Internet DRAFT - draft-chen-tsvwg-crosslayer-cooperation
draft-chen-tsvwg-crosslayer-cooperation
Network Working Group H. Chen
INTERNET-DRAFT Y. Yin
Intended Status: Informational Huawei Technologies
Expires: September 21, 2016 G.Chen
China Telecom
March 20, 2016
Cross-layer Cooperation for Encrypted Traffic
draft-chen-tsvwg-crosslayer-cooperation-00
Abstract
This memo mainly considers the requirement and feasibility of cross-
layer design in the encrypted traffic scenario.
By permitting the interaction between the encrypted application layer
and non-encrypted transport/network layer, the network layer may
schedule service flow more properly and the application layer may
know the network status information well, which actually optimize the
network bandwidth.
Status of this Memo
This Internet-Draft is submitted to IETF in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as
Internet-Drafts.
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."
The list of current Internet-Drafts can be accessed at
http://www.ietf.org/1id-abstracts.html
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html
This Internet-Draft will expire on September 21, 2016.
Copyright and License Notice
Chen & Yin, et al Expires September 21, 2016 [Page 1]
Internet-Draft Cross-layer Cooperation March 2016
Copyright (c) 2016 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
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 . . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Cross-layer Cooperation for Encrypted Traffic . . . . . . . . . 3
2.1 Up to down information sharing . . . . . . . . . . . . . . . 4
2.2 Down to up information sharing . . . . . . . . . . . . . . . 4
3 Extended Discussion . . . . . . . . . . . . . . . . . . . . . . 5
3.1 Mobile Video Scenario . . . . . . . . . . . . . . . . . . . 5
3.2 Future Discussion . . . . . . . . . . . . . . . . . . . . . 6
4. Security Considerations . . . . . . . . . . . . . . . . . . . . 6
5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 6
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 6
7. References . . . . . . . . . . . . . . . . . . . . . . . . . . 6
7.1 Normative References . . . . . . . . . . . . . . . . . . . 6
7.2 Informative References . . . . . . . . . . . . . . . . . . 7
1. Introduction
Implemented by OTT, the encrypted traffic is increasing on the
Internet over the past few years and will continue to increase. This
brings up the problem for the network operator to effectively manage
the flows. The reason lies in that network devices(e.g router,
firewall, DPI) controlled by Operator could not parse the flow
contents sending by server/client controlled by OTT. Traffic
encryption in fact hinders most existing bandwidth optimization
methods.
Seeing from the layering perspective, as shown in Figure.1, traffic
encryption results in the application layer disconnection between OTT
Chen & Yin, et al Expires September 21, 2016 [Page 2]
Internet-Draft Cross-layer Cooperation March 2016
controlled devices and Operator controlled devices.
Cross-layer cooperation is one possible way to resolve the problem.
It removes the strict boundaries between each layer to allow
communication between them. For example, by permitting transport
layer to access the data of application layer to exchange information
and enable interaction, network devices is able to learn OTT
information contents to implement bandwidth optimization.
OTT
+-------------- Controlled -------------+
| |
| |
| Operator |
| Controlled |
| | |
.........|....... ........|........ .......|.........
. . . . . .
. +-----------+ . . +-----------+ . . +-----------+ .
. |Application|<---X--->|Application|<---X--->|Application| .
. +-----------+ . . +-----------+ . . +-----------+ .
. . . . . .
. +-----------+ . . +-----------+ . . +-----------+ .
. | Transport |<------->| Transport |<-------> Transport | .
. +-----------+ . . +-----------+ . . +-----------+ .
. . . . . .
. +-----------+ . . +-----------+ . . +-----------+ .
. | Network |<------->| Network |<------->| Network | .
. +-----------+ . . +-----------+ . . +-----------+ .
................. ................. .................
Client L4-L7 Server
Network Device
Figure.1 Problem with traffic encryption
2. Cross-layer Cooperation for Encrypted Traffic
The problem with the encrypted traffic is the inaccessible of some
useful information which required by operator to manage their
networks. For example, without flow types and flow control
information, network operator can not predict the traffic evolution
in real time[Dadas].
Information sharing between the encrypted part and non-encrypted part
is vital to make the bandwidth optimization possible. As shown in
Figure.2, it can be generalized to bidirectional interactive: (a)up
Chen & Yin, et al Expires September 21, 2016 [Page 3]
Internet-Draft Cross-layer Cooperation March 2016
to down information sharing and (b)down to up information sharing.
.........................
. +-------------------+ .
. | Application Layer | . Encrypted
. +-+---------------^-+ .
....|...............|....
| |
(a)| |(b)
| |
| |
| |
....v...............+....
. +-------------------+ .
. | Transport Layer | .
. +-------------------+ . Non-encrypted
. .
. +-----------------+-+ .
. | Network Layer | .
. +-------------------+ .
.........................
