Optical Networks - _Problems9_123

B how do you know that your solution uses the minimum

Info icon This preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
(b) How do you know that your solution uses the minimum possible number of wavelengths required to do this routing for any algorithm?
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
620 WDM Network Design (c) How many ADMs are required at each node to support this traffic? (d) How many ADMs are required at each node if instead of fixed-wavelength routing, you decided to use point-to-point WDM links and receive and re- transmit all the wavelengths at each node? How many ADMs does wave- length routing eliminate? 10.3 Derive (10.1). What is the value when N is odd? 10.4 Derive (10.5). What is the value when N is odd? 10.5 Derive (10.8) for the case where there is one full-duplex lightpath between each pair of nodes. Hint: Use induction. Start with two nodes on the ring, and determine the number of wavelengths required. Add two more nodes so that they are diametrically opposite to each other on the ring and continue. 10.6 Show that when N is odd, (10.8) is modified to W = t N 1 N 2 1 8 . 10.7 Derive (10.9). What is the value when N is odd? 10.8 Develop other network designs besides the ones shown in Examples 10.2, 10.3, and 10.4, and compare the number of LTs and wavelengths required for these designs against these three examples. 10.9 Consider the LTD problem in Section 10.2.1 but with the following changes: There is a cost c i,j to set up a bidirectional lightpath between nodes i and j . The cost includes the cost of the transponders that terminate the lightpaths and any intermediate transponders and amplifiers. λ s,t is bidirectional traffic rate between source-destination pairs (s, t) . The bandwidth of a lightpath is r . The objective is now to minimize the total cost of the network. Give the MILP formulation for this LTD problem. 10.10 This problem illustrates the complexity of wavelength assignment in networks where the transmission is bidirectional over each fiber. Consider the two networks shown in Figure 10.21. In Figure 10.21(a), the network uses two fibers on each link, with two wavelengths and unidirectional transmission on each fiber. In Figure 10.21(b), the network uses one fiber on each link, with four wavelengths. Transmission is bidirec- tional on each fiber, with two wavelengths in one direction and two in the other. No wavelength conversion is allowed in either network. Both networks have the same nominal capacity (four wavelengths/link). Which network utilizes the capacity more efficiently?
Image of page 2
Problems 621 (a) (b) λ 1 λ 2 λ 1 λ
Image of page 3

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern