I2RS overlay use case
draft-hu-i2rs-overlay-use-case-00
This document is an Internet-Draft (I-D).
Anyone may submit an I-D to the IETF.
This I-D is not endorsed by the IETF and has no formal standing in the
IETF standards process.
The information below is for an old version of the document.
| Document | Type |
This is an older version of an Internet-Draft whose latest revision state is "Expired".
|
|
|---|---|---|---|
| Authors | fangwei hu , Bhumip Khasnabish | ||
| Last updated | 2013-03-11 | ||
| RFC stream | (None) | ||
| Formats | |||
| Stream | Stream state | (No stream defined) | |
| Consensus boilerplate | Unknown | ||
| RFC Editor Note | (None) | ||
| IESG | IESG state | I-D Exists | |
| Telechat date | (None) | ||
| Responsible AD | (None) | ||
| Send notices to | (None) |
draft-hu-i2rs-overlay-use-case-00
Network Working Group Fangwei. Hu
Internet-Draft ZTE
Intended status: Standards Track Bhumip. Khasnabish
Expires: September 2, 2013 ZTE USA Inc.
Mar 2013
I2RS overlay use case
draft-hu-i2rs-overlay-use-case-00.txt
Abstract
This document proposes an overlay network use case. The forwarding
routers network is an overlay structure. There are two kinds of
forwarding routers: Edge Router(ER) and Core Routers(CR). Edge
Router encapsulates format data based on the tunnel type, which are
established among Edge Routers. Core Router would be very simple and
cheap. It focus on the encapsulation data forwarding. In order to
reduce the equipment cost of Edge Routers, the network virtualization
is provided in this document.
Status of this Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
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 September 2, 2013.
Copyright Notice
Copyright (c) 2013 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
Hu & Khasnabish Expires September 2, 2013 [Page 1]
Internet-Draft I2RS Overlay Mar 2013
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Overlay Network Structure . . . . . . . . . . . . . . . . . . . 3
2.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.2. The Benefit of Overlay Network Structure . . . . . . . . . 5
2.3. Core Router Requirements . . . . . . . . . . . . . . . . . 5
2.4. Edge Router Requirement . . . . . . . . . . . . . . . . . . 5
3. Network Virtualization(NV) . . . . . . . . . . . . . . . . . . 6
3.1. Benefits of Network Virtualization . . . . . . . . . . . . 6
3.2. Applications and Requirements . . . . . . . . . . . . . . . 6
3.3. Network Virtualization . . . . . . . . . . . . . . . . . . 7
4. Security Considerations . . . . . . . . . . . . . . . . . . . . 8
5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 8
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 8
7. Normative References . . . . . . . . . . . . . . . . . . . . . 9
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 9
Hu & Khasnabish Expires September 2, 2013 [Page 2]
Internet-Draft I2RS Overlay Mar 2013
1. Introduction
As modern networks grow in scale and complexity, the need for rapid
and dynamic control increases. I2RS([I2RS-FRM]) provide a new
routing system framework to meet the requirement. There is a
programmable interface for the forwarding router. All the forwarding
routers should support I2RS agent to communicate with controllers.
The forwarding routers gather the traffic and topology information,
report to the controllers, and receive the policy from controllers.
Besides the idea of programmable and open interface, another key
feature is forwarding plane and control plane separation in the I2RS
and software define network. Some of the control and computing
function could be separation from traditional routers. By this way,
we hope that the service and data encapsulation are all done in the
routers of the edge of network, and the routers in the core part are
only focus on data forwarding. The core routers RIB table could only
store the network(or equipment) IP prefix, and does not store user(or
end station) IP prefix anymore. The RIB and FIB table capability of
core routers would be reduced significantly, and the equipment cost
could be lower. The full mesh tunnel is required for the edge
Routers. This is actually an overlay network structure. The
forwarding routers in the overlay network are divides into two kinds
based on the roles in the network: CR(Core Router) and ER(Edge
Router).The Edge Routers encapsulate the forwarding data based on the
tunnel type, gather topology information, and report traffic to the
controller, while Core Routers focus on fast data forwarding and
receive only policy related information(metadata)from the controller.
