1 GMPLS optical networks Malathi Veeraraghavan Professor Charles L. Brown Dept. of Electrical & Computer Engineering University of Virginia [email protected]

1

GMPLS optical networks

Malathi VeeraraghavanProfessor

Charles L. Brown Dept. of Electrical & Computer EngineeringUniversity of [email protected]

ETRI, KoreaFeb. 2009

GMPLS: Generalized MultiProtocol Label Switched networks(MPLS, SONET, WDM, SDM, VLAN)

2

Outline

• Telcom “transport network” • Cheetah vs. Dragon Approach

– Theoretical concepts

• GMPLS networks– Technologies, off-the-shelf switches, control-plane

protocols

• State of the art on different applications & networks– Commercial– Research-and-Education (REN) networks

Spectrum of services

3

Leased line IP

PDH: T1, T3switch: Digital Cross Connect (DCS)

SONET/SDH: OC3-OC768Switch: SONET/SDHcrossconnects

DWDM: OTU1-OTU3Switch: optical WDMcrossconnects

Circuit technologies: time/frequency division multiplexing

Leased lines are used to connect IP routers.Network that offers leased line service is called “transport network” by telcom industry

ATM MPLS Carrier-grade Ethernet

Packet technologies: virtual circuit switches

All the above: Data-plane technologies

Leased line

IP Router

Telco service provider(transport network) owns circuit/VC switches

Internet service provider or enterprise owns IP routers

Circuit or virtual circuit (VC) switch

IP and leased line service deployment

(1) Admins use Web interfaceto request leased line creation

Management plane(in transport network)

Network management

system

(2) NMS computes path with available bandwidth

(3) NMS sends provisioning signals to each switch on path using SNMP/CLI/TL1

Customer edge

device

Customer edge

device

Customer edge

device

Customer edge

device

Customer edge

device

switch controllerhas minimal software(SNMP agent, CLI/TL1 parser)


6

Leased line Verizon Bandwidth-on-Demand (BoD) IP

New service: rapid provisioning

Management plane + control plane

Network management

system

Customer edge

device

Customer edge

device

Customer edge

device

Customer edge

device

Customer edge

device

switch controllershave RSVP-TE software

(2) NMS still computes path with available bandwidth

(4) hop-by-hopdistributed signalingfor circuit/VCprovisioning

(3) TL1/CLI to edge node

(1) Admins use Web interfaceto request leased line creation

Progress made in telcom industry

• Data-plane progress– Excellent: interesting new switching technologies

being invented for transport networks

• Control-plane– Switch controllers implement RSVP-TE capable of

distributed route computation and admission control– But only provisioning phase is distributed

• Requests for circuits/VCs are still handled through management plane with involvement of administrators even in “Dynamic” scenarios

• Why is this an issue?– Limits access to “transport” circuit/VC network

8

Difference with R&E thinking

Scheduler

switch controllershave RSVP-TE software

(2) scheduler computes path with available bandwidth

(4) hop-by-hopdistributed signalingfor circuit/VCprovisioning

(3) TL1/CLI to edge node

externalcontroller

(1) application software running at end host initiates request for circuit/VC

(3a) configure router to filterpackets for long flow on to circuit/VC

(3a)

Enterprise

Effect of opening up access to circuit/VC “transport”

network• Application software running on end hosts deep inside enterprises can access dynamic circuit/VC services of the backbone transport network

• Circuit network reach does not need to extend all the way to the desktop

• With additional high-speed line from enterprise edge router into transport network, high-speed access can be enabled for short durations

• High call volume of setup/release: automatic generation of calls by software

• New applications!10


11

Leased line Verizon BoD eScience 10G POTS IP

Plain Old Telephone Service (64kbps)Immediate-Request (IR) mode

• unspecified call durationLow call setup overhead

( holding times can be shorter)Distributed path computation/admission controlHigh call handling volume

Book-ahead (BA) mode• call duration specified

Current solution: •centralized per-domain path computation/admission control

Low call handling volume

New services

OSCARS/DRAGON

CHEETAH

12

Outline

• Telcom “transport network” Cheetah vs. Dragon Approach

– Theoretical concepts

• GMPLS networks– Technologies, off-the-shelf switches, control-plane

protocols


13

Observations

• "Many e-science experiments ... are optimized to provide maximum throughput to a few facilities, as opposed to moderate throughput to millions of users, which is the raison d'etre for commercial networks."

