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GMPLS Optical Networks - University of Virginia

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					GMPLS optical networks
Malathi Veeraraghavan
Professor Charles L. Brown Dept. of Electrical & Computer Engineering University of Virginia mvee@virginia.edu

ETRI, Korea Feb. 2009
GMPLS: Generalized MultiProtocol Label Switched networks (MPLS, SONET, WDM, SDM, VLAN)
1

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
2

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

IP

Circuit technologies: time/frequency division multiplexing PDH: T1, T3 switch: Digital Cross Connect (DCS) SONET/SDH: OC3-OC768 Switch: SONET/SDH crossconnects DWDM: OTU1-OTU3 Switch: optical WDM crossconnects

Packet technologies: virtual circuit switches

ATM

MPLS

Carrier-grade Ethernet

All the above: Data-plane technologies

3

IP and leased line service deployment
Leased line
Circuit or virtual circuit (VC) switch Telco service provider (transport network) owns circuit/VC switches

Internet service provider or enterprise owns IP routers

IP Router

Management plane (in transport network)
(1) Admins use Web interface to request leased line creation Network management system
Customer edge device

(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

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

Spectrum of services
New service: rapid provisioning

Leased line

Verizon Bandwidth-on-Demand (BoD)

IP

6

Management plane + control plane
(1) Admins use Web interface to request leased line creation (3) TL1/CLI to edge node Network management system
Customer edge device

(2) NMS still computes path with available bandwidth

(4) hop-by-hop distributed signaling for circuit/VC provisioning
Customer edge device

Customer edge device

Customer edge device

Customer edge device

switch controllers have RSVP-TE software

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

Scheduler

(2) scheduler computes path with available bandwidth

(3) TL1/CLI to edge node
external controller

(4) hop-by-hop distributed signaling for circuit/VC provisioning

(3a)

Enterprise

switch controllers have RSVP-TE software (3a) configure router to filter packets for long flow on to circuit/VC

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

Spectrum of services
New services
Leased line
Verizon BoD
eScience

10G POTS

IP

Book-ahead (BA) mode • call duration specified Current solution: • centralized per-domain path computation/admission control Low call handling volume OSCARS/DRAGON

Plain Old Telephone Service (64kbps) Immediate-Request (IR) mode • unspecified call duration Low call setup overhead ( holding times can be shorter) Distributed path computation/admission control High call handling volume CHEETAH
11

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
12

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
13

• DRAGON focus:
– For eScience

Key difference between DRAGON and CHEETAH

• 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
14

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

Types of switches
Multiplexing technique on data-plane links Admission control in control plane? Circuit Packet switch (PS) switch (CS) - header based - position based (port, time, lambda)

Connectionless (CL) - no admission control
Connection-oriented (CO) - admission control

Not an option

e.g., Ethernet

e.g., Virtual-circuit telephone e.g., MPLS, ATM, SONET PBBTE WDM, SDM
16

GMPLS network switches

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
17

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

18

IR mode: M/G/m/m ErlangB formula
  
Pb 

 m / m!
k 0

  / k!

m k

(1  Pb )   ub  m

: offered traffic load in Erlangs : call arrival rate 1/: mean call holding time /m: per-server traffic intensity m: number of circuits Pb: call blocking probability ub: utilization

For a 1% call blocking probability, i.e., Pb = 0.01
 1 10 100 m 4 17 117 ua 24.8% 58.2% 84.6%
If m is small, high utilization can only be achieved along with high call blocking probability
19

Comparison of Immediate-Request (IR) and Book-Ahead (BA) schemes
• 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 probability less than 20%
• BA-First schemes are needed when m < 32

U: utilization K: number of time periods in advance-reservation window IR m=10, U = 80%: PB = 23.6%
m=100, U = 80%: PB = 0.4%

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

BA m=10, K=10, U = 80%: PB = 0.4%
20

Bandwidth sharing mechanisms in GMPLS networks
Needed if per-call Bandwidth sharing mechanisms circuit rate is a large fraction of link capacity (e.g., 1Gbps circuits on a 10Gbps link, m = 10) Book-ahead Immediate-request call duration specified unspecified call duration

BA-n/BA-First
session-type requests: BW, duration

VBDS (Varying-Bandwidth Delayed Start)
data-type requests: file size (can assign any rate, even vary rate in different time ranges)

BA-n
Users specify a set of n call-initiation time options

BA-First
Users are given first available timeslot

X. Zhu, Ph.D. Thesis, UVA, http://www.ece.virginia.edu/mv/html-files/students.html 21

Relate BW sharing modes to network types
Bandwidthsharing mechanisms eScience networks (small number of users) Book-Ahead (BA) (high rate per call) 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) 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) Immediate-Request (IR) (moderate rate per call) What applications? Centralized control-plane (DRAGON)

general-purpose networks (large number of users)

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

22

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

23

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 moderaterate circuits that can support a brand new class of applications • economic value for the networking industry 3. 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 time

24

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.
25

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

Outline
• Cheetah vs. Dragon Approach
– Theoretical concepts

GMPLS networks
– Technologies, off-the-shelf switches, controlplane protocols

• State of the art on different applications & networks
– Commercial – Research-and-Education (REN) networks
27

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
28

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
29

Off-the-shelf GMPLS switches
Vendor/system Cisco 12000 series Juniper T640 Data-plane MPLS switching; PWE3 Ethernet-over-MPLS MPLS switching; PWE3 Ethernet-over-MPLS Control-plane RSVP-TE, OSPF-TE RSVP-TE, OSPF-TE

