Intent-Based Nemo Problem statement
draft-hares-ibnemo-overview-00
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draft-hares-ibnemo-overview-00
IBNemo BOF S. Hares
Internet-Draft Huawei
Intended status: Standards Track July 5, 2015
Expires: January 6, 2016
Intent-Based Nemo Problem statement
draft-hares-ibnemo-overview-00
Abstract
As IP networks grow more complicated, these networks require a new
interaction mechanism between customers and their networks based on
intent rather than detailed specifics. An intent-based protocol
language is need to enable customers to easily describe their diverse
intent for network connectivity to the network management systems.
This document describes the problem Intent-Based NEtwork Modeling
(IB-Nemo) language is trying to solve, a summary of the use cases
that demonstrate this problem, and a proposed scope of work. Part of
the scope is the validation of the language as a minimal subset.
The IB-NEMO language is a protocol language for interactions between
an application and a network manager/controller. Some would call
this boundary between the application and the network management
system as northbound interface (NBI), and any protocol language that
crosses this as an NBI. IB-Nemo focuses on creating minimal subset
of the total possible Intent-Based desired commands. By creating a
minimal subset (about 20% of the total possible), the IB-Nemo
language can be a simple Intent interface for most applications
(hopefully 80%). Part of validation of this language is to to
determine what data models should result in the network controller
from different use cases. This way as IB-Nemo protocol language is
reduced the effort can verify that the critical information is
stilled passed.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
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time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on January 6, 2016.
Copyright Notice
Copyright (c) 2015 IETF Trust and the persons identified as the
document authors. All rights reserved.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Where to start . . . . . . . . . . . . . . . . . . . . . 3
1.2. FAQ . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.3. Definitions and Acronyms . . . . . . . . . . . . . . . . 7
2. Motivation for Intent Interfaces . . . . . . . . . . . . . . 8
2.1. Challenges in Intent-Based networking . . . . . . . . . . 9
2.2. Roles and User specific network information . . . . . . . 10
2.3. What is a simple Intent-Based Interface? . . . . . . . . 10
2.4. Intent-Based NBI Open Source is heading toward Products . 11
2.5. IB-Nemo Intent NBI is Synergistic to NETCONF and I2RS . . 12
2.6. Rest of Document . . . . . . . . . . . . . . . . . . . . 13
3. Intent-Based NEtwork MOdel (IB-Nemo) Language interface . . . 13
4. Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.1. Inside Scope . . . . . . . . . . . . . . . . . . . . . . 14
4.2. Outside of Scope . . . . . . . . . . . . . . . . . . . . 14
5. Use cases for Intent-Based IB-Nemo . . . . . . . . . . . . . 15
5.1. Virtual Wide-Area Network (WAN) . . . . . . . . . . . . . 15
5.2. Virtual Data Center . . . . . . . . . . . . . . . . . . . 16
5.3. Bandwidth on Demand . . . . . . . . . . . . . . . . . . . 18
5.4. Service Chaining . . . . . . . . . . . . . . . . . . . . 19
6. Gap Analysis and where IB-Nemo Fits . . . . . . . . . . . . . 21
6.1. IETF Working groups Gap Analysis . . . . . . . . . . . . 21
6.2. ODL Open-Source . . . . . . . . . . . . . . . . . . . . . 21
6.3. Open Stack Policy initiatives . . . . . . . . . . . . . . 21
7. From Open Source and IRTF to IETF . . . . . . . . . . . . . . 23
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 23
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9. Security Considerations . . . . . . . . . . . . . . . . . . . 23
10. Informative References . . . . . . . . . . . . . . . . . . . 23
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 24
1. Introduction
This document describes the problem Intent-Based Network MOdeling
(IB-Nemo) language is trying to solve, a summary of the use cases and
a proposed scope of work.
IB-Nemo focuses on a minimal size language to express Intent from an
application to a network management system (or network controller).
Some would describe the interface between the application and a
network as the north bound interface (NBI) from the network manager.
This paper will utilize that term to indicate the point the IB-Nemo
language protocol goes across.
The general idea of "intent-based networking" is that user tells the
network what he wants, but not how to do it. Network provisioning
can then creatively fulfil the users desire. The key challenge is to
provide the user with tools to express what the user wants.
Creation of a minimal size Intent-Based language for Intent requires
boiling down the possible alternative to a minimal subset. It is
like the creators of SQL, boiling down the potential database
commands to a small common subset. The process of creating a minimal
size language requires that the language pass some additional
information for each applications specific context it operates in.
For networking, an example of this additional context may be the name
to address mapping for the nodes the applications wants to connect.
Some data may be additional attributes bound to the role the
application performs. For example, if one of the nodes the
application wants to connect to is a mail-spam cleaner, then
additional attributes may be listed. Another example may be a
"network-nanny" firewall that enforces parental controls. To test
SQL language, the language creators run the commands through a set of
prototypical database models for a set of use cases.
To test IB-Nemo, the working group must select use cases and develop
prototypical data models that should be able to be created in the
network management system by use of the IB-Nemo language.
1.1. Where to start
In the spirit of minimalism, this introduction starts with a 5
question FAQ (frequently asked questions) for those who are familiar
with the concepts of Intent-Based networking to answer "what is
Intent-Based Nemo". If the FAQ answers your questions, jump off to
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the use cases in this document or the [I-D.xia-sdnrg-nemo-language]
along with its management yang modules [I-D.zhou-netmod-intent-nemo].
If you are new to the Intent-Based networking, you'll want to read
through the motivation section before looking at the rest of the
document.
The purpose of this document is simple: to provide others outside the
project with "what, when, where, how, and why" the IB-Nemo network
language should be standardized in the IETF as part of the larger
Intent-Based network effort.
1.2. FAQ
Q1: There are many industry forums working on an Intent-based policy
interface for applications. Why should the IETF form a Working Group
to examine an Intent-Based language?
Over the years industry forums have tried to create a mosaic of
standards groups where each standards group focuses on it's key role.
IETF has focused its efforts on protocols that communicate across the
IP network, and management protocols to manage these efforts.
The Intent-Based Network Modeling (IB-Nemo) language is a language
which communicates between an application and a network management
system that controls traffic through the network. Different forums
may call this network management different names (E.g. SDN
controller or centralized controller or others).
The IB-Nemo language seeks to provide a minimal set of language
statements to pass the intent from an application to the network
management system which is controlling the networks.
Q2: Can Intent North Bound Interfaces (NBIs) control more than
networks?
A user may use Intent language to control storage or CPU cycles, but
an intent-based networking language focuses on networks. Why?
Many operators supporting this work want to control virtual networks,
service-based forwarding in networks or data center networks, home-
networks, and mobile networks. If Intent based networking is
successful, then the community may turn to controlling networks plus
storage plus CPU. The group is starting with what they know.
The [I-D.xia-sdnrg-nemo-language] focuses on three basic components:
logical node, logical link, and a logical data flow.
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Q3: Why a minimal size language? How will you control all of the
network management devices that control the network?
The purpose behind the minimal language set is provide a very simple
language that most applications can use for simple operations. Often
in languages, most users (say 80%)of the language utilize only 20% of
the commands. We'll call this within this paper as the 80/20 rule of
languages. To be available for most applications, the language must
be standardized, interoperate between different implementations, and
have management interfaces.
The IB-Nemo language [I-D.xia-sdnrg-nemo-language] allows groups of
applications to simplify the interface by providing the capability to
transfer a data model that can store common information (e.g. names
or addresses) for nodes and links plus rate of data flow (e.g.
10Gigbit). As an example, an application for a home-network on a
cable network can simply load one set of data from a library and pass
them to the network management system. Applications for virtual
networks for a company could load a different set of data from a
library and send it to the network management system.
The goal of this language is not to support all possible Intent
language commands nor all network management systems. The intent is
to work within the 80/20 rule.
Open-Daylight (ODL) has three Intent-Based Code projects:
o Network Intent Composition (NIC)
(https://wiki.opendaylight.org/view/
Project_Proposals:Network_Intent_Composition) (ODL:NIC),
o Open Daylight Nemo (ODL Nemo) https://wiki.opendaylight.org/view/
NEMO:Main, and
o Group Based Policy (ODL-GBP) (https://wiki.opendaylight.org/view/
Group_Based_Policy_(GBP)).
The ODL-NIC project is creating a Intent based interface that
provides all necessary Intent. The ODL Nemo project is focusing on
creating a minimal size language interface using the 80/20 rule of
languages. The ODL-GBP sees Group-based policy as the automation of
Intent by creating contracts between groups of endpoints.
Q4: Is it time for IETF standardization?
An Open Source release of the Open Daylight code for IB-Nemo (ODL
Nemo)under the Open Daylight Nemo will occur in July of 2015. A
demonstration of this was shown at ONS 2015. The Open Daylight code
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for the Network Intent Composition (ODL-NIC) and the Group Based
Policy (ODL-GBP) was released with the Lithium release in June 2015.
Demonstrations were shown at ONS 2015 of these three source projects.
Both ODL-NIC and ODL-GBP are full-features (aka non-minimal size)
north-bound interface.
The Open Daylight code base has been transitioned to products with a
number of vendors. Some of the ODL source code is headed for the
Open Platform for NFV (OPNFV) project (https://www.opnfv.org). The
IB-Nemo project team is working on the OPNFV Movie project
(https://wiki.opnfv.org/movie) to provide use cases that will allow
matching the ODL code bases with the OPNFV deployments. Much of the
open source code from ODL and OPNFV open source projects has moved
into the product code bases of vendors.
Now is the time for the IETF to begin to standardize the
interoperability of the IB-Nemo interface as the code enters these
open source bases.
Operators in carrier and cable (MSO) see this as a key way to speed
up provisioning by obtaining their users desires via the Intent
Interface. Operators like Telefonica wish to plug IB-Nemo into their
Net-IDE interface.
Q5: What data models will IB-Nemo focus on?
IB-Nemo is focusing on the data modeling that will allow development
of a minimal size language. The process of developing a reduced set
of language commands involves choosing the use cases that must be
solved, and then attempting to design the language to pass the right
information from the application to the network management system.
The best way to validate the language is to have prototypical
application use cases and then use the language to pass the intent
plus the additional contextual information needed in order for the
network management system to create the virtual network needed. A
good way to summarize the information the network management system
stores is in a yang data model. Therefore, the working group scope
includes the creation of these data models to test the language.
Long-term these test cases can be used to test language
implementations.
Like All protocols, IB-Nemo will be created with yang data modules to
configure and manage the protocol. However, these are different than
the modules used to validate the subset of interoperable commands.
These data models are not information models for generic Intent-based
or declarative policy. SUPA is working on generic information models
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for Event-Condition-Action (ECA) and declarative policy. As these
models develop, it is hoped their insights on policy may help those
working in the Intent-based policy.
IB-Nemo work plan does not focus on being an automation architecture
or protocol. ANIMA is working on this in the IETF.
context library
:
+-----------:-----+
| application |
+-------||--------+
|| http with IB-Nemo
|| language
+----------------------------------------+
| network ............. +=======+ |
|management : Nemo : | Nemo | |
| system : Intent ===== Models| |
| : Engine : | for | |
| .............. |content| |
| :yang models : +=======+ |
| :to configure: |
| :Nemo Intent : |
| :Engine : |
+----------------------------------------+
1.3. Definitions and Acronyms
ETSI: European Telecommunications Standards Institute
Intent-Based Interface: An interface which tells what what to do
(go to store) rather than how to do it. (Travel 5 miles down this
road to SAMS Club store)
Intent-Based Language: A intent-based interface consisting of a
protocol that carries a set of Intent commands from the
application to the network management system.
NETCONF: The Network Configuration Protocol
NFV: Network Function Virtualization
ODL: Open Daylight project
ODL NIC: ODL Network Intent Composition
ODL Nemo - ODL Network Intent Nemo
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ODL GBP: Open Daylight Group Based Policy project
ONF: Open Network Forum
RESTCONF:REST-like protocol that provides a programmatic interface
over HTTP for accessing data defined in YANG, using the datastores
defined in NETCONF.
2. Motivation for Intent Interfaces
The IP networks within Carriers, Data Centers, Cloud provider, and
Enterprises continue to grow in size and complexity. Simultaneously,
the services that are demanded by customers, particularly the upper
layer applications, are becoming more and more complicated. The
users of these service demand that the services be available to
mobile devices (E.g. iPADs, smart phones) as well as their desktops.
New applications that demand these services have a short life span
(months rather than years). The current rigid service models are
lacking the flexibility to meet this combination of requirements and
scenarios.
Recent efforts have looked to open source and open APIs for the IP
devices and networks as a way to replace the rigid service models
with fast-paced development. ETSI's NFV group, CableLabs DOCSIS
(docsis.org), and ONF Intent-Based NBI (North-Bound interface) are
industry forums looking at Intent based open APIs. OPNFV Movie
project (https://wiki.opnfv.org/movie) is examining the intent-based
use cases for OPNFV (https://www.opnfv.org/). The use cases in this
document encapsulate many of the use cases discussed with operators
and vendors individually or within these forums.
The idea of Intent-based networking can be summed up in a simple
phrase: "Do not tell me what to do, tell me what you want".
Traditional networking configures devices, network protocols, and
topologies within a network. It is network-device centric. Intent-
based network focuses on the applications (or application workload)
and their interactions. It is application-centric. In Intent-based
networking, the network provisioning or network automation can work
many ways as long as it provides the application the requested
service.
Intent-based network models present the network as the application
would see it. Intent-Based Nemo utilizes the application-centric
view in its modeling of a network. These models may hide details the
application does not need to know.
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2.1. Challenges in Intent-Based networking
The challenges in Intent based networking are to:
1. create a common definition of intent,
2. create a common architecture of a Interoperable Intent-Based
Northbound API,
3. create a standard and interoperable way for the applications to
communicate with the network, and
4. create a way to reduce the complexity that the context places on
the intent engine.
The ODL projects, the Distributed Management Task Force (DMTF -
www.dmtf.org), Open Networking Foundation (ONF) Intent-Based
Northbound interface(NBI) working group (ONF Intent NBI WG)
(https://www.opennetworking.org/technical-communities/areas/
services/1916-northbound-interfaces), and OpenStack Congress
(https://wiki.openstack.org/wiki/Congress) are working on definitions
of Intent.
The IETF SUPA BOF (http://tools.ietf.org/bof/trac/) proposes to
create IETF Working group which will create a generic declarative
information policy model as well as a generic Event-Condition-Action
(ECA) policy model. The authors of the SUPA BOF policy drafts are
familiar with the DMTF work, the ONF NBI WG effort, and the OpenStack
Congress model.
ONF Intent NBI WG (http://www.onfsdninterfaces.org/) and ODL-NIC
project are working on common architecture principles for the Intent-
Based Northbound API (https://wiki.opendaylight.org/view/
Network_Intent_Composition:Main) with work to define application end
points (https://wiki.opendaylight.org/view/
Network_Intent_Composition:Dynamic_Attributes).
IB-Nemo seeks to simply apply this evolving work by creating an
interoperable minimal size language operating as a protocol between
the application and the network management system (or network
controller). The IB-Nemo language interface reduces the complexity
of the full intent-based NBI (northbound interface) by supporting a
portion of the commands most often used. The people on the ODL Nemo
project https://wiki.opendaylight.org/view/NEMO:Main. have selected
a small set of commands and created an open-source prototype. The
IETF work is to review and standardize the set of commands to make
sure it provides an interoperable set for all applications.
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2.2. Roles and User specific network information
Authentication, Authorization and Accounting (AAA) protocols such as
Diameter and Radius pass information on the access permissions that
certain users or user programs have to a network or virtual network.
Group based policy suggests that a group of users may share a set of
policy that determines the access to the network or a virtual
network. Role-based network access suggests that roles can better
summarize what access the user or user programs have to the network.
Since IB-Nemo is trying to use prototypical use cases to test the
ability of the IB-Nemo language to pass enough information to create
the appropriate data models in the network management system, it is
natural to use the role-based concepts of summarization to describe
these data models.
The contextual information is the characteristics which make groups
of applications unique when operating over the network. Logically
most of this information may be associated with roles. For example,
if you have a set of users in a home communicating over a home
network the characteristics which are unique is a set names and
address for devices, links, and policy within the home. If it is a
virtual network for a company, the unique information the names,
addresses, links, and bandwidth expected on the links along with
security issues. As these examples show, Intent networking can be
seen to be a few prototypical application-centric network topologies
plus a set of unique information (which could be called context).
Both the home network and the virtual network are creating a virtual
network for the applications running over the network.
2.3. What is a simple Intent-Based Interface?
What is a simple interface? It is said that 80% of the applications
only use 20% of the commands in any open API. This paper calls this
the 80/20 rule of networking. A simple Intent-based interface only
supports these 20% of the total Intent-Based commands in a north
bound interface (NBI). The challenge in any Intent-based interface
is to create a simple interface that serves 80% of the applications
that is easy to use and similar to a human being's natural language.
The challenge is that different industries may have a different 20%
of the commands that are commonly used. The Nemo Project teams in
the ODL Nemo project and OPNFV Movie project are seeking uses cases
to determine if there is common set of use cases that vary just by
context. For example, a global L3VPN for a company with three sites
may be similar to a three site L3VPN across a cable network.
After getting a set of uses cases, creating a simple interface is the
four step repetitive process:
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1. find use cases,
2. develop prototype code,
3. do early testing at proof of concept demonstrations and hack-
a-thons
4. work with many vendors to clarify language to make the language
small and interoperable, and
5. go back to step 1
Where is Nemo is this process?
IB-Nemo has gone through steps 1-3. Use cases are listed below, and
the OPNFV project is working on use cases. IB-Nemo's ODL Nemo
project is developing the code for the open source (ETA July
release). IB-Nemo is at a stage where it needs to work in a
standards body to create a small, efficient, interoperable protocol
language.
The standardization through an IETF WG will help IB-Nemo to work on
step 4.
