Presented by Radha Gummuluri ECE-E 641 Fiber Optic Communications SONET Presented by Radha Gummuluri ECE-E 641 Fiber Optic Communications 9/18/2018 Radha Gummuluri

Topics What is SONET Frame Structure and Transmission Speed Standards Typical Sonet Connection and Sonet Network Elements Network Configurations Ring Architecture (Self Healing Rings) Advantages of SONET 9/18/2018 Radha Gummuluri

Sonet Overview Standard for Optical telecommunications Formulated by Exchange Carriers Standards Association (ECSA) for ANSI Defines the Optical Carrier (OC) levels and electrically equivalent synchronous transport signals (STS) Synchronous design allows efficient multiplexing of lower level STS signals into a higher level STS signal without bit stuffing. SONET/SDH is the primary backbone transmission technology for national and international carriers Today, there are over 150,000 SONET rings deployed in North America alone 9/18/2018 Radha Gummuluri

Frame Structure Standards Frame Structure of an STS-1 SONET frame Path overhead (1 column) Section and Synchronous Payload envelope Line (SPE) Overhead 9 rows of bytes 3 87 columns 90 columns STS-1 = (90 bytes/row)(9 rows/frame)(8 bits/byte)(125µs/frame) = 51.84Mb/s Frame Structure of an STS-N SONET frame Path overhead (N column) Section and Synchronous Payload envelope Line (SPE) Overhead 9 rows of bytes 3*N 87*N columns 90*N columns 9/18/2018 Radha Gummuluri

Transmission Speed Standards SONET OC level Electrical level Line rate Mb/s Capacity SDH OC-1 STS-1 51.84 28 DS1 or 1 DS3 - OC-3 STS-3 155.52 84 DS1 or 3 DS3 STM-1 OC-12 STS-12 622.08 336 DS1 or 12 DS3 STM-4 OC-48 STS-48 2488.32 1344 DS1 or 48 DS3 STM-16 OC-192 STS-192 9953.28 5376 DS1 or 192 DS3 STM-64 Small Enterprise Requires < 155Mbps of Bandwidth OC-12 SONET Ring OC-3 OC-192 SONET Ring Sonet terminology for Transmission distances Transmission Distance SONET terminology SDH terminology <= 2 km Short-reach Intra office 15 Km Intermediate-reach Short-haul 40km at 1310nm Long-reach Long-haul 80km at 1550nm 120km at 1550nm Very long-haul 160km at 1550nm Ultra long-haul OC-48 SONET Ring OC-12 Larger Enterprise Requires < 622Mbps of Bandwidth 9/18/2018 Radha Gummuluri

Typical Sonet Connection Add drop Multiplexer Digital Cross Connect (X-Connect) Regenerator Terminal Multiplexer PTE Path Terminal Equipment LTE Line Terminal Equipment LTE Line Terminal Equipment PTE Path Terminal Equipment Section Line Path Section Overhead Section error monitoring Provision of orderwire channel for voice communication Provision of data communication for OAM&P to facilitate network management Framing Line Overhead Path Overhead Consists of bytes for locating the SPE in the frame performance monitoring of STS-SPE Concatenating of signals path status byte for maintenance purpose Line performance and error monitoring path trace Automatic protection switching 9/18/2018 Radha Gummuluri

Network Configurations Point to Point PTE PTE reg Point to Multipoint PTE ADM PTE reg reg mux Hub Network Mu x Dc s mux mux 9/18/2018 Radha Gummuluri

SONET Rings (self healing rings) Unidirectional Path-Switched Ring (UPSR) 1 Primary path Node 1 Node 2 8 Protection Path 7 2 4 5 6 Node 4 Node 3 3 TX Primary path 1 1 4 5 Node 4 2 6 3 Protection path 3 2 RX 9/18/2018 Radha Gummuluri

Bidirectional Line-Switched Ring (BLSR) Primary bidirectional loop 4p Node1 5p 8p 1p 4s 5s 8s 1s Node 4 Node 2 Secondary bidirectional protection loop 7p 2p 6s 7s Node3 3s 2s 6p 3p 1 4 2 Protection switching loopbacks 3 9/18/2018 Radha Gummuluri

Advantages of Sonet SONET/SDH Network Defines a set of generic standards that enable products from different vendors to be connected. Facilitates adding and dropping of signals with a single multiplexer. Has a flexible architecture that is capable of accommodating future applications, with different transmission rates Reduces the equipment requirement and increases the network reliability. Presence of payload and overhead bytes, where the overhead bytes provide network management at various levels. IP IP 99.9% of all data traffic goes across the SONET network, including IP ATM SONET/SDH Network LAN Traffic (Ethernet) LAN Traffic (Ethernet) 9/18/2018 Radha Gummuluri

References: [1] “advances in optical switching and networking: past, present and future”, proceedings IEEE Southeast Con 2002 [2]”sonet: now it’s the standard optical network”, IEEE communications magazine, March 1989, volume 27, number 3 [3] synchronous Optical Networks (SONET) document by www.iec.org [4] sonet network elements document by www.tektronix.com/optical [5]”a class of self healing ring architectures for sonet network applications”, IEEE transactions on communications, vol 40, no. 11, nov.1992 9/18/2018 Radha Gummuluri

THANK YOU 9/18/2018 Radha Gummuluri