Hands-On Design Process

1. Hands-On Design Process for Data Networks 1. Model only 9600 BPS lines for ALs since 56000 BPS lines are too costly for the traffic loads considered 2. Model 1, 2, & 3 Optimally-Located SWs for both MD and Star Topologies

2. DATA NETWORKS: The Design Process • Prepare aVHD file using the CPE data • Prepare a NLT file for useful link types • Select the valid tariffs in a TARIFF file • Prepare a valid LINK file if required • