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High Speed Optical Networks: An Evolution of Dependency November 2, 2001 Todd Sands, Ph.D WEDnet Project www.wednet.on.ca University of Windsor Latency • The result of an event in time that slows the transport or processing of information • E.g. Machine (processing) latency in microsecs (n =1.2) • E.g. Network latency in millisecs (x < 130 ms) • Optical transport max. = 300,000 km/sec • Physical parameters of the transport media • Convergence of voice, image and data in the path • Switched cells and packet network behaviours • Potential of WDM optically switched and SONET architectures OSI Reference Model – Networking 101 • • • • • • • Application Presentation Session Transport Network Data-link Physical When two computers communicate on a network, the software at each layer on one computer assumes it is communicating with the same layer on the other computer. e.g. For communication at the transport layers, that layer on the first computer has no regard for how the communication actually passes through the lower layers of the first computer, across the physical media, and then up through the lower layers of the second computer. Do we know the effects of latency! Suspect that the answer is yes! We see it every day! No. of processors, power requirements, processing capability, storage capacity, and the needs of research that use most facilities can be intensive. HPCS resources supplied and funded through a needs-based process, but this can also be because of research What about a GRID? Is it on the same path? Are we mindful of details, such as latency…with respect to one of the most fundamental parts of the GRID… THE NETWORK Do we know how computing resources connect to the outside world?…Maybe… Do we have any control over the “extranet”? Primary Network Interface To Machine Resources These switches provide Ethernet to ATM SONET WAN interfaces for TCP/IP traffic PACKETS VS. CELLS VS. FRAMES • Frames – used for larger data amounts over high-speed, low error rate links – 2,000 – 10,000 characters in size – Data corrections not link by link – Therefore link by link error checking impacts network latency greatly • Packets – used for smaller data amounts across lower speed, high error rate links – 128 – 256 (bytes) characters in size – Lower chances of error in each packet, small amounts re-transmitted – Prioritization through tagging of packets leads to QoS • Cells – very small amounts of data with sometimes no error checking – Highly reliable optical networks sometimes with no error checking – Up to 48 - 53 (bytes) characters in size – Small size allows for load balancing of traffic on network – No payload in cells, no transmission - full payload, then transmission – Uses ATM Adaptation Layers – AAL’s 1-5 for shaping the network Optical Carrier Designations • • • • • • OC-1/STS-1 OC-3 OC-12 OC-48 OC-192 OC-768 51.84 Mbps 155.52 Mbps 622.08 Mbps 2,488.32 Mbps 9,953.28 Mbps 39,813.12 Mbps SONET • digital hierarchy based on Optical Carriers (OC’s) • maximum t-speed of 39.81312 Gbps • defines a base rate of 51.84 Mbps = STS-1s • OC’s are multiples of the t-speed • defines Synchronous Transport Signals – STS’s and STS-3c = OC 3 = 155 Mbps Overheads • • SONET carries 8,000 frames per second, 810 characters in size (36 characters of overhead and 774 characters of payload Section Overhead includes: – STS channel performance monitoring – Data channels for management such as channel monitoring, channel administration, maintenance functions and channel provisioning – Performs functions necessary for repeaters, add drop multiplexers (ADMs), termination gear, and digital access and cross connect systems (DACS) • Line Overhead includes: – STS-1c performance monitoring – Data channel management, payload pointers, protection switching information, line alarm signals, and far-end failure to receive indicators • In addition