2.4. Intent-Based NBI Open Source is heading toward Products
The following are Open Daylight Projects:
Open Daylight Group Based Policy (GBP)
https://wiki.opendaylight.org/view/Group_Based_Policy_(GBP)
OpenDaylight Network Intent Composition (ODL-NIC)
(https://wiki.opendaylight.org/view/
Project_Proposals:Network_Intent_Composition), and
Open Daylight Network Intent Composition: Nemo
https://wiki.opendaylight.org/view/NEMO:Main.
These are open-source coding efforts creating an intent-based
northbound interface for intent-based networking.
The ODL Group Based Policy (GBP) views policy as a contract between
two endpoints, and sees its work as the automation of Intent.
ODL-GBP was released in the ODL Lithium release in June of 2015.
The ODL-NIC project is creating a Northbound interface (NBI) for
network orchestration systems, SDN applications, and Network
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operators. It may be defined as RESTCONF [I-D.ietf-netconf-restconf]
protocol and/or Java APIs. This extensible interface will be
designed to allow any and all new intent expressions to be exposed as
part of a consistent and integrated single NBI to SDN applications.
The singularity is necessary for the Composition Function to provide
a comprehensive capability to manage network resources and resolve
conflicts across application's intents. In a sense, the ODL-NIC
project is suggesting a thin waist of a single API at the entrance to
the networking layer, just as the IP protocol presents a thin waist
of a single API at network layer.
ODL NIC project was released in June of 2015.
The ODL Nemo project has created a minimal language interface as part
of this effort that funnels all new intent expressions into a
consistent and integrated single NBI for SDN applications. The
original language has 15 language statements in three groups. Group
1 describes nodes, links, and flows between nodes. Group 2 deals
with operational checks (query, notification, policy, connect,
disconnect, session (start), and commit (end of commands). Group 3
defines the model that provides the context for nodes, links, flows
and policy.
ODL Nemo project is due to be released in July of 2015
ODL open source code is currently finding its way rapidly into other
sources (E.g. OPNFV code base) and into products that are within 6
months to a year of release.
2.5. IB-Nemo Intent NBI is Synergistic to NETCONF and I2RS
The IETF netconf [RFC6541] and restconf [I-D.ietf-netconf-restconf]
protocols provide a network interface to the configuration and status
information within IP network devices. The IETF I2RS (Interface to
Routing System) WG is creating a highly dynamic network interface to
the routing system which can inject or retrieve state regarding
routing state, topologies, filters, and operational state. The PCE
Working Group has protocols and methods to pass routing for
calculation. Each of these interfaces and protocols have a purpose
in managing and enhancing IP network infrastructures.
Intent Based NBI is synergistic to these IETF interfaces to the
devices. Synergistic means that sum of Intent Based Nemo language +
NETCONF + RESTCONF + I2RS + PCE is more than any of the parts alone.
Intent Based Nemo language can signal from the application/user to a
central client which configures, manages, and monitors network
devices through these protocols.
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2.6. Rest of Document
Based on this motivation, the next sections discuss:
o What is Intent-Based NEMO Language Interface?
o The Scope should the Intent-Based NBI work
o Summary of Use cases for this scope
o Gap Analysis and where IB-Nemo fits
o Transition from IRTF to IETF
3. Intent-Based NEtwork MOdel (IB-Nemo) Language interface
A protocol based on language best resembles a natural language. To
determine what form the language should take, the authors of
[I-D.xia-sdnrg-service-description-language] analyzed customer
technical requirements to determine the design considerations for
such a language. They conclude that an intent-based language should
have the following abilities for virtual network devices:
o Be able to describe customer traffic which can be identified as
flows,
o Be able to describe access nodes, virtual networks, servers, and
other network entities as the end-customer perceives these
devices;
o Be able to describe QoS, SLAs, and other relevant properties;
o Be able to describe logic that combines a few demands together
with certain choices for specific circumstances;
o Be able to describe the network so the network customers can
describe their demands; and
o Be able to be extended.
The Open-Daylight Network Intent Composition project
(https://wiki.opendaylight.org/view/Network_Intent_Composition:Main)
has begun an open-source project for a North-Bound Interface (API)
from orchestrator to controllers that provides abstracted policy
syntax rather than open-flow rules.
The Affinity chaining proposal
(https://wiki.opendaylight.org/images/3/30/
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Affinity_Service_Chaining_Proposal_ODP_7-23-2013.pdf) suggests
structure similar to IB-Nemo's structure (node, links with end-
points, and flows). This open-source project has suggested
requirements similar to requirements noted by
[I-D.xia-sdnrg-service-description-language].
