Optical Network

Optical Networks Mithilesh Pamnani Chiranjib Dhar Shoaib Naik Prabhat Singal Abhishek Singh Nagalakshmi S

What is Optical Network? • Optical networks are high-capacity telecommunications networks based on optical technologies and components that provide routing, grooming, and restoration at the wavelength level as well as wavelength-based services • It uses Optical Fibers for data transmission

FTTH

- why did it come into picture

• As the quality of the optical fibre was improving, efficient transmitters and receivers appeared, it seemed possible to build an access network that would be based on the optical technology.

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• Due to the lack of active units in light path, the architecture of system was simple, cost effective offered bandwidth that was not, still is not, possible to achieve other access methods. •

the the and and by

History n n n

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In 1950’s scientists developed glass fibers that included a separate glass coating In 1957, Gordon Gould popularized the idea of using lasers In 1970, Drs. Robert Maurer, Donald Keck, and Peter Schultz succeeded in developing a glass fiber that exhibited attenuation at less than 20 dB/km In the early 1970’s, the U.S. Navy installed a fiber optic telephone In 1977, AT&T installed fiber optic telephone systems in Chicago and Boston respectively At the 1994 Winter Olympics in Lillehammer, Norway, fiber optics transmitted the first ever digital video signal In 1998, researchers transmitted 100 simultaneous optical signals, each at a data rate of 10 gigabits (giga means billion) per second for a distance of nearly 250 miles (400 km) The important factor in these developments is the increase in fiber transmission capacity, which has grown by a factor of 200 in the last decade

Comparison with other media

Transmission Capacity

Bandwidth - Scalability

Advantages of Optical Fiber •

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Enormous bandwidth.

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Less susceptible to signal degradation than copper wire.

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Less weight.

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Data can be transmitted digitally.

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Lower-power transmitters can be used instead of the high-voltage electrical transmitters used for copper wires.

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No Crosstalk.

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Because no electricity is passed through optical cable it is nonflammable, and immune to lightning.

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High Signal Security. Difficult to tap signal from optical cable

Disadvantages • Fibre optics are that the cables are expensive and difficult to install(But cost can be reduced when installed over long distances) •

• The termination of a fibre optics cable is complex and requires special tools. •

• They are more fragile than coaxial cable.

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Types Of Optical Networks • There are basically two broad categories of optical networks – •

– Passive Optical Networks (PON) • •

– Active Optical Networks (AON)

GPON • The need for larger bandwidths and the unquestionable complexity of ATM forced a revised approach an hence new standard called GPON3 was released in 2003. • Uses Generic framing procedure and not ATM • Provides both voice and data oriented services • Transfer rates of up to 2.48 Gbps in the downstream as well as the upstream direction. •

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Ethernet PON ( EPON ) • Released in September 2004 with a main goal to achieve a full compatibility •

NEXT GENERATION OF ACCESS NETWORKS •

WAVELENGTH DIVISION MULTIPLEXING ACCESS PASSIVE OPTICAL NETWORKS

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– Ultimately, they can offer the largest bandwidth at the lowest cost – The architecture of WDM PON is similar to PON. The main difference is that ONUs operate on different wavelengths and hence higher transmission rates can be achieved – Requires manual reconfiguration which significantly increases the cost of maintenance – The disadvantage of WDM PONs is the high cost of equipment •

WAVELENGTH DIVISION MULTIPLEXING TIME DIVISION MULTIPLEXING PASSIVE OPTICAL NETWORKS • Developed in an attempt to serve more customers. • A hybrid of both WDMA and TDMA Less complex and expensive equipment was needed than in WDM PONs with a similar number of connected customers •

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Comparison of different FTTH architectures

PON (Passive Optical Network)

Different Topologies

Network Topologies with PON

AON (Active Optical Network)

Network Topologies with AON

AON vs PON

Comparison - AON vs. PON • – • • • • • • • • • • •

Bandwidth Security and quality of services Business case aspects Investment costs (CAPEX) comparison Operating expenses (OPEX) comparison Flexibility and scope for usage Summary

Bandwidth

Bandwidth

Security and quality of services

Security and quality of services

Security and quality of services

Security and quality of services

Business case aspectsInvestment costs (CAPEX)

Comparison of operating expenses (OPEX)

Flexibility and scope for usage

Summary

Summary

GPON-ENCAPSULATION

EPON Vs. GPON  PARAMETER

EPON

GPON

Standard

IEEE803.2ah

ITU-TG.984

Bandwidth

Symmetric 1Gbps

Downstream 1.25-2.5Gbps Upstream 155Mbps-2.5Gbps

Downstream Efficiency

72% 8B/10B encoding (20%) Overhead & Preamble (8%)

92% NRZ scrambling (no encoding) Overhead (8%)

Revenue BW

900 Mbps

2300 Mbps

Transmission

Ethernet

ATM, Ethernet, TDM

EPON Vs. GPON cntd..  PARAMETER

EPON

GPON

Split ratio

1:32

1:64, (1:128 planned)

Security

None specified. AES used by various vendors.

