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Application 2: Automatic private line bandwidth modification. Outline Private line view vs. IP view "Vertical" vs. "horizontal" triggers of SPC/SC setup/release CHEETAH testbed and software Prototype automatic PL bandwidth modification application. Malathi Veeraraghavan - PowerPoint PPT Presentation
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Application 2: Automatic private line bandwidth
modification
Outline Private line view vs. IP view "Vertical" vs. "horizontal" triggers of SPC/SC
setup/release CHEETAH testbed and software Prototype automatic PL bandwidth
modification application
Malathi VeeraraghavanUniversity of Virginiamvee@virginia.edu
Nov. 20, 2007
Presentation for Sycamore Networks
2
Control plane
Key differentiator for SN16000 Control plane
What type of network service is enabled by control-plane software? Dynamic circuit service (DCS)
What is missing: Applications that will trigger dynamic circuit
service
3
Type of services offered today
Private line (PL) or leased line services Business interconnect Internet access
IP service
Private line (PL) IP
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Introduction of DCS
How can DCS be introduced within the existing context of PL and IP services? PL bandwidth modification Dynamic CDN
Application 1 discussed in previous set of slides
Private line IPDynamic circuit services (DCS)
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PL bandwidth modification
Carrier approach (using Verizon example) Provide business customer web portal
access to manually request increase or decrease of PL bandwidth
Basis for this approach: PL bandwidth modification is only required
when aggregate traffic needs change
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Current ITU-T approach: "vertical"
NMS triggers SPC setup, modify, release Verizon's web portal likely
communicates with NMS
Figure I 5/G.7718/Y.1709 Hybrid intra-carrier network for SPCs (simple case)
Draft new Recommendation G.7718/Y.1709 (for consent)
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Key point
Need for increased speed of PL: Single file transfer Instead of only when aggregate traffic increases
Our recommendation: "Horizontal" approach
trigger SPC setup from end host file-transfer applications
Provide software in servers located at business to allow an enterprise user to request additional bandwidth on a PL for a single high-speed file transfer
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Horizontal approach: SPC/SC setup trigger from end-host application, e.g. storage
Private line leased between business locations: OC3c-2v (300Mbps)
Router interface cards: 1GiGE Rate limiting enforced on SN16000 GiGE ports
Business interconnect PL (300 Mbps)
Private line (PL) carriermetro ringor metro mesh network
1GigE
Enterprise
IP router
Host
Enterprise
Storageserver
1GigE
1GigE1GigE
IP router
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1
Horizontal thinking: SPC setup trigger from user application, e.g. storage
Dynamically increase PL rate to 1Gbps Decreases file transfer delay Assumes PL is the bottleneck link
Business interconnect PL (300 Mbps)
Private line (PL) carriermetro ringor metro mesh network
1GigE
Enterprise
IP router
Enterprise
Storageserver
1GigE
1GigE1GigE
IP router
Storageclient
DCSclient
Host
DCSserver
1
2
DCSserver
34
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Steps in previous slide 1: When storage client starts a backup, the DCS client
sends a message to DCS server 2: DCS server communicates via EMS or directly to
SN16000 to set up additional OC3c's, increase rate limit on GiGE port, and thus increase end-to-end bottleneck link rate to 1Gb/s
3: For scalability, deploy one DCS server per SN16000; signal egress SN16000 about increase
4: sets rate limit on GigE port 5: (not shown in figure) When files are transferred,
storage client through the signaling client can have the DCS server initiate release of additional OC3c's and decrease rate limit to 300Mbps
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UNI-C support in routers
Currently only high-end routers such as Cisco's CRS-1 and 12008XR router supports UNI-C
Business routers are not likely to be these high-end routers
Alternative solution feasible if UNI-C is to used to invoke additional OC3c circuit setup Have DCS server deployed per IP router
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G.7718 states
"The CP-MP interface shall support ... The ability to invoke the setup of a SPC The ability to invoke the release of a SPC The ability to invoke the modify operation of a SPC ... Notifications of the setup, release and modifications
of SCs" Private line type view Notifying MP of SPC/SCs will be too expensive
if SPC/SCs are short-held
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PL view vs. IP view
The ITU-T approach: "PL view" Views the provisioning of SPCs and SCs as
comparable to "private line" Durations: Long-held
"IP view" While an IP router keeps count of the number
of packets in and out of its interfaces, it does not "notify" the management plane about every packet that arrives on its interfaces
Apply this view to SPC or SC setups/releases invoked by "horizontal" host applications
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Two "new" concepts
Increase speed for single file transfers Rather than only when aggregate demand
increases Invoke SPC/SC setup/release from end
host applications rather than from NMS
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File transfer delay
File transfer delay is determined by bottleneck link rate, r = min(r1, r2, r3, r4, r5)
packet loss rate on end-to-end path, Ploss
round-trip time (RTT) On lightly loaded paths, RTT and Ploss do not
matter for large files Only bottleneck link rate, r, matters
r1 r5
r4
r3r2
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Throughput - approximate formula
Throughput is effective rate, reffective
Parameters r: Bottleneck link rate RTT: Round-Trip Time MSS: Maximum Segment Size p: Packet loss on the path
The macroscopic behavior of the TCP congestion avoidance algorithm by Mathis, Semke, Mahdavi & Ott in Computer Communication Review, 27(3), July 1997
)1
,min(pRTT
MSSrreffective
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TCP/IP file-transfer delays
In heavily loaded paths, e.g., if Ploss = 1% RTT = 50ms
effective transfer rate 1.8Mbps if r is more than this value, it does not determine
effective rate. Ploss and RTT are main factors. if increasing r causes Ploss to decrease, effective
rate can be improved. Metro area, e.g.
