX 75075
Phone: +1 469-229-5387
Email: lucyyong@huawei.com
Young Lee
Huawei USA
1700 Alma Dr. Suite 100
Plano, TX 75075
Phone: +1 469-229-2240
Email: ylee@huawei.com
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