Sycamore SN16000

SONET switching; GFP/VCAT Ethernet-overSONET (EoS)
SONET switching; GFP/VCAT EoS WDM switching; G.709 Eth-over-WDM SDM switching; Ethernet-over-fiber Ethernet VLAN switching

RSVP-TE, OSPF-TE for SONET circuits; no support for EoS
Proprietary signaling/routing protocols RSVP-TE, OSPF-TE RSVP-TE, OSPF-TE (?) None
30

Ciena CDCI Movaz (now Adva) RayExpress Calient Force10 E600

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 intradomain path computation

• Not a scalable solution to support short-duration, high-BW calls
32

Outline
• Cheetah vs. Dragon Approach
– Theoretical concepts

• GMPLS networks
– Technologies, off-the-shelf switches, controlplane protocols

State of the art on different applications & networks
– Commercial – Research-and-Education (REN) networks
33

Spectrum of services
New services
Leased line
Verizon BoD eScience

10G POTS

IP

34

Commercial uses
• Semi-permanent MPLS virtual circuits
– Traffic engineering – Voice over IP
• QoS concerns: telephony has a 150ms oneway 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
35

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
36

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

37

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

38

Spectrum of services
New services
Leased line
Verizon BoD
eScience

10G POTS

IP

Book-ahead (BA) mode • call duration specifie d Current solution: • centralized per-domain path computation/admission control Low call handling volume OSCARS/DRAGON
39

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)

40

Internet2 DWDM network

Infinera DWDM system
http://events.internet2.edu/speakers/speakers.php?go=people&id=178 Rick Summerhill talk (10/11/2007)
41

Internet2 Dynamic Circuit (DC) network

Ciena CD-CI Eth-SONET switch
http://events.internet2.edu/speakers/speakers.php?go=people&id=178 Rick Summerhill talk (10/11/2007)
42

Internet2 IP-routed network
IP-router-to-router links on one wavelength SONET switch-to-switch links on another wavelength

Ciena CD-CI Eth-SONET switch Juniper T640 IP router
http://events.internet2.edu/speakers/speakers.php?go=people&id=178 Rick Summerhill talk (10/11/2007)
43

Equipment at each PoP

http://events.internet2.edu/speakers/speakers.php?go=people&id=178 Rick Summerhill talk (10/11/2007)

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
http://www.csm.ornl.gov/workshops/NetworkingResearchChallenges/agenda.html Talk by Tom Lehman, Sep. 28, 2008 46

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

http://dragon.east.isi.edu

47

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

http://www.csm.ornl.gov/workshops/NetworkingResearchChallenges/agenda.html Talk by Tom Lehman, Sep. 28, 2008 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
http://www.csm.ornl.gov/workshops/NetworkingResearchChallenges/agenda.html Talk by Tom Lehman, Sep. 28, 2008 49

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

http://www.csm.ornl.gov/workshops/NetworkingResearchChallenges/agenda.html Talk by Tom Lehman, Sep. 28, 2008 50

Heterogeneous Network Technologies Complex End to End Paths
Example: DRAGON
AS 1 IP Control Plane AS 2

Example: Internet2 DC Example: ESNet SDN
AS 3 IP Control Plane

IP Control Plane

VLSR
Ethernet over SONET Ethernet Lambda Switch SONET Switch Router 51 Router MPLS LSP End System Ethernet Segment VLSR Established VLAN

VLSR

Ethernet over WDM End System

Ethernet Segment VLSR Established VLAN

http://events.internet2.edu/speakers/speakers.php?go=people&id=178 Rick Summerhill talk (10/11/2007)

IDCP operation
Route selection, admission control centralized per domain at IDC

•

• •

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

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 CDCI, which initiates proprietary hop-by-hop signaling to configure circuit through subnet

53

GOLE: GLIF open lightpath exchange

54

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
55

Spectrum of services
New services
Leased line
Verizon BoD
eScience

10G POTS

IP

Plain Old Telephone Service (64kbps) Immediate-Request (IR) mode • unspecified call duration Low call setup overhead ( holding times can be shorter) Distributed path computation/admission control High call handling volume CHEETAH
56

NSF-funded CHEETAH network GbEthernet and SONET
UVa TN PoP SN16000
OC192 Control GbE/ 10GbE card card card GbE GbE

CUNY NCSU
GbE

End hosts

GbEs

OC-192 GA PoP SN16000 NC PoP SN16000
OC192 Control GbE/ GbE 10GbE card card End card
GbE

End

GbE GbE/ Control OC192 10GbE card hosts cards card

hosts

ORNL

GbE

OC-192
Sycamore SN16000 SONET switch with GbE/10GbE interfaces

GaTech

57

Networking software
• Sycamore switch comes with built-in GMPLS control-plane protocols: • We developed CHEETAH software for Linux end hosts: – circuit-requestor
– RSVP-TE and OSPF-TE

– CircuitTCP (CTCP) code

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

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

58

CHEETAH network usage
End Host CHEETAH software DNS client RSVP-TE module CHEETAH software DNS client RSVP-TE module End Host

IP-routed network

Application TCP/IP CTCP/IP

SONET circuitswitched network

Application TCP/IP

NIC 1 NIC 2

Circuit Gateway

Circuit Gateway

NIC 1 NIC 2

CTCP/IP

• Bandwidth-sharing mode:
• • •

• Applications:
• •

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 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 59

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
Circuit type End-to-end circuit setup delay (s) 0.166103 0.165450 1.645673 Processing delay for Path message at the NC SN16000 (s) 0.091119 0.090852 1.566932 Processing delay for Resv message at the NC SN16000 (s) 0.008689 0.008650 0.008697

OC-1 OC-3 1Gb/s EoS

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

•

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 60

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
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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/NetworkingResearch Challenges/agenda.html

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

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