Educational Information

SONET/SDH Digital Hierarchy

Optical Level Electrical Level Line Rate (Mbps) Payload Rate (Mbps) Overhead Rate (Mbps) SDH Equivalent
OC-1 STS-1 51.840 50.112 1.728 -
OC-3 STS-3 155.520 150.336 5.184 STM-1
OC-9 STS-9 466.560 451.008 15.552 STM-3
OC-12 STS-12 622.080 601.344 20.736 STM-4
OC-18 STS-18 933.120 902.016 31.104 STM-6
OC-24 STS-24 1244.160 1202.688 41.472 STM-8
OC-36 STS-36 1866.240 1804.032 62.208 STM-13
OC-48 STS-48 2488.320 2405.376 82.944 STM-16
OC-96 STS-96 4976.640 4810.752 165.888 STM-32
OC-192 STS-192 9953.280 9621.504 331.776 STM-64
OC-768 STS-768 39818.120 38486.016 1327.104 STM-256

OC-9, OC-18, OC-24, OC-36, OC-96 are considered orphaned rates.    

Tutorials and General Backgrounders

Tektronix: A good tutorial.  


Turning Up and Testing a Six Node SONET Ring

Understanding UPSRs

Uderstanding BLSRs


Sonet Sync:  A guide to sonet ring synchronization with practical examples of how sync messaging and sync auto reconfig are used.



SDH Primer  [Tektronix]

Metro Ethernet, Optical Modules

Pluggable Optical Modules - A brief overview of pluggable technology [XENPAK, SFP, XFP, XAUI] 

10 Gigabit Ethernet - A short discussion of LAN/WAN PHY, LX4 and LRM standards and GE  nomenclature 

Delay Limitations When Extending Metro Ethernet  Into The Wide Area

Diffential Delay in Ethernet over SONET Networks

DWDM And Optical Networking

WSS: Understanding Degrees of Freedom, the wavelength selective switch, ROADMs and WXCs

Understanding EDFAs, Erbium Doped Fiber Amplifiers

ITU Grid for 50GHz and 100GHz channel spacing for  long, conventional, and short wavelength bands

MONET - Multiwavelength Optical Networking Project.  


Network Management

SONET DCC: A great primer on OSI and ip sonet DCC internetworking

SONET DCN: [19MB] A niffty paper describing the Data Communications Network used for network management and an OSI to IP migration path. Marben 

Other Links

Cell-Relay Retreat A fantastic source for mostly ATM information.

Web Pro Forum  There is a lot of stuff here, some of which is linked to on this page.

The Glass Menagerie This is Cornings Web Site.  I have link as well as well as on the vendor page because there is a lot of good stuff here on fiber and how to characterize it.  They make you register so I can't link to it directly.

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