Figure.2 Cross-layer cooperation for traffic encryption
2.1 Up to down information sharing
Through the interfaces the application layer opened up, it may send
data down to network layer for network management benefits. The data
can be one bit to indicate the encryption state or several bits to
indicate the flow types and flow control information. The network
device needs these information to determine in which way to deal with
the flow.
2.2 Down to up information sharing
Through the interfaces the network layer opened up, it may send data
up to the application layer for network management/optimization
benefits. These data include some more detailed flow information
required by the network devices. Then the application layer may share
the required information with the transport layer or network layer to
enable the fine-grained flow management.
For example, the network device may inform the server/client to share
URL information included in flow content, in case that the flow be
blocked by middle box as malicious traffic due to encryption.
Chen & Yin, et al Expires September 21, 2016 [Page 4]
Internet-Draft Cross-layer Cooperation March 2016
3 Extended Discussion
Cross-layer cooperation is useful in some other scenario in addition
to traffic encryption scenario. Mobile video service is a good
example with the emerging AR/VR technique. A more powerful network is
demand to provide sufficient bandwidth and the wide dynamic range.
3.1 Mobile Video Scenario
Existing TCP-based video streaming transmission is hard to meet the
requirement, especially when experiencing a long RTT scenario or in
the wireless scenario with high packet loss ratio. All these will
result in an inefficient use of network bandwidth and thus seriously
impact the user's experience.
Cross-layer cooperation may help to solve this problem and Figure.3
shows some example of interactive among protocol layers:
+-------------------+
| Application Layer +---+
+-------------------+ |
|
|
+-------------------+ |
| Transport Layer | |
+-^---------------+-+ |
| | |
| | |
(a)| (b)| |(c)
| | |
| | |
| | |
+-+---------------v-+ |
| Network Layer <---+
+-------------------+
Figure.3 Cross-layer cooperation for mobile video service
Arrow(a) indicates that the network layer may share information with
transport layer. Examples include ECN[ECN] and CQIC[CQIC]. By
permitting transport layer to obtain the network layer information
such as congestion state or bottleneck bandwidth information,
bandwidth optimization can be achieved.
Arrow(b) indicates that the transport layer may share some
Chen & Yin, et al Expires September 21, 2016 [Page 5]
Internet-Draft Cross-layer Cooperation March 2016
information with the network layer. Example could be accurate
congestion notification. The transport layer will inform the network
layer the type of information of interest. Then the network layer may
provide these information to the transport layer according to certain
in-band approach and thus enable the accurate congestion
notification.
Arrow(c) indicates that the application layer may share information
with network layer. Typical example include Path Element
Computing(PCE). For PCE, the application layer will compute the
desired routing path and share this information with the network
layer to enable the routing path optimization.
3.2 Future Discussion
In the original OSI networking model, strict boundaries between
layers are enforced, where data are kept strictly within a given
layer. Cross-layer cooperation removes such strict boundaries to
allow communication between layers. It permits one layer to access
the data of another layer in certain way to exchange information and
enable interaction.
With the fast-growing demand of high-bandwidth value-added services,
network model itself need to evolve. Interactive network model which
employs cross-layer cooperation should be take into consideration.
4. Security Considerations
Security considerations are not addressed in this document.
5. Acknowledgements
The authors would like to thank Feng Li and Jin Li for their comments
and contributions.
6. IANA Considerations
No IANA action is needed for this document.
7. References
7.1 Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March
1997, <http://www.rfc-editor.org/info/rfc2119>.
Chen & Yin, et al Expires September 21, 2016 [Page 6]
Internet-Draft Cross-layer Cooperation March 2016
7.2 Informative References
[Dadas] Dadas, M., Stephan, E., Cayla, M., Oprescu, I., "Managing
Radio Networks in an Encrypted World (MaRNEW) Workshop",
September 2015.
[ECN] Ramakrishnan, K., Floyd, S., and D. Black, "The Addition
of Explicit Congestion Notification (ECN) to IP", RFC
3168, September 2001.
[CQIC] Lu, F., Du, H., Jain, A., Voelker, G. M., Snoeren, A. C.,
Terzis, A., "CQIC: Revisiting Cross-Layer Congestion
Control for Cellular Networks ", Proceedings of The 16th
International Workshop on Mobile Computing Systems and
Applications (HotMobile), ACM (2015), pp. 45-50.
Authors' Addresses
Hao Chen
Huawei Technologies
12, E. Mozhou Rd., Jiangning Dist.,
Nanjing, Jiangsu 211111
China
Phone: +86-25-56629007
EMail: philips.chenhao@huawei.com
Yue Yin
Huawei Technologies
12, E. Mozhou Rd., Jiangning Dist.,
Nanjing, Jiangsu 211111
China
Phone: +86-25-56629013
EMail: yinyue@huawei.com
Ge Chen
China Telecom
109, E. Zhongshan Ave., Tianhe Dist.,
Guangzhou, Guangdong 510630
China
Phone: +86-020-38639392
EMail: cheng@gsta.com
Chen & Yin, et al Expires September 21, 2016 [Page 7]