128-bit AES is part of the standard.

Interoperability

None specified

FSAN and ITU-T

Network Management

OAM&P OAM is optional and minimally supports: failure indication, loop-back and link monitoring to the ONT. No Prioritization Provisioning and services are out of scope.

OMCI is mandatory. Full FCAPS on ONT and services.

QoS

Fragmentation for HighPriority Packets

Fragmentation for HighPriority Packets

GPON/EPON Framing

DEPLOYMENT OF OPTICAL N/W S • Fiber To The Home (FTTH) deployments continue to enjoy accelerated growth worldwide • • Alcatel-Lucent is engaged in over 95 FTTH projects around the world, over 80 of which are with GPON (as-of Q2, 2009)

USAGE ACROSSS THE WORLD BPON - GPON • The United States (Verizon, Calix) • The UK •

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EPON • Japan (Nippon Telegraph and Telephone Corporation [NTT]) • Korea (Korea Telecom) • China (Huawei, ZTE) •

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TDM PON • B-PON, E-PON, and G-PON are close derivatives of the original TDM PON concept. • The IEEE 802.3 Ethernet PON (EPON or GEPON) standard was completed in 2004 • EPON 802.3 Ethernet frames with symmetric 1 gigabit per second upstream and downstream rates • Drift from EPON to GPON because GPON supports triple play

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IMPORTANCE OF PON •

• Bandwidth will be much more higher then copper line connection so we will have access to internet much more faster • Low OPEX and CAPEX • No active components-which translates into low maintenance and replacement costs • Competitive pricing • PON provides a faster connection to internet because of this large firms profits more because time is money

GPON • Gigabit PON • It is an evolution of the BPON standard • It is a PON technology operating at bitrates of above 1 Gb/s • It supports higher rates, enhanced security, and choice of Layer 2 protocol (ATM, GEM, Ethernet) • worldwide gigabit passive optical network (GPON) deployments have increased sevenfold- Dell’Oro Group.

WDM PON • WDM-PONs can serve distances up to 80–100 km without the need for optical amplification in addition to blistering b/w

• • The other advantage of WDM-PON is a huge increase in the potential number of endusers served.

• • The high cost of WDM-PON equipment is still a major stumbling block to widespread deployment

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NORTH AMERICA • Calix- leader in the fast-growing GPON fiber-fed mobile backhaul • Telecom provider CenturyLink (CenturyTel Inc.) has selected the new Calix 766GX, 766GX-R, and 765G-R GPON optical network terminals (ONTs) for fiber-fed mobile backhaul services in 33 states. • Broadcom – come up with optical network chips • Verizon - to introduce an advanced FTTP architecture •

• Nortel –LG JV, acquired WDM-PON equipment maker Novera Optics in August 2008.

• • German metro specialist ADVA Optical Networking entering the market with a product that exploits coarse WDM in September 2008

• • Cable operators and other CLECs using GPON for business services have been able to compete very effectively for small- and medium-size businesses, as well as for backhaul to cellular sites • •

EUROPE • Nokia Siemens Networks eschewing existing PON technology- in favor of WDM-PON.

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• Tellabs is concentrating on WDM-PON through its involvement in its research project, drifting away from GPON

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• Nortel announced in September that UNET will deliver high-speed internet for homes and businesses in the Netherlands using its WDMPON solution

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• WDM-PON is still not standardized, and that

KOREA • Proxim Wireless Corporation -quadruple play, announced its new 4G Backhaul product lines -- the Tsunami™ QB-8100 point-topoint (PtP) and the Tsunami™ MP-8100 pointto-multipoint (PtMP).

• • Exceeds the ITU requirements for 4G throughput speeds

• • High performance and very low latency over long distances, eliminating expensive recurring leased line charges

JAPAN • • More than 10 million fiber-to-the-home (FTTH) subscribers • • Alcatel-Lucent -Suo Cable deploying GPONthe first commericial GPON deployment in Japan • • Result in speeds around 2.5 GBPS

INDIA •

• Bharti Airtel and BSNL are looking to switch over to GPON by the end of 2010

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• Challenges :

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• Cost associated with gaining permission to build new ducts and lay the fiber

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• Gaining access to buildings - one that could lead to high-speed broadband

CHINA • ZTE unveiled a WDM-PON prototype – commercialization before the end of 2009 •

• CNC China selected the Gigabit PON (ITU-T G.984.x) GPON Optimate platform from FlexLight Networks, Inc

• • Optimate - economical Gigabit PON (GPON) solution- economical triple play

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• Access over a single fiber access

Future development of PON • In Japan, the PON market is well established and growing at a rate of 300% year to year • • By comparison DSL is growing 150% year to year in the U.S. • • Top companies like Verizon, SBC and Bell South have all announced some type of PON deployment • • The PON market in North America is just starting to emerge • • Industry analysts expect an equally large take rate by North American consumes •