Internet DRAFT - draft-palanivelanchetansenthil-mptcp-enhancements
draft-palanivelanchetansenthil-mptcp-enhancements
INTERNET-DRAFT A. Palanivelan
Intended Status: Experimental Verizon Labs
Expires: Apr 19, 2016 Chetan Harsha
Verizon Labs
Senthil Sivakumar
Cisco Systems
Oct 17, 2015
MPTCP Enhancement Opportunities
draft-palanivelanchetansenthil-mptcp-enhancements-00
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INTERNET DRAFT MPTCP Enhancement Opportunities Oct 17,2015
Abstract
MPTCP Intends to address a wide range of issues, with minimal
implementation tweaks. Though this works in a range of use
cases,there are some use cases, where some standard implementation
recommendations could help. The Purpose of this draft is to document
Opportunities, where Enhancements to MPTCP can translate to more
wider deployments.
Table of Contents
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1 Terminology . . . . . . . . . . . . . . . . . . . . . . . . 3
2 MPTCP Enhancement Opportunities - End user Use cases . . . . . . 3
2.1 Short Flows vs Long Flows . . . . . . . . . . . . . . . . . 3
2.2 Application based Path selection and Adaptive buffering . . 4
2.3 Path Selection Enhancements . . . . . . . . . . . . . . . . 4
2.4 Optimal number of paths . . . . . . . . . . . . . . . . . . 5
3 UseCase Scenarios (Simulated in Lab) and Results . . . . . . . . 6
3.1 MPTCP Enabled Client Uploads data from Non-MPTCP Capable
Server . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.2 MPTCP Enabled Client Uploads data from MPTCP Enabled
Server . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.3 MPTCP Enabled Client Uploads data from Non-MPTCP Capable
Server with Intermediate MPTCP Enabled devices (proxy?) . . 6
3.4 MPTCP Enabled Client Uploads data from MPTCP Enabled
Server with Intermediate MPTCP Enabled devices (proxy?) . . 6
3.5 MPTCP Enabled Client Downloads data from Non-MPTCP
Capable Server . . . . . . . . . . . . . . . . . . . . . . 7
3.6 MPTCP Enabled Client Downloads data from MPTCP Enabled
Server . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.7 MPTCP Enabled Client Downloads data from Non-MPTCP
Capable Server with Intermediate MPTCP Enabled devices (proxy?) . 7
3.8 MPTCP Enabled Client Downloads data from MPTCP Enabled
Server with Intermediate MPTCP Enabled devices (proxy?) . . 7
4 Security Considerations . . . . . . . . . . . . . . . . . . . . 8
5 IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 8
6 References . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
6.1 Normative References . . . . . . . . . . . . . . . . . . . 8
6.2 Informative References . . . . . . . . . . . . . . . . . . 8
Author's Addresses . . . . . . . . . . . . . . . . . . . . . . . . 8
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INTERNET DRAFT MPTCP Enhancement Opportunities Oct 17,2015
1 Introduction
The Scope of the use cases discussed is limited to impact on end-user
experience only and recommended updates at SP (PE Router). The
initial versions of this draft would document findings from tests
covering various end-user use cases in detail, that presents mptcp
enhancement opportunities. The later versions of the document would
strive to provide solutions for the documented usecase scenarios.
1.1 Terminology
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 RFC 2119 [RFC2119].
2 MPTCP Enhancement Opportunities - End user Use cases
2.1 Short Flows vs Long Flows
Internet traffic MUST have Security, Throughput, Reliability,.. taken
care across different network conditions, modes of access and flows.
Data access can be categorized into short or long flows.
Too many Small Flows => Higher Number of Transactions. But, much less
Bandwidth Consumption
Can we achieve Low latency for short flows?
Average completion of flow with mptcp can be higher than
completion time without mptcp With Bunch of Short Flows, MPTCP may
negatively impact throughput
Even a single lost packet can force an entire connection to wait
for an RTO.
Far Lesser Long Flows => Lesser Number of Transactions. But, higher
Bandwidth Consumption
Can we achieve higher Throughput for Long Flows Without
compromising on performance?
How do we maintain Reliability? How do we manage tolerance to
sudden and high bursts of traffic?
In Summary, Both long and short flows are important from the enduser
perspective. We need to come up with appropriate definition and clear
demarcation for short and long flows, from MPTCP Perspective. These
need be dealt differently (Probably with multiple profiles).
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2.2 Application based Path selection and Adaptive buffering
How much of benefit it would be when we consider different type of
applications, for better mptcp profiling. Typical internet
applications are categorized as Elastic and InElastic.
Elastic vs Inelastic Applications..How does it matter to MPTCP?
MPTCP performance is impacted :
When the size of the receive buffer is limited.