to these overheads there are also Path overheads Optical Wave Division • WDM multiplies (up to 32 more times) the capacity of existing fibre spans – cross (wide)-band, narrow band or dense band transmission options • DWDM Red waves 1550, 1552, 1555 & 1557 nm • DWDM Blue waves 1529, 1530, 1532& 1533 nm • Now can support 100 wavelengths with each wavelength supporting a channel rate of up to 10 Gbps Local Area Access Architectures 1-Meg or xDSL Modem Services in Communities Alternate Carrier MANs also Interface Central CO for Access Nodes Access Routers 1 M M 1 M M G b E PVCs – on carriers network 1000 Mb GbE Router OC-12 ATM Off Ramps -WDM ATM Network – OC12-OC48 G b E System Processors and Interfaces 100 Mb- 1Gb Grid Access Node – GigaPoP? All PVCs (SVCs or PVPs) usually terminate on 1 or more Centralized Access Routers Most carrier PVCs are UBR with access at minimum OC48 speeds 2.4 Gb/sec Backbone may be optically switched with P.O.S on wavelengths using TCP/IP as the main transport protocol but getting direct access to it is the key! Direct access will also minimize latency and the synergistic effects of latency What does a 5 minute average measurement show us with MRTG? Network Protocol Stack Models (WAN with IP) PC 1MM DBIC 1MM Ethernet Switch Network (Catalyst) (ATM) LAC (SMS-1000) LNS IP IP PPP PPP PPPOE PPPOE Ethernet Ethernet Ethernet Ethernet Ethernet 10BaseT 1MM QAM 1MM QAM L2TP UDP UDP IP IP Ethernet LLC/SNAP (1483) LLC/SNAP (1483) LLC/SNAP (1483) LLC/SNAP (1483) AAL5 AAL5 AAL5 AAL5 SAR SAR SAR SAR ATM ATM ATM ATM 10BaseT L2TP ATM SONET/SDH SONET/SDH SONET/SDH SONET/SDH SONET/SDH Making a Call Video Video Television V-Room HDGH Television WEDnet uses WUC as a carrier such as Bell or METROnet with core gear LS1010 and 7200 series for ATM and IP routing WRH Western Campus V-Room LE25 LE25 LE25 OC3 S D LE 25 SMF 25 Mb ATM FVC VGATE IBM 8274 9 slot FVC V-room P-Tel Video University of Windsor Dial - up Shared H.261 ISDN Making a Call Video Video Television V-Room HDGH Television WEDnet uses WUC as a carrier such as a Bell or METROnet with core gear LS1010 and 7200 series for ATM and IP routing WRH Western Campus V-Room LE25 LE25 LE25 OC3 S D LE 25 SMF 25 Mb ATM FVC VGATE IBM 8274 9 slot FVC V-room P-Tel Video University of Windsor Dial - up Shared H.261 ISDN Making a Call Video Video Television V-Room HDGH Television WEDnet uses WUC as a carrier such as Bell or METROnet with core gear LS1010 and 7200 series for ATM and IP routing WRH Western Campus V-Room LE25 LE25 LE25 OC3 S D LE 25 SMF 25 Mb ATM FVC VGATE IBM 8274 9 slot FVC V-room P-Tel Video University of Windsor Dial - up Shared H.261 ISDN Codec Negotiation Video Video Television V-Room HDGH Television WEDnet uses WUC as a carrier such as a Bell or METROnet with core gear LS1010 and 7200 series for ATM and IP routing WRH Western Campus V-Room LE25 LE25 LE25 OC3 S D LE 25 SMF 25 Mb ATM FVC VGATE IBM 8274 9 slot FVC V-room P-Tel Video University of Windsor Dial - up Shared H.261 ISDN Successful Call Video Video Television V-Room HDGH Television WEDnet uses WUC as a carrier such as a Bell or METROnet with core gear LS1010 and 7200 series for ATM and IP routing WRH Western Campus V-Room LE25 LE25 LE25 OC3 S D LE 25 SMF 25 Mb ATM FVC VGATE IBM 8274 9 slot FVC V-room P-Tel Video University of Windsor Dial - up Shared H.261 ISDN Making an ISDN Call Video Video Television V-Room HDGH Television WEDnet uses WUC as a carrier such as a Bell or METROnet with core gear LS1010 and 7200 series for ATM and IP routing WRH Western Campus V-Room LE25 LE25 LE25 OC3 S D LE 25 SMF 25 Mb ATM FVC VGATE IBM 8274 9 slot FVC V-room P-Tel Video University of Windsor Dial - up Shared H.261 ISDN Making an ISDN Call Video Video Television V-Room HDGH Television WEDnet uses WUC as a carrier such as a Bell or METROnet with core gear LS1010 and 7200 series for ATM and IP routing WRH Western Campus V-Room LE25 LE25 LE25 