• Networks should be scalable:– Metcalfe's statement: Value of a network

increases exponentially with the number of users

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Key difference between DRAGON and CHEETAH

• DRAGON focus:– For eScience

• Small number of users• High throughput to a few facilities

– Transfer technology to Internet2 • Implement and deploy software for book-ahead reservations

and circuit provisionining by teaming with ESNet and DANTE

• CHEETAH focus:– General-purpose commercial network goal to bring GMPLS

services to millions of users– But not with just moderate throughput, but also high-rate– Analyze GMPLS network bandwidth sharing modes (BA +

IR)– Implementation: IR

Background

• Types of switches• Types of bandwidth-sharing modes

– IP networks vs connection-oriented (GMPLS) networks

• Tradeoffs in GMPLS network modes– Immediate-request mode (e.g., Plain

Old Telephone Service)– Book-ahead (advance-reservation)

15

16

Types of switches

Multiplexing technique on

data-plane linksAdmissioncontrol in control plane?

Circuit switch (CS)- position based (port, time, lambda)

Packet switch (PS)- header based

Connectionless (CL) - no admission control

Not an option

e.g., Ethernet

Connection-oriented (CO)- admission control

e.g., telephoneSONET WDM, SDM

Virtual-circuit e.g., MPLS, ATM, PBBTE

GMPLS network switches

17

Difference between bandwidth (BW)-sharing modes

• In connectionless networks (e.g., IP)– Pre-1988 IP network:

• Just send data without reservations or any mechanism to adjust rates congestion collapses in the Internet in the 80s!

– Van Jacobson's 1988 contribution:• Added congestion control to TCP• Sending TCP adjusts rate

– TCP congestion-control pros and cons:• Pros: Proportional fairness and high utilization• Cons: No rate guarantees & No temporal fairness (job

seniority)

• In connection-oriented networks (e.g., GMPLS)– Key: Admission control

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Bandwidth sharing modes in GMPLS networks

• Can execute admission control in two ways:– Bufferless (immediate-request)– With buffers (book-ahead is effectively the same as having buffers to hold

calls to start in the future)

• Immediate-request: M/G/m/m model– m: number of channels on a link (servers)– if all channels are occupied, reject call

• Book-ahead: M/G/m/p model– p: max number in system: advance-reservation window K = p/m timeslots– waiting time and call blocking – K cannot be : need to block calls if per-server traffic intensity can be > 1– Or engineer the system so per-server traffic intensity ≤ 1

• Difference:– Not as the names suggest: IR calls need bandwidth immediately

• Misconception: BA with book-ahead time of “now” IR NOT TRUE

– Instead, call duration needs to be specified to support BA mode– For IR mode, applications do not need to specify duration

19

IR mode: M/G/m/mErlangB formula

mP

u

k

mP

bb

m

k

k

m

b

)1(

!/

!/

0

: offered traffic load in Erlangs: call arrival rate

1/: mean call holding time/m: per-server traffic intensitym: number of circuitsPb: call blocking probabilityub: utilization

For a 1% call blocking probability, i.e., Pb = 0.01

m ua

24.8%58.2%84.6%

110100

417117

If m is small, high utilization can only beachieved along with high call blocking probability

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• Example – To achieve a 90% utilization

with a call blocking probability less than 10%• BA-First schemes are needed

when m < 59

– To achieve a 90% utilization with a call blocking probabilityless than 20%• BA-First schemes are needed

when m < 32

Comparison of Immediate-Request (IR) and Book-Ahead (BA) schemes

U: utilizationK: number of time periods in advance-reservation window

m=10, U = 80%: PB = 23.6% m=100, U = 80%: PB = 0.4%

IR m=10, K=10, U = 80%: PB = 0.4%

BA

Link capacity C = 10Gbpsm = 10 if per-call allocation = 1Gbps

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Bandwidth sharing mechanismsin GMPLS networks