Path with high RTT may result in the receive buffer size
growing beyond the allowed maximum
Diversified RTT
Different ways of handling packets => Better Performance.
In Summary, Application based Path Selection and Adaptive Buffering
can help with the above scenarios. Tweaking the buffer sizes based on
the type of application and/or network condition can positively
impact the flows.
2.3 Path Selection Enhancements
Path Selection is one of the important part of MPTCP. Though there
are existing tools that help diagnose issues in the path, there still
is scope to fine tune it further flexible based on certain factors.
Usecases where MPTCP path selection can be enhanced:
For High packet loss and High latency networks?
Multiple profiles to dynamically switch (move across) the
networks?
Roaming scenarios
In Summary, The best optimal path is ever changing in the Internet.
Frequent switching may cause unnecessary overheads and can impact
performance. Enhanced yet controlled Path Selection and Path
Switching can help get better performance out of the network.
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INTERNET DRAFT MPTCP Enhancement Opportunities Oct 17,2015
2.4 Optimal number of paths
The best and effective path selection is critical to the effect of
MPTCP for the client application. How about the optimal number of
sub-flows? Can we improve client experience by controlling number of
sub flows based on certain factors?
Controlling the number of sub flows getting created:
How many is too many?
Can this be controlled? What Inputs to Consider?
Based on Network Characteristics
Historic data (region wise)
In Summary, MPTCP being not too strict as well as not too flexible,
Certain profiling based on detailed analysis of data can positively
impact MPTCP experience
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INTERNET DRAFT MPTCP Enhancement Opportunities Oct 17,2015
3 UseCase Scenarios (Simulated in Lab) and Results
Data for enhancement opportunities are derived from our lab tests.
These tests are done in a reasonably populated, yet contained test
network. The initial set of tests are more focused on the throughput
side and covers simulated Near, Mid and Far cell network conditions.
The Intention is to get detailed data from set of tests to cover
different types of data access (short/long or elastic/inelastic
applications, mobile network conditions,..etc) as well as different
mptcp profiles (for eg. number of sub flows). The detailed analysis
and summary would be presented in the later sections of the document,
followed by design/implementation recommendations for the SPs.
3.1 MPTCP Enabled Client Uploads data from Non-MPTCP Capable Server
<Shared in IETF-94 WG Discussion.. Will be updated here>
3.2 MPTCP Enabled Client Uploads data from MPTCP Enabled Server
<Shared in IETF-94 WG Discussion.. Will be updated here>
3.3 MPTCP Enabled Client Uploads data from Non-MPTCP Capable Server with
Intermediate MPTCP Enabled devices (proxy?)
<Shared in IETF-94 WG Discussion.. Will be updated here>
3.4 MPTCP Enabled Client Uploads data from MPTCP Enabled Server with
Intermediate MPTCP Enabled devices (proxy?)
<Shared in IETF-94 WG Discussion.. Will be updated here>
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INTERNET DRAFT MPTCP Enhancement Opportunities Oct 17,2015
3.5 MPTCP Enabled Client Downloads data from Non-MPTCP Capable Server
<Shared in IETF-94 WG Discussion.. Will be updated here>
3.6 MPTCP Enabled Client Downloads data from MPTCP Enabled Server
<Shared in IETF-94 WG Discussion.. Will be updated here>
3.7 MPTCP Enabled Client Downloads data from Non-MPTCP Capable Server
with Intermediate MPTCP Enabled devices (proxy?)
<Shared in IETF-94 WG Discussion.. Will be updated here>
3.8 MPTCP Enabled Client Downloads data from MPTCP Enabled Server with
Intermediate MPTCP Enabled devices (proxy?)
<Shared in IETF-94 WG Discussion.. Will be updated here>
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INTERNET DRAFT MPTCP Enhancement Opportunities Oct 17,2015
4 Security Considerations
None
5 IANA Considerations
None
6 References
6.1 Normative References
[RFC2119] S. Bradner, "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
6.2 Informative References
[RFC6182] Ford, A., Raiciu, C., Handley, M., Barre, S., and
J.Iyengar, "Architectural Guidelines for Multipath TCP
Development", RFC 6182, March 2011.
[RFC6356] Raiciu, C., Handley, M., and D. Wischik,"Coupled Congestion
Control for Multipath Transport Protocols", RFC
6356,October 2011.
Author's Addresses
Palanivelan Appanasamy
Manager Technology, Verizon Labs
Bangalore, India
Email: palanivelan.appanasamy@verizon.com
Chetan Harsha
R&D Software Engineer, Verizon Labs
Bangalore, India
Email: chetan.harsha@verizon.com
Senthil sivakumar
Principal Engineer, Cisco systems
Durham, NC
Email: ssenthil@cisco.com
Palanivelan,Chetan,. Expires Apr 19,2016 [Page 8]
