Improved Path Exploration in shim6-based Multihoming S ebastien - - PowerPoint PPT Presentation
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Improved Path Exploration in shim6-based Multihoming S ebastien Barr e , Olivier Bonaventure Universit e catholique de Louvain http://inl.info.ucl.ac.be
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions
S´ ebastien Barr´ e, Olivier Bonaventure
Universit´ e catholique de Louvain http://inl.info.ucl.ac.be
SIGCOMM 2007 Workshop “IPv6 and the Future of the Internet”
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions
1
Introduction to Shim6 and REAP Introduction to Shim6 Shim6 : a new layer The REAP exploration protocol
2
Analysis of exploration time Shim6 implementation and lab EX1 : Measuring exploration times EX2 : Finding better paths
3
Conclusions
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Introduction to Shim6 Shim6 : a new layer The REAP exploration protocol
1
Introduction to Shim6 and REAP Introduction to Shim6 Shim6 : a new layer The REAP exploration protocol
2
Analysis of exploration time Shim6 implementation and lab EX1 : Measuring exploration times EX2 : Finding better paths
3
Conclusions
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Introduction to Shim6 Shim6 : a new layer The REAP exploration protocol
Internet
’A’ ’B’, ISPX.B Source Destination ISP1.A ISP2.A
ISP1 ISP2
ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Introduction to Shim6 Shim6 : a new layer The REAP exploration protocol
Internet
’A’ ’B’, ISPX.B Source Destination src : ISP1.A dest : ISPX.B ISP1.A ISP2.A
ISP1 ISP2
DATA
ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Introduction to Shim6 Shim6 : a new layer The REAP exploration protocol
Internet
’A’ src : ISP2.A dest : ISPX.B ’B’, ISPX.B Source Destination ISP1.A ISP2.A
ISP1 ISP2
DATA
ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Introduction to Shim6 Shim6 : a new layer The REAP exploration protocol
Application Transport Network Physical Datalink
IP address = identifier (ULID) IP address = locator
ULPs IP : Endpoint functions SHIM IP : Routing functions
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Introduction to Shim6 Shim6 : a new layer The REAP exploration protocol
Application Transport Network Physical Datalink IP : Endpoint functions IP : Routing functions
IP address = locator IP address = identifier (ULID)
ULPs SHIM
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Introduction to Shim6 Shim6 : a new layer The REAP exploration protocol
Application Transport Network Physical Datalink IP : Endpoint functions IP : Routing functions ULPs SHIM
IP address = identifier IP address = locator (ULID)
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Introduction to Shim6 Shim6 : a new layer The REAP exploration protocol
ULID : Used as the identifier throughout a transport connection. locator : IPv6 address used for routing (locating the peer). Shim6 performs a mapping between ULIDs and locators, by use of context tags.
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Introduction to Shim6 Shim6 : a new layer The REAP exploration protocol
Internet
’A’ ’B’, ISPX.B Source ISP1.A ISP2.A
ISP1 ISP2
DATA
Destination
ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Introduction to Shim6 Shim6 : a new layer The REAP exploration protocol
negotiation Shim6
Internet
’A’ ’B’, ISPX.B Source ISP1.A ISP2.A
ISP1 ISP2
DATA
Destination
ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Introduction to Shim6 Shim6 : a new layer The REAP exploration protocol
Internet
’A’ ’B’, ISPX.B Source ISP1.A ISP2.A
ISP1 ISP2
DATA
Destination
context tag: B_flow1 locators :
ISP1.A ISPX.B* ISP1.A* ISP2.A , ISP1.A* ISP2.A , Shim6 context locators :
ISPX.B* ISPX.B ISP1.A context tag: A_flow1
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Introduction to Shim6 Shim6 : a new layer The REAP exploration protocol
Internet
’A’ ’B’, ISPX.B ISP1.A ISP2.A
ISP1 ISP2
DATA DATA
Shim6 context locators :
ISPX.B* ISPX.B ISP1.A context tag: A_flow1
REAP
Shim6 context context tag: B_flow1 locators :
ISP1.A ISPX.B* ISP1.A* ISP2.A ,
OK
ISP1.A* ISP2.A ,
OK
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Introduction to Shim6 Shim6 : a new layer The REAP exploration protocol
REAP probe
Internet
’A’ ’B’, ISPX.B ISP1.A ISP2.A
ISP1 ISP2
REAP probe DATA DATA
Shim6 context locators :
ISPX.B* ISPX.B ISP1.A context tag: A_flow1
REAP
Shim6 context context tag: B_flow1 locators :
ISP1.A ISPX.B*
Expl.