4. Scope
4.1. Inside Scope
The initial scope of this IB-Nemo work has focused on:
1. creating minimal size language for north bound interface for
Intent-Based Networking with a modelling mechanism that handles
user context,
2. selecting use cases and associating them with prototype
applications in order to determine the subset of commands that
needs to be included in IB-Nemo language,
3. validating the IB-Nemo language by creating data models (which
should exist in the network management system) for each
application use case to determine if the language can help a
network management system create the right data model
4. creating a management data model to manage this Intent-Based
Networking language, and
5. working with other forums to refine a definition of intent so
that the minimal size language serves a wide range of use cases
(target of 80% of known use cases) with an interoperable
interface.
4.2. Outside of Scope
The following things are outside the IB-Nemo scope:
o The creation virtual networks using I2RS or netconf/restconf to
directly connect to a yang model is outside the the scope of the
proposed IB-Nemo work.
o The creation of a service-layer interface using I2RS and yang data
models is outside the scope of the proposed IB-Nemo work.
o The creation of a language to communicate from a security network
management system to the network security devices is outside this
scope.
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5. Use cases for Intent-Based IB-Nemo
The following use cases are described in this section:
1. Virtual WAN
2. Virtual Data Center
3. Bandwidth on Demand
4. Service Chaining
5.1. Virtual Wide-Area Network (WAN)
Description: Enterprises want to set up their own virtual WAN for
more control and optimization.
User Intent: Create virtual Wide-Area network between offices.
Network management systems do the following:
1. Deploy virtual routers and links for a customized topology.
2. Identify flows.
3. Steer flows though different path. (E.g. real-time flow to go
through a shortest path, and backup flow to go though a broadband
path but may have more hops.)
The network management data system should have a data model that
captures this information. IB-Nemo needs to pass this information in
the IB-Nemo language.
Network operator: Creates web portal for business customers to
request a WAN connecting offices. Interface request corporate ID,
security ID, and a link to the payment system.
The sub-cases of this general use are the following.
Home LAN attached to Corporate Network
parental controls for child travelling outside the home
Details can be found in (draft-hares-nemo-usecases-00.txt)
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==== real time (R1-)
**** broadband
....................
: Virtual LAN :
: (real time path) :
: :
+-------+ : (real time path) : +---------+
| =========================== |
| | : e f : | |
|Beijing|-----R1- - - - - R2---| London |
|office | ***a|* \b c / | d : | office |
+-------+ : | * \ / |****>+---------+
: | * \ / |* :
: | / \* |* :
: | / \* |* :
: | / \*|* :
: R4- - - - R3 :
....................
Figure 5-1:
5.2. Virtual Data Center
Description: User (corporate or home) creates a virtual data center
with network. The virtual data center has a front-end network of
router to exterior firewall to DMZ LAN to interior firewall to
computing user.
User Intent: Corporation wants to buy want to buy Cloud computing
inside a virtual data center with secure computer cluster.
Network Operator service provider: Defines secure cluster network as
the following network topology:
o router connected to network,
o exterior firewall,
o DMZ LAN,
o interior firewall,
o interior secure LAN with compute clusters.
The network management system must have a data model with this
information. IB-Nemo must pass this information to the network
management system.
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Network Operator:Creates Web portal for business customers to put in
request with corporate ID and level of security for cloud cluster.
User will have to provide corporate accounting and security IDs.
Context: Corporate context puts in the amount of computing power and
the virtual topology for security. The template of Secure vDC will
be set-up with router, exterior firewall, DMZ, interior firewall,
LAN. Both the Corporate context and the secure vDC context will be
loaded into the customer's context for processing.
Operator automation: Based on the context with Intent, corporate
context, secure vDC context, the operator automation series will
place the virtual cluster in a data center, and set-up the vDC and
the Cloud computer clusters. The Corporate customer IDs that are
pushing data to this vDC will have the vDC defined in the Corporate
culture.
Specific use cases from this prototypical use case are:
o User gets clean mail services with firewall and spam mail cleaner
o SMB Manufacturing network with Virtual DataCenter
o SMB with Sales-Marketing accounting on Virtual Data Center
These are described in (draft-hares-nemo-usecases-00.txt)
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(internet )
|
..........|...................
+-----|------+
| router |
+-----|------+
|
+-----|------+
| firewall |
| exterior |
+-----|------+
|
===============
DMZ |
+-----|-------+
| firewall |
| interior |
+-----|-------+
|
( protected )
( cloud )
Figure 5-2
5.3. Bandwidth on Demand
Description: The corporate user wants to create a virtual link
between remote offices and headquarters that has bandwidth that can
be adjusted based on time of day.
