1 VPNs & Specialized Network Services Virtual private networks –Lowering the cost of enterprise links & enabling remote access Frame relay as a replacement for private lines T-1/E-1 the first high speed service; ISDN - caller ID & video conferencing Gigabit Ethernet in carrier & enterprise metropolitan networks

2 VPNs & Specialized Network Services continued ATM compared to IP SONET –In the backbone –In the metropolitan area –Compared to gigabit ethernet

3 virtual private networks Virtual: from the Latin excellence; Essence though not in fact actual

4 IPSec virtual private network for remote access What are the advantages of VPNs? Why are they important? How can they be made secure?

5 Key Components of Frame relay

6 Multipoint private lines with hub and spoke for small locations Why use private lines rather than a virtual private network?

7 Mesh network topology pros & cons

8 Any-to-any mesh design in a VPN; hub and spoke (star) to headquarters for Internet access. Mesh; hub & spoke combo

9 Local and interexchange channels of a private line Billing, repair & installation ramifications

10 Integrated access device for T-1s carrying voice and data Small & medium companies Implication of competition

11 T-1 and E or Megabits per second –Bell Standard –IT Standard Applications T-1 Mux 24 or 30 channels Fiber, copper or wireless media

12 28 T-1s = a T-3 Circuit ISP Internet London Dallas T-3 T-1 Boston Fiber or Wireless

13 Videoconferencing using three bonded BRI ISDN circuits

14 BRI ISDN bonding

15 PRI ISDN carrying the caller’s billed telephone number automatic number identification (ANI). The ANI is often the same as the customer’s telephone number. Primary rate interface ISDN

16 DSLAMs in digital loop carriers (remote terminals)

17 Digital subscriber line service No need for fiber to the home or business A response to cable providers Use of same copper already deployed Strategic implications of RBOC & cable offerings downstream voice data upstream

18 DSLAM connection to an Internet service provider

19 Figure 5.14 Neighborhood mini remote access multiplexers (MiniRAMs).

20 Gigabit Ethernet fiber-optic cabling and metropolitan fiber rings

21 Leasing wavelengths in the metropolitan area

22 Parallel streams in an ATM circuit Fixed size cells Quality of service Asynchronous switching In the frame relay backbone

23 - bidirectional duplicate rings in a carrier’s backbone network - The fiber glut & pricing - SONET in the enterprise SONET rings in the backbone

24 Summary What are the major trends in high-speed networking Why are carriers, residential consumers and enterprises demanding higher-speed services Which technologies will supply the required capacity and speeds? Contrast & compare: ISDN, T-1, T-3, Gig-E, SONET & ATM