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Going Optical with Movaz - Building and Maintaining BiSON. Scot Colburn - NCAR WESTNET 2006. Three lessons: . Layer 3 is math, Layer 1 is Physics. Layer 3 uses math, statistical tricks to share a pipe WDM uses physics tricks to share a fiber
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Going Optical with Movaz -Building and Maintaining BiSON Scot Colburn - NCAR WESTNET 2006
Three lessons: • Layer 3 is math, Layer 1 is Physics. • Layer 3 uses math, statistical tricks to share a pipe • WDM uses physics tricks to share a fiber • Movaz – Relatively young company, recently acquired by Adva, sells “Heathkit” WDM nodes • BiSON – Bi-State Optical Network connecting Northern Colorado and Southern Wyoming. • Phases: GBICs, CWDM, DWDM, 10G • Motivation: BRIN, Lariat, TeraGrid, BPOP, FRGP. WestNet 2006
Networking moves down the stack “There is a theory which states that if ever anyone discovers exactly what the Universe is for and why it is here, it will instantly disappear and be replaced by something even more bizarre and inexplicable. There is another theory which states that this has already happened.” -Douglas Adams (1952 - 2001) WestNet 2006
Remember 10Base5? WestNet 2006
10Base5/2 begot Bridges, Routers • Broken or miscrimped connectors could break network, failures very difficult to locate • Had to put station taps precisely between nodes • Then, bridges divided L1 domains, increased manageability. L3 divided bridges. • 10BaseT fixed some of these multidrop issues by being point-to-point. WestNet 2006
WDM – “Physic”-al networking • Incredibly clear glass for optical fibers • Physical magic of EDFA (Erbium Doped Fiber Amplifier) • But EDFA’s generate ASE noise (Amplified Spontaneous Emission) • Inexpensive, high quality lasers • But jitter, modulation prevent high bit-rates • Single mode reduces dispersion • But bit-rates limited by CD and PMD • All rather unrelated to layer 3 experience • All engineering tricks to cope with physical realities WestNet 2006
New physical concepts, new terminology. And Telco terms, too • Electrical/Optical Engineering: • dBs, power, SNR, attenuation, EDFAs, ASE • Telco: • Tribs, Grooming, PMs, Alarms, BITS • In service upgrade? WestNet 2006
Aren’t ROADMs kinda bridges?Are MEMs cross connects kinda routers? • ROADMs (Reconfigurable Optical Add/Drop Multiplexers) will make optical simple, right? • Filter bands, equalize power, connect rings • MEMS cross-connects will let GMPLS really work, provision waves/paths almost the way PNNI provisioned SVCs, right? • WSS – Wavelength Selectable Switch WestNet 2006
Movaz WestNet 2006
Movaz OLD (Optical Line Driver) WestNet 2006
BLDR-MOVAZ-1> sh pm po 13-1 opt Port <1-1-13-1> Optical PMs Card Type: OLDUEV20 1310 Time: 1991/01/01 04:31:56 MDS PM OOR Value Low Threshold High Threshold Unit OPR OSC -33.7 -38.0 -6.0 dBm OPT OSC 1.9 0.0 4.0 dBm LBC OSC 7 - 60 mA EDFA IP -22.8 -25.0 -2.0 dBm EDFA GAIN 23.7 22.0 24.5 dB EDFA OP 2.3 - - dBm EDFA LPA 4 0 240 mW EDFA LBCA 28 0 800 mA EDFA LTA 25 20 30 degC EDFA LPB 19 0 120 mW EDFA LBCB 38 0 365 mA EDFA LTB 25 20 30 degC OPR -20.2 - - dBm OPT 0.8 - - dBm VOA ATTEN 1.7 - - dB Movaz OLD PM (Performance Monitoring) WestNet 2006
MOVAZ XCVR (Transceiver) WestNet 2006
Movaz UDS SIM WestNet 2006
Movaz Shelf WestNet 2006
BiSON – Bi State Optical Network WestNet 2006
BiSON history • Our Quest for fiber (chronological order) • Denver-Boulder from ICG for NCAR • Boulder-Fort Collins from ICG, PRPA for CSU • Laramie-Denver from Level3 for Uwyo • Laramie-Fort Collins to close Bison Ring • Bought McCleod fiber outright, CSU repairs it WestNet 2006
BiSON just kinda grew up • No WDM in first path • Cisco CWDM (powerful) GBIC • Movaz CWDM in second path (Bldr-CSU) • Movaz DWDM in third path (UWyo-Dnvr) • In fourth path, Movaz DWDM but the OSC doesn’t reach • No APE (Automatic Power Equalization) • VGA OLD or Raman OLD in our future? WestNet 2006
BiSON diagram WestNet 2006
BiSON ring design • UWyo proposed classic DWDM redundant wave per site. Very expensive. • Remember that CWDM bit? Would need upgrade • Instead, designed Layer 2 ring: • 2 GigEs connect each site to the next. • "If the only tool you have is a hammer, you tend to see every problem as a nail.“ - Abraham Maslow • In retrospect, UWyo’s design would’ve been nice • We have potential for L2 packet loops. • Bridged VLAN ring passes through four nodes with three different network administrators. WestNet 2006
Bison L3/L2 WestNet 2006
BiSON evolution • Layer 2 instability • Observed ~5000 arps/sec – switch console was quite sluggish. • FRGP’s connected M20 router was distressed • Ultimately, found unidirectional path on Movaz GigE • Solutions considered: • Rate-limit broadcasts? Not a good Layer2 solution • Rapid spanning tree? Now on by default • MAC level filters? Looping packets likely allowed • Wait for NLR’s L2 network to figure it out? • Eliminate L2 loops WestNet 2006
Next BiSON steps? • Wyoming adding spur to Cheyenne • CU renting 1GE for NLR access • Probably put 10G around ring for something • Must replace CWDM segment with DWDM • Bridged? No - Probably non-stop 10G waves • Or deploy dedicated 2.5 G (2xGE) waves • Like 10BaseT is point-to-point, maybe L3 GE links should also not be multi-drop? • Keep existing shared bridged vlans as inter-BiSON links? WestNet 2006
UWyo Everybody gets their own 2.5 Gbps wave CSU FRGP BPOP WestNet 2006
To make a Lambda redundant network • Must replace CWDM segment with DWDM • $107K estimated • “Replacement” BiSON waves cost $51K • Assuming SIMS are reused at Level3 • New waves cost $61.6K (= $51K + $10.6K) • UDC SIMs cost $5.3K – need two per wave WestNet 2006
10G wave add • Denver-Boulder next 10G is ~$40K cheap, because existing TeraGrid 10G blazed the trail • Rest of ring? • Need $107K for CWDM conversion • ~$45K for VGA amps for Laramie-Fort Collins • Need to ask Movaz for quote? WestNet 2006