User Intent:Corporation wants to connect branch office with corporate
office with 10G of bandwidth for data flow 8am to 6pm, and 1G of
bandwidth from 6pm to 8am.
User interface: A web portal allows him to login (corporate ID and
security IDs) and indicate this intent via a graphic picture of his
network that allows him to indicate on-demand bandwidth size and time
of day.
Network Operator:Creates Web portal for business customers to put in
request with corporate ID and level of security for entrance into the
corporate intent site. The Web portal allows for prototypical use
case (virtual WAN, Virtual DC, Bandwidth-on-demand Virtual Private
Network (VPN), Service Function Chaining (SFC). The network
operators store enough application-level topology that the the users
intent is defined.
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Operator automation: Based on the data passed by Nemo providing the
Intent and the data regarding the corporate virtual data center, the
provisioning software will automatically will allocate bandwidth
between these two sites at the rate indicated. The access router/
switch can optionally limit at a rate over this value.
Corporate Virtual Data Center information: includes the IP address,
DNS names, and application addresses (Transport Ports, application
identifiers) of subnet with application works on, and the
applications transferring data. The corporate data also includes
information on whether L2VPN or L3VPN is used by the customer.
==== 8am to 6pm 10GB
**** 6pm to 8am 1BG
....................
: VPN :
: :
+-------+ : daytime : +---------+
| =========================== |
| | : e f : | |
|Branch |-----R1- - - - - R2---| HQ |
|office | ***a|* \b c / | d : | site |
+-------+ : | * \ / |****>+---------+
: | * \ / |* :
: | / \* |* :
: | / \* |* night time
: | / \*|* :
: R4- - - - R3 :
....................
Figure 5-3:
The following use cases are specific examples of this prototype use
case:
Home Network gaming system
Home Security system zoom-in
Application Big Data or SAP Transfers at night
Database applications contact other database applications
5.4. Service Chaining
Description: Apply several virtual network functions, such as
firewall, load balancer, WAN optimization between virtual private
cloud and the internet.
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User Intent: User has a private cloud and wants to get a secure
interface to the Internet.
Network Operator network management system defines the secure access
ring of protection around the private cloud to be the following
virtual network topology:
o firewall
o load balance
o DPI inspection
Network Operator:Creates Web portal for business customers to put in
request with corporate ID and level of by clicking a request.
Corporate Information: Corporate context has the topology of private
cloud, and the access points. The network operator will access
service chaining to through a virtual access ring.
Operator automation: Based on the context of the network topology of
the private cloud's link to the carrier network and the access points
to service chains, the network automation sets up the traffic flow so
that the traffic to and from the private cloud flows through a
firewall, load balancer, and DPI inspection.
(internet )
|
..........|...................
+-----|------+
| firewall |
|--| function |--------|
| +-----|------+ |
| | |
| +-----|---------+ |
| | load balancer | |
| | function | |
| +-----|-------|-+ |
| | | |
| +---|-+ +---|--+ |
+----|DPI 1| |DPI 2 |----+
+---|-+ +---|--+
| |
( private Cloud )
( for corporation )
Figure 5-4
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The specific use cases for this prototype are:
Providers access edge box replaced by service chaining for wired
and wireless (LTE and Wifi)
Corporate access edge box replaced by service chaining for wired
and wireless
Wifi offload of LTE does service chaining to replace mobile
services
6. Gap Analysis and where IB-Nemo Fits
6.1. IETF Working groups Gap Analysis
No working group is working on an Intent-Based NBI.
SUPA proposes to create an information model for generic and intent-
based policy. IB-Nemo will use this generic intent-based policy to
help guide their creation of the minimal size intent based NBI.
NETCONF and NETMOD are not creating an intent-based interface.
6.2. ODL Open-Source
ODL network intent composition (ODL-NIC) is creating a full intent-
based North Bound Interface. ODL Nemo is creating a minimal size NBI
(20% of command that serve 80% of applications) in open source. The
IETF IB-Nemo work will create an interoperable protocol based on the
IB-Nemo language with its context models.
OPNFV Movie project (https://wiki.opnfv.org/movie) is defining the
use cases for Intent-Based networking. IETF IB-Nemo will expand on
these use cases, and exchange information beyond just the Network
Function Virtualization into Cable networks (MSO) or carrier
networks.
6.3. Open Stack Policy initiatives
None of the Open Stack Congress work focuses on Intent networking or
intent-based policy.
Open Stacks policy includes network, compute, and storage. Its work
combines automation (scheduling of resources, monitoring cloud
services, Event-Condition-Action (ECA) policy, ECA based management),
store-related policy, and meta-data policy storage. The projects
are:
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OpenStack has Congress (https://wiki.openstack.org/wiki/Congress)
with its Congress initiative aims to provide an extensible open-
source framework for governance and regulatory compliance across
any cloud services (e.g. application, network, compute and
storage) within a dynamic infrastructure.