RTT = 1ms, Ploss = 1% effective transfer rate 75Mbps
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File-transfer delay (approximation)
For large files: File-transfer delay: D (sec) File size: S (bits) Throughput: reffective (b/s)
effectiverS
D
1919
Outline check
Outline Private line view vs. IP view "Vertical" vs. "horizontal" triggers of
SPC/SC setup/release CHEETAH testbed and software Prototype automatic PL bandwidth
modification application
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CHEETAH concept
NIC 1
NIC 2
RSVP-TE client Application
TCP/IP
C-TCP/IP
End Host
NIC 1
NIC 2
RSVP-TE clientApplication
TCP/IP
C-TCP/IP
End Host Internet
SONET circuit-
switched network
SN16000 SN16000
Circuit-TCP: TCP minus congestion control; use if circuit is host-to-host.
Use high-speed circuit for file transfer applicationsCircuits: GigE VLAN mapped to OC3cNv circuit mapped to GigE VLANNIC1 and NIC2: GigE network interface cardsSN16000 links to Internet: Ethernet management portsIPsec tunnels used on Internet control-plane
CHEETAH implementation
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Signaling and routing
RSVP-TE client developed for end hosts (Linux PCs) sends RSVP-TE messages to Sycamore SN16000.
Built-in controller of SN16000 used for dynamic call setup and release
OSPF-TE used between SN16000 switches Solution works with 7.6.2.1 release of
SN16000 software: GbE mapped to OC3-7v
Extending for VLANs and sub-Gbps rates
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CHEETAH end-host software
End Host
bwlib Sig_proc
CAC
Data-planeConfiguration
RSVPD
RSVP-TE messages
Configuration file
read
circuitrequestor
Parsing/Construction
RSVP-TE client software architecture
Connection Admission Control:check if bandwidth is availableon the UNI from the host to the switch (multiple VLANs)
Configure IP routing and ARP table since remote host is reached directly on the newly setup circuit
2323
CHEETAH testbed
Atlanta
SN16000
ORNL, TN
OC192
Zelda1/2/3
3xGbE
GbE
Zelda4/5
Wukong/Wuneng
OC192
Raleigh, NC
SN16000
SN16000
•Long-distance OC192s purchased from NLR and ORNL•Collocation services purchased from MCNC in NC, SLR in Atlanta•Zeldas and wukong/wuneng: Linux Dell PCs
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Outline check
Outline Private line view vs. IP view "Vertical" vs. "horizontal" triggers of
SPC/SC setup/release CHEETAH testbed and software Prototype "automatic PL bandwidth
modification" application for storage
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New implementation required
DCS server DCS client Shell script to wrap storage (or other suitable
business file-transfer application) with DCS client Business end user "unaware" that application is
requesting bandwidth increase prior to file transfer EMS software to obtain RSVP-TE logs on
dynamic circuit setup/release for usage-based billing support
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Summary Opportunity to leverage SN16000's strength in control
plane implementation While control-plane allows carriers to offer Dynamic Circuit
Service (DCS), without applications, the service is not likely to be used by business customers
Applications identified for DCS: Dynamic CDN Automatic PL bandwidth modification
CHEETAH SN16000 based testbed available for testing applications
Looking for support: Student HR support to implement applications for dynamic
circuit services Cheetah testbed annual maintenance charges
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