ISP1.A* ISP2.A ,
OK
ISP1.A* ISP2.A ,
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Introduction to Shim6 Shim6 : a new layer The REAP exploration protocol
DATA
’A’ ’B’, ISPX.B ISP1.A ISP2.A
ISP1 ISP2
REAP probe DATA
Internet
Shim6 context locators :
ISPX.B* ISPX.B ISP1.A context tag: A_flow1
REAP
Shim6 context context tag: B_flow1 locators :
ISP1.A ISPX.B*
OK Expl.
ISP1.A* ISP2.A , ISP1.A ,ISP2.A*
Inbd
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Introduction to Shim6 Shim6 : a new layer The REAP exploration protocol
REAP probe DATA
Internet
’A’ ’B’, ISPX.B ISP1.A ISP2.A
ISP1 ISP2
DATA
OK
Shim6 context locators :
ISPX.B* ISPX.B ISP1.A context tag: A_flow1 ISP1.A ,ISP2.A*
REAP
Shim6 context context tag: B_flow1 locators :
ISP1.A ISPX.B* ISP1.A , ISP2.A*
OK Inbd
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Introduction to Shim6 Shim6 : a new layer The REAP exploration protocol
Internet
’A’ ’B’, ISPX.B ISP1.A ISP2.A
ISP1 ISP2
DATA
OK
Shim6 context locators :
ISPX.B* ISPX.B ISP1.A context tag: A_flow1 ISP1.A ,ISP2.A*
REAP OK
Shim6 context context tag: B_flow1 locators :
ISP1.A ISPX.B* ISP1.A , ISP2.A*
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Introduction to Shim6 Shim6 : a new layer The REAP exploration protocol
recovery failure REAP
10 20 30 40 50 60 10 20 30 40 50 60
Throughput (Mbits/sec) time (seconds) Path 2 used Path 1 used Figure: Evolution of throughput for an iperf TCP session
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Shim6 implementation and lab EX1 : Measuring exploration times EX2 : Finding better paths
1
Introduction to Shim6 and REAP Introduction to Shim6 Shim6 : a new layer The REAP exploration protocol
2
Analysis of exploration time Shim6 implementation and lab EX1 : Measuring exploration times EX2 : Finding better paths
3
Conclusions
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Shim6 implementation and lab EX1 : Measuring exploration times EX2 : Finding better paths
The detection time is defined as the interval between the
The exploration time is the interval between leaving and coming back to the operational state.
Probes are sent to various paths by randomly selecting an address pair, thus a path. 4 probes are sent with a 500ms interval, then exponential backoff is performed.
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Shim6 implementation and lab EX1 : Measuring exploration times EX2 : Finding better paths
LinShim6 v0.4.3, with Linux kernel 2.6.17.11
Available at http://inl.info.ucl.ac.be/LinShim6
Click modular router, to meet the following needs :
Simulate broken paths : we are able to stop or restart any path
Simulate path delays : We can configure a specific artificial delay for each address pair. Perform source-address based routing : The testbed is configured with one queue for each address pair.