SolverScheduler (Nova blueprint): The SolverScheduler provides an
interface for using different constraint solvers to solve
placement problems for Nova. Depending on how it is applied, it
could be used for initial provisioning, re-balancing loads, or
both.
Gantt: A scheduler framework for use by different OpenStack
components. Used to be a subgroup of Nova and focused on
scheduling VMs based on resource utilization. Includes plugin
framework for making arbitrary metrics available to the scheduler.
Neutron policy group: This group aims to add a policy API to
Neutron, where tenants express policy between groups of networks
and ports. Policy statements are of the form "for every network
flow between groups A and B that satisfies these conditions, apply
a constraint on that flow". Constraints are currently are allow
or deny, but this may expand.
Open Attestation: This project provides an SDK for verifying host
integrity. It provides some policy-based management capabilities,
though documentation is limited.
Policy-based Scheduling Module (Nova blueprint): This effort aims
to schedule Nova resources per client, per cluster of resources,
and per context (e.g. overload, time, etc.).
Tetris: This effort provides condition-action policies (Event-
Condition-Action policy). It is intended to be a generic
condition-action engine handling complex actions and optimization.
This effort subsumes the Runtime Policies blueprint within Nova.
It also appears to subsume the Neat effort. Tetris and Congress
have recently decided merge because of their highly aligned goals
and approaches.
Convergence Engine (Heat): This effort separates the ideas of
desired state and observed state for the objects Heat manages.
The Convergence Engine will detect when the desired state and
observed state differ and take action to eliminate those
differences.
Swift Storage Policies: A Swift storage policy describes a virtual
storage system that Swift implements with physical devices. Today
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each policy dictates how many partitions the storage system has,
how many replicas of each object it should maintain, and the
minimum amount of time before a partition can be moved to a
different physical location since the last time it was moved.
Graffiti: Graffiti aims to store and query (hierarchical) metadata
about OpenStack objects, e.g. tagging a Glance image with the
software installed on that image. Currently, the team is working
within other OpenStack projects to add user interfaces for people
to create and query metadata and to store that metadata within the
project's database. This project is about creating metadata,
which could be useful for writing business policies, not about
policies over that metadata.
7. From Open Source and IRTF to IETF
As discussed above, the open-source work for ODL-NIC had its first
release in June of 2015 and ODL Nemo plans its first release in July
of 2015. The movement of these code sources to OPNFV
(https://www.opnfv.org/) will happen rapidly, aided by the OPNFV
Movie project (https://wiki.opnfv.org/movie) use case work. In order
to get an interoperable minimal size (80/20 rule) IB-Nemo language,
it is important to standardize the language in IETF. As part of the
standardizing of the language, the work also needs to standardize
Yang modules to configure the Intent-Based Engine plus Yang modules
for the storage of Context specific data (see figure x-x).
Initial concepts for IB-Nemo have been presented in IRTF's NFVrg and
SDNrg to obtain initial review.
8. IANA Considerations
This draft includes no request to IANA.
9. Security Considerations
The security in a Intent-Based interface may require that most
Intent-Based Networking operate across a secure transport security
with encryption. However, some use cases (in-home only) or some
limited data may allow an unsecured transport.
10. Informative References
[I-D.ietf-netconf-restconf]
Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
Protocol", draft-ietf-netconf-restconf-06 (work in
progress), June 2015.
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[I-D.xia-sdnrg-nemo-language]
Xia, Y., Jiang, S., Zhou, T., and S. Hares, "NEMO (NEtwork
MOdeling) Language", draft-xia-sdnrg-nemo-language-02
(work in progress), May 2015.
[I-D.xia-sdnrg-service-description-language]
Xia, Y., Jiang, S., and S. Hares, "Requirements for a
Service Description Language and Design Considerations",
draft-xia-sdnrg-service-description-language-02 (work in
progress), May 2015.
[I-D.zhou-netmod-intent-nemo]
Zhou, T., Liu, S., Xia, Y., and S. Jiang, "YANG Data
Models for Intent-based NEtwork MOdel", draft-zhou-netmod-
intent-nemo-00 (work in progress), February 2015.
[RFC6541] Kucherawy, M., "DomainKeys Identified Mail (DKIM)
Authorized Third-Party Signatures", RFC 6541, February
2012.
Author's Address
Susan Hares
Huawei
7453 Hickory Hill
Saline, MI 48176
USA
Email: shares@ndzh.com
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