OC3 S D LE 25 SMF 25 Mb ATM FVC VGATE IBM 8274 9 slot FVC V-room P-Tel Video University of Windsor Dial - up Shared H.261 ISDN Making an ISDN Call Video Video Television V-Room HDGH Television WEDnet uses WUC as a carrier such as a Bell or METROnet with core gear LS1010 and 7200 series for ATM and IP routing WRH Western Campus V-Room LE25 LE25 LE25 OC3 S D LE 25 SMF 25 Mb ATM FVC VGATE IBM 8274 9 slot FVC V-room P-Tel Video University of Windsor Dial - up Shared H.261 ISDN Making an ISDN Call Video Video Television V-Room HDGH Television WEDnet uses WUC as a carrier such as a Bell or METROnet with core gear LS1010 and 7200 series for ATM and IP routing WRH Western Campus V-Room LE25 LE25 LE25 OC3 S D LE 25 SMF 25 Mb ATM FVC VGATE IBM 8274 9 slot FVC V-room P-Tel Video University of Windsor Dial - up Shared H.261 ISDN Codec Negotiation Video Video Television V-Room HDGH Television WEDnet uses WUC as a carrier such as a Bell or METROnet with core gear LS1010 and 7200 series for ATM and IP routing WRH Western Campus V-Room LE25 LE25 LE25 OC3 S D LE 25 SMF 25 Mb ATM FVC VGATE IBM 8274 9 slot FVC V-room OC3 P-Tel Video DEC Gigaswitch 18 gbps Dial - up Shared H.261 ISDN University of Windsor Video Television Leamington District Memorial Hospital Centrex module Successful Call Video Video Television V-Room HDGH Television WEDnet uses WUC as a carrier such as a Bell or METROnet with core gear LS1010 and 7200 series for ATM and IP routing WRH Western Campus V-Room LE25 LE25 LE25 OC3 S D LE 25 SMF 25 Mb ATM FVC VGATE IBM 8274 9 slot FVC V-room P-Tel Video Dial - up Shared H.261 ISDN University of Windsor Video Television Leamington District Memorial Hospital Centrex module AT&T and Regional Gigapop IP Architecture CA*net3 AT&T Gigapop BGP AT&T Route Server ATM /w SVC Regional IGP OCRINet /wOHI AT&T Network Regional IGP WEDNet Regional IGP SureNet CA*Net AS iBGP ATM interconnectivity Router / RFC1577 Client LAN interconnect AT&T AS iBGP Bhavani Krishnan From LAN to WAN This server and control facility houses multiple Digital Alpha, DEL PowerEdge, IBM Netfinity and RS/6000 servers. Located at a single campus the facility supports 400 nodes locally and 800 nodes 7.5 km away. SVCs are provisioned on separate PVPs for security and LANE services provide VLANs for ADT systems, pharmacy, and document imaging. The systems use GUI interfaces to assist visual references for end-users In the Ideal World! Dark fibre between nodes Homogenous switched architecture with minimal breakouts Low latency at all layers We will likely be dealing with something much different, unless there is about $500 M available to support and sustain the network side of grids to help minimize the synergistic effects of latency on applications Latency studies are important and the synergy of latency effects are important from the processor to the I/O architectures, to the network layers If commercial carriers are to be used anywhere in the path, latency should become a factor for selecting them as providers Effective monitoring and support of the extranet is important to the success of a GRID unless the GRID middleware can accommodate different types of latency and the variation that exists Internet routing is “best effort” with variable paths every time – not likely the best GRID platform Research networks like CA*net 3, Internet 2, ORION, etc. are the next best bet! However, the last mile issue still has to be addressed. The Future • “It is conceivable that future Internet networks may be a seamless composite of a variety of transport protocols. An Optical Internet might be used for high volume, best efforts computer to computer traffic, while IP over ATM might be used to support VPNs and mission critical IP networks, while IP over SONET would be used to aggregate and deliver traditional IP network services that are delivered via T1s, DS3s, and Gigabit uplinks” • From, Dr. Bill St. Arnaud, CANARIE