I Figure 7-4: Leased Line Speeds, Continued SONET/SDH Speeds Line Speed(Mbps) Typical Transmission Medium OC3/STM1 155.52 Optical Fiber OC 12/STM4 622.08 Optical Fiber OC48/STM16 2,488. 32Optical Fiber OC 192/STM64 9, 953.28 Optical Fiber OC768/STM256 39, 813.12 Optical Fiber For speeds above 50 Mbps, the world uses one technology Called soneT in the United States, sdh in Europe SONET speeds measured in OC numbers, SDH in STM numbers Speeds are multiples of 51. 84 Mbps Used mostly by carriers
7-11 Figure 7-4: Leased Line Speeds, Continued Line Speed (Mbps) Typical Transmission Medium OC3/STM1 155.52 Optical Fiber OC12/STM4 622.08 Optical Fiber SONET/SDH Speeds OC48/STM16 2,488.32 Optical Fiber OC192/STM64 9,953.28 Optical Fiber OC768/STM256 39,813.12 Optical Fiber For speeds above 50 Mbps, the world uses one technology Called SONET in the United States, SDH in Europe SONET speeds measured in OC numbers, SDH in STM numbers Speeds are multiples of 51.84 Mbps Used mostly by carriers
Public switched data Networks(PsDNs)
Public Switched Data Networks (PSDNs)
Figure 7-6: Public Switched Data Networks (PSDNS) Recap: Leased Line Data Networks Use many leased lines, which must span long distances between sites This is very expensive Company must design and operate its leased line network Public Switched Data Networks Carrier does more of the operational and management work Total cost of technology, service, and management usually lower than leased line networks 7-13
7-13 Figure 7-6: Public Switched Data Networks (PSDNs) • Recap: Leased Line Data Networks – Use many leased lines, which must span long distances between sites – This is very expensive – Company must design and operate its leased line network • Public Switched Data Networks – Carrier does more of the operational and management work – Total cost of technology, service, and management usually lower than leased line networks
I Figure 7-7: Public Switched Data Network(PSDN) Site A Site B POP POP Public Sw itched Data Netw ork(PSDN) Point of Presence( pOP( PoP One Private Line access Line per Site In Public switched data Networks the Psdn carrier handles all switching Reduces the load on the network staff The psdn central core is shown as a cloud to indicate that the user firm does not Site E have to know how the network operates 7-14
7-14 Figure 7-7: Public Switched Data Network (PSDN) Site A Site B Site C Site D One Private Line Access Line per Site Public Sw itched Data Netw ork (PSDN) Site E POP POP POP Point of Presence POP In Public Switched Data Networks, the PSDN carrier handles all switching. Reduces the load on the network staff. The PSDN central core is shown as a cloud to indicate that the user firm does not have to know how the network operates
I Figure 7-7: Public Switched Data Network(PSDN) Site A Site B POP POP Public Sw itched Data Netw ork(PSDN) Point of Presence( pOP( PoP One Private Line access Line per Site In public switched data Networks the customer needs a single leased line from each site to one of the psdn carrier's Site E points of presence(POPs) 7-15
7-15 Figure 7-7: Public Switched Data Network (PSDN) Site A Site B Site C Site D One Private Line Access Line per Site Public Sw itched Data Netw ork (PSDN) Site E POP POP POP Point of Presence POP In Public Switched Data Networks, the customer needs a single leased line from each site to one of the PSDN carrier’s points of presence (POPs)