Bandwidth sharing mechanisms

Immediate-requestBook-ahead

BA-n/BA-First VBDS (Varying-Bandwidth Delayed Start)

unspecified call duration

call duration specified

session-type requests: BW, duration

data-type requests: file size(can assign any rate, even vary rate in different time

ranges)

BA-n BA-First

Users specify a set of n call-initiation time options

Users are given first available timeslot

X. Zhu, Ph.D. Thesis, UVA, http://www.ece.virginia.edu/mv/html-files/students.html

Needed if per-callcircuit rate is a largefraction of link capacity(e.g., 1Gbps circuits on a 10Gbps link, m = 10)

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Relate BW sharing modes to network types

Bandwidth-sharing mechanisms

Book-Ahead (BA)(high rate per call)

Immediate-Request (IR)(moderate rate per call)

eScience networks(small number of users)

Very large (TB, PB) file transfers need high-BW and long holding time + remote viz. need to reserve other resources such as displays.Centralized control-plane solution sufficient, since call durations are high (OSCARS+DRAGON)

What applications?Centralized control-plane(DRAGON)

general-purpose networks(large number of users)

To assign 1Gb/s on 10Gb/s per file transfer, m=10, need BA mode. Need distributed control-plane solution: small durations implies high call arrival rate at same util (load)

Moderately large (100MB, GB) file transfers assigned moderate-BW (100-300Mbps)(CHEETAH)

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References on bandwidth sharing modes

• IR mode for file transfers with moderate-BW allocation (100Mbps on 10Gbps link)– X. Fang and M. Veeraraghavan, “On using a hybrid architecture

for file transfers,” acceptedto IEEE Transactions on Parallel and Distributed Systems, 2009.

– X. Fang and M. Veeraraghavan, On using circuit-switched networks for file transfers,” in IEEE Globecom, New Orleans, LA, Nov. 2008.

– X. Zhu, X. Zheng, and M. Veeraraghavan, "Experiences in implementing an experimental wide-area GMPLS network," IEEE Journal on Selected Areas in Communications (JSAC), Apr. 2007.

– M. Veeraraghavan, X. Fang, and X. Zheng, “On the suitability of applications for GMPLS networks,” in IEEE Globecom, San Francisco, CA, Nov. 2006.

• Large-scale deployment of BA mode: (mean waiting time, blocking rate)– X. Zhu and M. Veeraraghavan, "Analysis and Design of Book-

ahead Bandwidth-Sharing Mechanisms," IEEE Transactions on Communications, Dec. 08.

– X. Zhu, M. E. McGinley, T. Li, and M. Veeraraghavan, "An Analytical Model for a Book-ahead Bandwidth Scheduler," in IEEE Globecom Washington, DC, Nov. 2007. Heterogeneous rate allocation

Is an opportunity being missed if distributed IR bandwidth sharing mode is not explored?

• Yes. Four reasons:1. Increase end-to-end rate relative to IP service; possible in the

presence of admission control (programmable patch panels to share ports)

2. Enable the creation of large-scale circuit/VC networks with moderate-rate circuits that can support a brand new class of applications

• economic value for the networking industry3. A "reservations-oriented" mode of networking to complement

today's connectionless Internet• analogy: airlines complement roadways

4. Alternative pricing models for bandwidth• Leased lines and IP service are at two extremes• Usage based pricing• Dedicated (moderately high) bandwidth for short durations instead of low

bandwidth for all time24

To increase end-to-end rate• Problem:

– WDM allows 40Gbps/channel with 80 channels/port– But, end-to-end rate is still on the order of tens of Mbps– Why? Access link rates: both for enterprises and residences

• Inter-domain link cost:– Internet2 charges $250K/year for a 1Gbps Ethernet connection– Why so high? High router port cost and no sharing

• Router port cost:– One-port 10Gbps or ten-port 1Gbps interface card costs $150-200K

• 2007 data for local access links in US:– 1.5M T1, 183K T3, 44K OC3, 21K OC12, 2K OC48 and 2.5K OC192

• Add leased lines to terminate on a space-division switch - for moderate rate, connect to sub-Gbps ports– With admission control for ports, connect high-speed link for short

duration for single flows based on request from file-transfer apps.

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What "brand new class of applications?"

• Moderate-bandwidth– Video: “Harry Potter” application,

multiple-cameras/automated cameraman for video-tel/conf, distance-learning, virtual reality

– Cloud computing, gaming– Teleoperations, telemedicine

• High-bandwidth, short-held calls– Web, P2P, storage, CDN file transfers

26

27

Outline

• Cheetah vs. Dragon Approach– Theoretical concepts

GMPLS networks– Technologies, off-the-shelf switches, control-

plane protocols


28

GMPLS related technologies• GMPLS networks

– Data-(user-) plane protocols • packet-switched: MPLS, VLAN Ethernet (PBBTE)• circuit-switched: SONET/SDH, WDM, SDM (space div. mux)

– Control-plane protocols: • RSVP-TE: signaling protocol• OSPF-TE: routing protocol• LMP: link management protocol

• Internetworking: Ethernet-over SONET/MPLS/WDM– GFP, VCAT, LCAS for SONET/SDH– PWE3 for MPLS networks– Digital wrapper for OTN

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Why internetworking?

• GMPLS networks do not exist as standalone entities as data-sourcing end hosts do not have MPLS, SONET, WDM NICs

• Instead they need to be internetworked with Ethernet interface cards:– Common usage: IP layer internetworking

• IP routers with Packet-over-SONET (PoS) interfaces– Newer usage: Ethernet layer internetworking

• Ethernet over MPLS/SONET/WDM/SDM– Port-mapped– VLAN-mapped (probably not supported with SDM)

• Ethernet interface could be on hosts or routers

Off-the-shelf GMPLS switches

30

Vendor/system Data-plane Control-plane

Cisco 12000 series MPLS switching; PWE3 Ethernet-over-MPLS

RSVP-TE, OSPF-TE

Juniper T640 MPLS switching; PWE3 Ethernet-over-MPLS

RSVP-TE, OSPF-TE

Sycamore SN16000 SONET switching;GFP/VCAT Ethernet-over-SONET (EoS)

RSVP-TE, OSPF-TEfor SONET circuits;no support for EoS

Ciena CDCI SONET switching;GFP/VCAT EoS

Proprietary signaling/routing protocols

Movaz (now Adva) RayExpress

WDM switching;G.709 Eth-over-WDM

RSVP-TE, OSPF-TE

Calient SDM switching;Ethernet-over-fiber

RSVP-TE, OSPF-TE (?)

Force10 E600 Ethernet VLAN switching None

GMPLS control-plane scope

• RSVP-TE and OSPF-TE do not have parameters to support admission control for BA calls – e.g., call duration, optional desired call-initiation time

• Strengths:– Distributed routing and call setup/release functions for

high-call volume IR calls– OSPF-TE (in each switch controller)

• Loading conditions shared only intra-area• Link-state + Distance vector (even basic OSPF)

– RSVP-TE (in each switch controller)• Route computation and admission control

– CSPF can be done only intra-area by ingress switch– Any switch could be an ingress switch – hence highly scalable

• Switch fabric configuration (i.e., provisioning) 31

Control-plane for BA calls

• Run an external scheduler to perform– path computation and admission control for future start time– add authentication and authorization

• Centralized scheduler - one per domain• Inter-domain scheduler-to-scheduler protocol:

– Abstracted topology exchange– Reservation phase (path computation + admission control)– Signaling phase (not clear why RSVP-TE is not used interdomain)

• Intradomain– Provisioning phase: RSVP-TE is used– OSPF-TE data is read out from switch controllers by scheduler for intra-

domain path computation

• Not a scalable solution to support short-duration, high-BW calls

32

33

Outline

• Cheetah vs. Dragon Approach– Theoretical concepts

• GMPLS networks– Technologies, off-the-shelf switches, control-

plane protocols

State of the art on different applications & networks– Commercial– Research-and-Education (REN) networks


34


New services

35

Commercial uses

• Semi-permanent MPLS virtual circuits– Traffic engineering– Voice over IP

• QoS concerns: telephony has a 150ms one-way delay requirement (with echo cancellers)

– Business or service provider interconnect • interconnecting geographically distributed

campuses of an enterprise• interconnecting wide-area routers of an ISP

service provider

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Traffic engineering (TE)

• Since BGP and OSPF routing protocols mainly spread reachability information, routing tables are such that some links become heavily congested while others are lightly loaded

• MPLS virtual circuits are used to alleviate this problem– e.g., NY to SF traffic could be directed to take an

MPLS virtual circuit on a lightly loaded route avoiding all paths on which more local traffic may compete

• This is an application of MPLS VCs without bandwidth allocation

37

Business or service provider interconnect (leased lines)

• Multiple options:– TDM circuits (traditional private line, T1, T3,

OC3, OC12, etc.)– Ethernet private line

• point-to-point (Ethernet over MPLS/SONET/WDM)• VPNs (called Virtual private LAN service)

– MPLS VPNs – WDM lightpaths– Dark fiber

38

Dynamic circuits/virtual circuit

(GMPLS control-plane)• Commercial:

– fast restoration • circuit/VC setup delay significant

– rapid provisioning• Verizon: Bandwidth on Demand (Just-in-Time

Provisioning)• AT&T: Shared mesh networks

– Customer Applications for dynamic network configuration

» Key industries: Financial, Media & Entertainment» Corporate Utility Backbone Networks (e.g.

reconfigure for disaster recovery)» Distribution of real-time content (e.g., Video)

• Level3: Vyvx service


39


Book-ahead (BA) mode• call duration specifie d

Current solution: •centralized per-domain path computation/admission control

Low call handling volume

New services

OSCARS/DRAGON

40

Research & Education(G)MPLS networks

• Internet2’s Dynamic Circuit network

• NSF-funded DRAGON• DOE's ESnet - Science Data

Network• DOE's Ultra Science Network (USN)

Internet2 DWDM network

http://events.internet2.edu/speakers/speakers.php?go=people&id=178

Rick Summerhill talk (10/11/2007)

InfineraDWDM system

41



Internet2 Dynamic Circuit (DC) network

Ciena CD-CIEth-SONET

switch42

Internet2 IP-routed network

JuniperT640 IP router

IP-router-to-router links on one wavelengthSONET switch-to-switch links on another wavelength

Ciena CD-CIEth-SONET

switch



43

Equipment at each PoP



44

Control-plane software(for DC network)

• OSCARS implemented in InterDomain Controller (IDC) - one per domain– Abstracted topology exchange– Interdomain scheduling– Interdomain signaling (for provisioning)

• DRAGON (intradomain control-plane)– Used in Internet2’s DC network– Intradomain routing, path computation,

signaling (for provisioning)

45

OSCARS• On-demand Secure Circuits and Advance Reservation

System (OSCARS)• DOE Office of Science and ESnet project• Co-development with Internet2• Web Service based provisioning infrastructure, which

includes scheduling, AAA architecture using X.509 certificates– Extended to include the DICE IDCP– Reservations held in SQL database

• Recall no support for book-ahead in GMPLS control protocols

• http://www.es.net/oscars/index.html

46

http://www.csm.ornl.gov/workshops/NetworkingResearchChallenges/agenda.html

Talk by Tom Lehman, Sep. 28, 2008

DRAGON• Washington DC metro-area network:

– Adva (old Movaz) WDM switches and Ethernet switches (G.709)

• Control-plane software:– Network Aware Resource Broker – NARB

• Intradomain listener, Path Computation

– Virtual Label Swapping Router – VLSR• Implements OSPF-TE, RSVP-TE• Run on control PCs external to switches (since not all switches

implement these GMPLS control-plane protocols)• Communicates with switches via SNMP, TL1, CLI to configure circuits.

