Figure 7-1: Wide Area Networks WANS) Carriers Beyond their physical premises, companies must use the services of regulated carriers for transmission Companies do not have rights of way to lay wires beyond their premises Customers are limited to whatever services the carriers provide Prices for carrier services change abruptly and without technological reasons Prices and service availability vary widely from country to country 7-6
7-6 Figure 7-1: Wide Area Networks (WANs) • Carriers – Beyond their physical premises, companies must use the services of regulated carriers for transmission • Companies do not have rights of way to lay wires beyond their premises – Customers are limited to whatever services the carriers provide – Prices for carrier services change abruptly and without technological reasons – Prices and service availability vary widely from country to country
Leased Line Networks
Leased Line Networks
Leased Lines: Recap Leased line characteristics Point-to-point circuits Always on High speeds: 64 kbps (rare) to several gigabits per second Leased for a minimum period of time Usually offered by telephone companies 7-8
7-8 Leased Lines: Recap • Leased Line Characteristics – Point-to-point circuits – Always on – High speeds: 64 kbps (rare) to several gigabits per second – Leased for a minimum period of time – Usually offered by telephone companies
Figure 7-2: Leased Line Networks for Voice and Data eased Line voice Network Site A Site B OC3 Leased Line PBⅩ PBX Leased T1 Line Leased Leased line voice Networks Have a 56 kbps Site C Leased PBX at each Site Line 56 kbps PBX Leased Ine Leased 56 kbps Line PBX PBX Leased Line Site D Site e 7-9
7-9 Figure 7-2: Leased Line Networks for Voice and Data OC3 Leased Line T1 Leased Line T1 Leased Line T3 Leased Line 56 kbps Leased Line 56 kbps Leased Line 56 kbps Leased Line Site A Site B Site D Site E Site C Leased Line Voice Network PBX PBX PBX PBX PBX Leased Line Voice Networks Have a PBX at Each Site
Figure 7-2: Leased Line Networks for Voice and Data eased Line data Network Site a Site B 田 outer OC3 Leased Line Router Leased T1 Line Leased line data Networks Have a 56 kbps Site C Router at each Site Leased Line Router Leased 56 kbps Ine Leased Router/56 kbps Line Leased Router Line Site D ite e 7-10
7-10 Figure 7-2: Leased Line Networks for Voice and Data OC3 Leased Line T1 Leased Line T1 Leased Line T3 Leased Line 56 kbps Leased Line 56 kbps Leased Line 56 kbps Leased Line Site A Site B Site D Site E Site C Leased Line Data Network Router Router Router Router Router Leased Line Data Networks Have a Router at Each Site