2. Overlay Network Structure
Hu & Khasnabish Expires September 2, 2013 [Page 3]
Internet-Draft I2RS Overlay Mar 2013
2.1. Overview
+--------+ +--------+
| Edge +--+ +---| Edge |
| Router | | | | Router |
+--------+ | | +--------+
| +------+ +------+ |
| | Core | |Core | |
+--|Router|---------- |Router|-+
+------+ +------+
/ \
/ \
+--------+ / physical topology \ +--------+
| Edge |--+ +----| Edge |
| Router | | Router |
+--------+ +--------+
===================================================================
+--------+ +--------+
| Edge |--+ +----| Edge |
| Router | | | | Router |
+--------+ | ................... | +--------+
| . . |
| . * * . |
+----. * * .-----+
/. * * .
/ . * * .
/ .Overlay * Tunnel .
+--------+ / . * * .-----+ +--------+
| Edge +--+ . * * . | | Edge |
| Router | . * * . +----| Router |
+--------+ ...*............*.. +--------+
Logical Tunnel
Figure 1 Overlay Structure
The overlay structure is shown in Figure 1. The upper half part of
the Figure show a physical network. The Edge Routers are located in
the edge of the overlay network, and are logically connected through
Core Routers.The services and data encapsulation are done in the edge
routers. The Core Routers are very simple; and focus on the data
forwarding, and may not perceive any distinction among the tunnels
to/from Edge Routers.
The lower half of the Figure shows a logical tunnel network. All the
Edge Routers are connected via a logical-full mesh tunnel-based
connection among them. The tunnel could be IP/MPLS/OTN tunnel. Edge
Router encapsulates/decapsulates the data based on the tunnel type.
If tunnel type is IP network, the encapsulation format would be IP
Hu & Khasnabish Expires September 2, 2013 [Page 4]
Internet-Draft I2RS Overlay Mar 2013
over GRE, or IP over UDP. If tunnel is MPLS network, the
encapsulation format is IP over MPLS, which is similar to the MPLS
data format. If tunnel is OTN, the tunnel format is IP/Ethernet over
ODU.
2.2. The Benefit of Overlay Network Structure
(1) Lower cost down for Core Routers: For the Core Router, it is not
required to compute route, and distribute protocol signal. The
Core Routers only store the equipment IP prefix, and do not
store user IP prefix any more. The RIB and FIB table for core
Router are very small. The size routing tables in the Core
Routers does not increase and remains stable with the growth of
the numbers of users.
(2) Improved network security: The overlay network structure
improves network security by splitting(and hence isolating)the
provider equipment and user station. The attacks from hacker to
core routers would therefore be separated by the edge routers.
(3) Support of network virtualization: Some of the control and
computing function could be separated from Edge Router and be
done by controller. The edge router in the future is a hardware
platform. The service, policy ,and other control function, such
as route computing, signal distribution can be furnished by
special physical/virtual servers. The network virtualization
for Edge Router is discussed in section 3.
2.3. Core Router Requirements
The Core Router performs the following functions:
(1) Core Routers mainly focus on fast forwarding encapsulated data.
(2) The control plane is very simple. It announces and floods the
topology information.
(3) For compatibility reasons, Route computation may be needed, but
is not necessary.
2.4. Edge Router Requirement
The edge Router performs the following functions:
(1) Access and resources management: Edge Routers support user
Access authentication, authorization, and resource control and
management. When there is new user access network, the edge
router support user access authentication, authorization. If
Hu & Khasnabish Expires September 2, 2013 [Page 5]
Internet-Draft I2RS Overlay Mar 2013
the subscriber is legal and registered, he/she should should
pass the access authentication and authorization tests.
(2) Topology management:Edge Router gathers the network topology
information and reports the topology to the controller. When
the topology changes, the edge router reports the changes as
well.
(3) Policy management: Edge Router identifies the policy from The
I2RS Commissioner([I2RS-Policy]).