– Client System Agent – CSA• End system software for signaling into network (UNI or peer mode)

– Application Specific Topology Builder – ASTB• User Interface and processing which build topologies on behalf of users• Topologies are a user specific configuration of multiple LSPs

47http://dragon.east.isi.edu

Open Source DCN Software Suite

• OSCARS (IDC)– Open source project maintained by ESNet and Internet2– Uses WDSL, XML, SQL database to store reservations– Reservations accepted with 1 minute granularity

• DRAGON (DC)– NSF-funded Open source project maintained by USC ISI

EASTand MAX

• Version 0.4 of DCNSS current deployed release– https://wiki.internet2.edu/confluence/display/DCNSS

• DCN workshops offered for training:– http://www.internet2.edu/workshops/dcn/index.html

48



DICE IDCP

• Dante, Internet2, CANARIE, ESNet• http://www.controlplane.net• IDCP: InterDomain Controller Protocol• wsdl - web service definition of message

types and formats• xsd – definition of schemas used for

network topology descriptions and path definitions

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InterDomain Controller (IDC) Protocol (IDCP)

• The following organizations have implemented/deployed systems which are compatible with this IDCP

– Internet2 Dynamic Circuit Network (DCN)– ESNet Science Data Network (SDN)– GÉANT2 AutoBahn System– Nortel (via a wrapper on top of their commercial DRAC System)– Surfnet (via use of above Nortel solution)– LHCNet (use of I2 DCN Software Suite)– Nysernet (use of I2 DCN Software Suite)– LEARN (use of I2 DCN Software Suite)– LONI (use of I2 DCN Software Suite)– Northrop Grumman (use of I2 DCN Software Suite)– University of Amsterdam (use of I2 DCN Software Suite)– DRAGON Network

• The following "higher level service applications" have adapted their existing systems to communicate via the user request side of the IDCP:

– LambdaStation (FermiLab) – CMS project on Large Hadron Collider– TeraPaths (Brookhaven) - ATLAS project on Large Hadron Collider– Phoebus

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Heterogeneous Network TechnologiesComplex End to End Paths

End System

AS 1AS 2

AS 3

VLSR

Ethernet SegmentVLSR Established VLAN

Ethernet over WDM

Ethernet over SONET

End System

Ethernet SegmentVLSR Established VLAN

VLSR

Router MPLS LSP

IP Control Plane

IP Control Plane

IP Control Plane

Ethernet

Router

Lambda Switch

SONET Switch



Example: ESNet SDNExample: Internet2 DCExample: DRAGON

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IDCP operation

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• Advance reservation request and circuit provisioning at scheduled time:• End user signals IDC with a reservation request• Authenticate requester and check authorization• Request reservation (create time, bandwidth, VLAN tag)• Signaling: creation of circuit (automatic or in response to message to IDC)

• Topology exchange: interdomain (abstracted topology information)• Monitoring

http://hpn.east.isi.edu/dice-idcp/dice-idcp-v1.0/idc-protocol-specification-may302008.doc

Route selection,admission controlcentralized per domain at IDC

Intra-domain operations

• Using DRAGON in Internet2 DCN– NARB does intra-domain path computation after

collecting routing information by listening to OSPF-TE exchanges between VLSRs

– These intradomain paths are provided to IDC for use during resource scheduling (upto 3 path options are considered)

– 5 VLSRs serve 22 CD-CIs: “subnets of CD-CIs”– In Signaling phase, VLSR sends TL1 command to

edge CD-CI, which initiates proprietary hop-by-hop signaling to configure circuit through subnet

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54

GOLE: GLIF open lightpath exchange

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DOE networks

• ESnet and Science Data Network (SDN)– OSCARS: an advance-reservation system– Science Data Network: MPLS network

• UltraScience Network– Research network for DoE labs– GbE and SONET (Ciena CD-CI)– Centralized scheduler for advance-reservation calls– 5-PoP network: ORNL, Atlanta, Chicago, Seattle,

Sunnyvale– Connections to Fermi Lab, PNNL, SLAC, CalTech

• Lambdastation: CMS project– Between Fermi Lab and Univ. of Nebraska


56


Plain Old Telephone Service (64kbps)Immediate-Request (IR) mode

• unspecified call durationLow call setup overhead

( holding times can be shorter)Distributed path computation/admission controlHigh call handling volume