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Shim6 implementation and lab EX1 : Measuring exploration times EX2 : Finding better paths
80ms
0ms 80ms 0ms
2002:1::if_id_B 2002:2::if_id_B 2002:3::if_id_B
Click modular router
2001:1::if_id_A 2001:2::if_id_A 2001:3::if_id_A
Host A Host B
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Shim6 implementation and lab EX1 : Measuring exploration times EX2 : Finding better paths
n : number of broken queues The current queues for both directions are always broken (bidirectional failure) example for n = 3 :
2002:1::if_id_B 2002:2::if_id_B 2002:3::if_id_B
2001:1::if_id_A 2001:2::if_id_A 2001:3::if_id_A
Host A Host B
Click modular router
ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Shim6 implementation and lab EX1 : Measuring exploration times EX2 : Finding better paths
10 20 30 40 50 60 70 80 90 100 0.5 1 1.5 2 CDF (%) exploration time (seconds) n=1
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Shim6 implementation and lab EX1 : Measuring exploration times EX2 : Finding better paths
10 20 30 40 50 60 70 80 90 100 0.5 1 1.5 2 CDF (%) exploration time (seconds) n=1 n=2
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Shim6 implementation and lab EX1 : Measuring exploration times EX2 : Finding better paths
10 20 30 40 50 60 70 80 90 100 0.5 1 1.5 2 CDF (%) exploration time (seconds) n=1 n=2 n=3
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Shim6 implementation and lab EX1 : Measuring exploration times EX2 : Finding better paths
10 20 30 40 50 60 70 80 90 100 0.5 1 1.5 2 CDF (%) exploration time (seconds) n=1 n=2 n=3 n=4
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Shim6 implementation and lab EX1 : Measuring exploration times EX2 : Finding better paths
10 20 30 40 50 60 70 80 90 100 0.5 1 1.5 2 CDF (%) exploration time (seconds) n=1 n=2 n=3 n=4 n=5
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Shim6 implementation and lab EX1 : Measuring exploration times EX2 : Finding better paths
10 20 30 40 50 60 70 80 90 100 0.5 1 1.5 2 CDF (%) exploration time (seconds) n=1 n=2 n=3 n=4 n=5 n=6
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Shim6 implementation and lab EX1 : Measuring exploration times EX2 : Finding better paths
We have selected a path, is it the best one ? Let’s compare in terms of delay.
80ms
0ms 80ms 0ms
2002:1::if_id_B 2002:2::if_id_B 2002:3::if_id_B
Click modular router
2001:1::if_id_A 2001:2::if_id_A 2001:3::if_id_A
Host A Host B
ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Shim6 implementation and lab EX1 : Measuring exploration times EX2 : Finding better paths
We break one path for each direction. What are the alternative paths chosen by the protocol ?
2002:1::if_id_B 2002:2::if_id_B 2002:3::if_id_B
0ms 0ms 80ms
Click modular router
2001:1::if_id_A 2001:2::if_id_A 2001:3::if_id_A
Host A Host B
80ms
ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Shim6 implementation and lab EX1 : Measuring exploration times EX2 : Finding better paths
10 20 30 10 20 30 40 50 60 70 80 % One-way delay (ms) Default REAP
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions Shim6 implementation and lab EX1 : Measuring exploration times EX2 : Finding better paths
10 20 30 10 20 30 40 50 60 70 80 % One-way delay (ms) Default REAP 4 probes sent in burst
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions
1
Introduction to Shim6 and REAP Introduction to Shim6 Shim6 : a new layer The REAP exploration protocol
2
Analysis of exploration time Shim6 implementation and lab EX1 : Measuring exploration times EX2 : Finding better paths
3
Conclusions
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions
Our implementation for the Linux kernel shows that multihoming with Shim6 is possible. REAP provides an additional capability, that is, failure detection and recovery by timeouts and probe sending. In most cases the path exploration may be done reasonably fast. We argue that REAP could also be used for finding paths with better/best delays, although we should care not to overload the network with signalling load.
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions
Evaluation and optimization of the detection time Use heuristics to find better paths according to some criteria (delay, bandwidth,. . . ) Find an ordering of address pairs for path exploration that would perform better than the current random selection.
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming
Outline Introduction to Shim6 and REAP Analysis of exploration time Conclusions
S´ ebastien Barr´ e, Olivier Bonaventure Improved Path Exploration in shim6-based Multihoming