(4) Service management: Edge Router should identifies the services
and performs the appropriate encapsulation.
(5) Route and signal protocol management: Edge Router computes route
based on the topology information received from other edge
router and core router.
(6) Tunnel control and management: Edge Routers manage and maintain
tunnel information. All the edge routers are connected over
logical full-mesh based tunnel network.
(7) Traffic analysis and reporting: Edge router monitors the data
traffic, and reports the traffic updates/changes.
3. Network Virtualization(NV)
3.1. Benefits of Network Virtualization
(1) NV reduces ER complexity and equipment costs.
(2) NV allows flexibility and rapid deployment of new services;
services can also be quickly scaled up/down based on demands.
(3) Seamless support of scalability and reliability
(4) NV allows flexibility and simplicity of function combination,
for co-existence with hardware based network platform. An ER
could be utilized both as BRAS, Firewall, or NAT equipment on
the same hardware platform.
3.2. Applications and Requirements
Hu & Khasnabish Expires September 2, 2013 [Page 6]
Internet-Draft I2RS Overlay Mar 2013
(1) Tunnel gateway elements: IPSec/SSL VPN gateway.
(2) Traffic analytics: DPI, QoS measurement, SLA agent.
(3) Converged and network-wide functions: AAA Server, policy control
and charging platform.
(4) Security function: Firewalls, virus scanners, instruction
detection and prevention systems.
3.3. Network Virtualization
Edge routers can support network virtualization, An ER can be a
hardware based platform, and the other necessary functions can be
supported via separate servers A programmable interface between
functional server and edge router can be used to support this
paradigm. When there is new service, we only need to add a new
server to support that service, and there may be minimal or no
changes required to the edge router.
Hu & Khasnabish Expires September 2, 2013 [Page 7]
Internet-Draft I2RS Overlay Mar 2013
+--------------------+ +-------------------+
| +------+ +------+ | | +------+ +------+ |
| |DPI | |NAT | | | |DPI | |NAT | |
| |Server| |Server| | | |Server| |Server| |
| +------+ +------+ | | +------+ +------+ |
| +------+ | | +------+ |
| | QOS | | | | QOS | |
| |Server| | | |Server| |
| +------+ | | +------+ |
+-----+--------------+ virtualization +---------------+---+
======|=======================================================|====
. .
| +------------------------------------------------+ .
. | +--------+ +-------+ | |
|- +-->| Edge | | Edge |<--+---.
. | | Router | | Router| | |
| | +--------+ +-------+ | .
. | Overlay Network | |
| | +-------+ +-------+ | .
. | | Core |-----| Core | | |
| | | Router| | Router| | .
. | +-------+ +-------+ | |
| | | .
. | +--------+ +-------+ | |
+--+->| Edge + | Edge |<--+---+
| | Router | | Router| |
| +--------+ +-------+ |
+------------------------------------------------+
Figure 2: Network Virtualization
4. Security Considerations
TBD
5. Acknowledgements
TBD
6. IANA Considerations
TBD
Hu & Khasnabish Expires September 2, 2013 [Page 8]
Internet-Draft I2RS Overlay Mar 2013
7. Normative References
[I2RS-FRM]
Atlas, A., Nadeau, T., and D. Ward, "Interface to the
Routing System Framework",
draft-ward-i2rs-framework-01 (work in process), July 2012.
[I2RS-Policy]
Atlas, A., Hares, S., and J. Halpern, "A Policy Framework
for the Interface to the Routing System",
draft-atlas-i2rs-policy-framework-00 (work in process),
September 2012.
Authors' Addresses
Fangwei Hu
ZTE
No.889 Bibo Rd
Shanghai, 201203
China
Phone: +86 21 68896273
Email: hu.fangwei@zte.com.cn
Bhumip Khasnabish
ZTE USA Inc.
55 Madison Avenue, Suite 160
Morristown, New Jersey 07960
USA
Phone: +001-781-752-8003
Email: Bhumip.khasnabish@zteusa.com
Hu & Khasnabish Expires September 2, 2013 [Page 9]