Transcript 20060718-bpc-bmm

Backbone Performance
Comparison
Jeff Boote, Internet2
Warren Matthews, Georgia Tech
John Moore, MCNC
1
Overview
• We (in NC) were asked to compare the relative
performance of various IP service providers
 Interest from both local CIOs and Internet2
• We decided to measure relative end-to-end
latency and jitter
• Recruited a few other ITECs (Ohio and Texas)
and GA Tech to help
• Jeff Boote got interested since we were using
owamp
2
Method
• Setup owamp machine at each site with multiple
interfaces per NIC
• Use host routes to force traffic to a specific
destination via a specific provider
• Create a mesh of these running continuously
and dump results to a database
• Add traceroute information to verify paths and
look for routing changes
3
Path types
• Path will vary
depending on
whether source
and destination
sites share
provider, or not.
• Doesn’t take
“natural” or policy
routing into
consideration,
but useful for
comparative
purposes.
4
As we progressed…
• New paths became available…
 VPLS (Layer 2 VLAN) between three of the ITECs (NC, OH and
TX)
 Described in sidebar
 NLR PacketNet between NC and GT
 Not all that interesting, since both sites attach to the same NLR
router in Atlanta
• Added NLR to new interface on same NIC, added VPLS
to a separate NIC on the same machines
• TAMU site setup and running, but o good data available
yet
 Had to remove host routes due to other routing changes going
on locally
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Available Data from OWAMP
•
•
•
•
•
•
Latency
Latency variation (jitter ~ 95%-min)
TTL (num hops)
Duplicates
Loss
Reordering (not likely at 1 pps)
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OWAMP “sender”
configuration
Only last router before “backbone” shown
• Each host has multiple
virtual addresses
configured (one per
“network”)
• Continuous stream of
packets (1 pps - exp dist.)
per network address
“pair”
• Traffic is directed onto
specific network based
on dest address
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LATAB
(Traceroute when source is routed through Abilene)
OH
nms4-ipls
IPLS
CHIN
NYCM
KSCY
NC
WASH
nms4-hstn
HSTN
ATLA
TAMU
GT
nms4-wash
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LATQW
(Traceroute when source is routed through Qwest)
CHI-EDGE
CHI-CORE
DCA-CORE
DCA-EDGE
NC
ATLA-CORE
ATLA-EDGE
OH
GT
9
LATL3
(Traceroute when source is routed through Level3)
Qwest
Washington
Washington
Washington
Asymmetric routing:
Northbound via Charlotte
Southbound via Raleigh.
Raleigh
Unknown
NC
Charlotte
Charlotte
Atlanta
OH
Unknown
Unknown
GT
ATLAL3
10
LATO3
(Traceroute when source is routed through another provider - GT/Cogent)
OH
Qwest
NC
CORE
ATLA
GT
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LATNLR
ATLA
NC
GT
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LATVPLS
OH
NC
TAMU
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Preliminary Results
• Small amount of data collected so far
• Working on how best to visualize
combination of pieces (latency, loss,
routing changes, etc.)
 Looking for “stability” metric (but stability is
application dependent)
• More analysis needed
14
Loss overview
15
NC to GT
•
NLR is lower latency.
 This is expected as GT and
NC are connected to the
same router.
 NC connection is backhauled
via NLR L2 service.
Qwest
NLR
•
Qwest and Abilene go via
Washington.
 The long way…
•
Level3
Abilene
For the Level3 path, there is
an unidentified hop just before
the GT campus.
 Rate limiter?
 Expected NLR and Level3
paths to be closer
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GT to NC
NLR
Qwest
Cogent
Level3
Abilene
• NLR and Level3
paths similar
• Cogent hands off to
Qwest to get to NC
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Latency Range
NC to GT
14
Range of Latency Between NC and GT
12
10
Latency (ms)
Level3 via
Raleigh
8
6
4
Level3 via
Charlotte
2
Input to GT is always longer?
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0
AB_GT_NC
AB_NC_GT
L3_GT_NC
L3_NC_GT
QW_GT_NC
QW_NC_GT
NLR_GT_NC
NLR_NC_GT
NC to OH
Qwest
Level3
• Marginally quicker
across Qwest (via
Washington and
Chicago).
• Abilene via New York,
Chicago and
Indianapolis.
Abilene
19
OH to NC
•
Qwest
Abilene
OH doesn’t use Level3,
so no return path to NC
via Level3
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Latency Range
NC to OH
22
Latency Range Between NC and OH
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Latency (ms)
20
No return path for L3_NC_OH
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AB_OH_NC
AB_NC_OH
L3_OH_NC
QW_OH_NC
QW_NC_OH
GT to OH
Abilene
Cogent
• Abilene more direct
via Indianapolis
• Qwest via Chicago
• Cogent, Level3 hand
off to Qwest
Qwest
Level3
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OH to GT
•
Qwest
OH doesn’t use Level3,
so no return path to GT
via Level3
Abilene
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Latency Range
GT to OH
30
Latency Range Between GT and OH
25
No return path for L3_GT_OH.
Latency (ms)
20
15
10
5
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0
AB_GT_OH
AB_OH_GT
L3_OH_GT
QW_GT_OH
QW_OH_GT
Summary
• From a latency perspective, topology is the
overriding parameter
 So far we’re not seeing huge latency deltas between
R&E and commodity between two endpoints
• Loss in commodity networks is pretty good
 They’ve improved in the last 10 years
• Looking for a quality metric (stability?) to
combine the things we can measure
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VPLS Sidebar
• Virtual Private LAN Service - multipoint
Ethernet service over IP/MPLS backbone
• Created between ITECs as overlay on
Abilene
• PE routers sit in GigaPoP address space,
interconnected via interdomain LSPs
• Abilene T640s are P routers
26
VPLS Overview
•
•
•
Full Mesh of LSPs
BGP for inter-PE communication
Ethernet encapsulation at PE-CE
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View from Ohio
To NC
To TX
No routers!
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View from NC PE
Local NC MAC
address
TX MAC
address
OH MAC
address
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