New services

CHEETAH

57

NSF-funded CHEETAH network GbEthernet and SONET

TN PoP

Controlcard

GbE/10GbEcard

GA PoP

Controlcard

GbE/10GbEcard

SN16000

Controlcard

OC192card

OC-192

GbE/10GbEcard

End hosts

NC PoP

SN16000 SN16000

GaTech

End hosts

End hosts

ORNL

OC192cards

NCSUOC192card

OC-192

UVaCUNYGbE

GbEGbEs

GbE

GbE

GbEGbE

GbE

Sycamore SN16000SONET switch with GbE/10GbE interfaces

58

Networking software

• Sycamore switch comes with built-in GMPLS control-plane protocols:– RSVP-TE and OSPF-TE

• We developed CHEETAH software for Linux end hosts:– circuit-requestor

•allows users and applications to issue RSVP-TE call setup and release messages asking for dedicated circuits to remote end hosts

– CircuitTCP (CTCP) code

http://www.ece.virginia.edu/cheetah/

59

CHEETAH network usage

Application

DNS client

RSVP-TE module

TCP/IP

CTCP/IPNIC 1

NIC 2

End Host CHEETAH software

IP-routed

network

SONET circuit-switched network

CircuitGateway

CircuitGateway

Application

DNS client

RSVP-TE module

TCP/IP

CTCP/IPNIC 1

NIC 2

End HostCHEETAH software

• Bandwidth-sharing mode:• Immediate-request mode (blocked calls fall back to IP

path)• Heterogeneous rate allocation under high loads:

• higher BW for large files than for small files• Applications:

• Common file transfers (web, P2P, CDN, storage)• attempts circuits for large files (if blocked, use IP-routed

path)• use IP-routed path for small files

60

End-to-end call setup delay measurements

• Delays incurred in setting up a circuit between host zelda1 (in Atlanta, GA) and host wuneng (in Raleigh, NC) across the CHEETAH network

• Observations:– Setup delays for SONET circuits (OC1, OC3) are small (166ms) – Setup delays for Ethernet-over-SONET (EoS) hybrid circuits are much higher

(1.6s) (no standard; proprietary implementation)– Signaling message processing delays dominate end-to-end circuit setup delays

Circuit type End-to-end circuit setup

delay (s)

Processing delay for Path message at

the NC SN16000 (s)

Processing delay for Resv message at

the NC SN16000 (s)

OC-1 0.166103 0.091119 0.008689

OC-3 0.165450 0.090852 0.008650

1Gb/s EoS 1.645673 1.566932 0.008697

Round-trip signaling message propagation plus emission delay between GA SN16000 and NC SN16000: 0.025s

61

Conclusions• Need BA service if the per-call bandwidth allocation is a

significant fraction of link capacity (1Gbps on a 10Gbps link)• Key differentiator between BA and IR: BA calls specify call

duration• GMPLS control-plane protocols are designed for distributed

scalable implementation of IR service• GMPLS control-plane protocols do not have parameters to

support BA service (e.g., call duration in RSVP-TE)• BA service with centralized schedulers per domain suitable for

long call-duration eScience applications (small number of users) • To support BA service for general-purpose applications, e.g.,

large file transfers in Web, P2P, storage, CDN, with short call durations, need to design scalable control-plane solution for BA calls

• Four reasons to develop an IR service with moderate per-BW calls

Item 7: Related Items on Future Internet

• US National Science Foundation (NSF) interest– CyberPhysical Systems to create an "Internet of

Things“– "Network Science" – Ty Znati (Director of Computer Network Systems

division in the NSF's CISE directorate):http://www.csm.ornl.gov/workshops/NetworkingResearchChallenges/agenda.html

• GENI effort to build a global network for research:– http://www.geni.net/

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Documents

1 GMPLS optical networks Malathi Veeraraghavan Professor Charles L. Brown Dept. of Electrical & Computer Engineering University of Virginia [email protected]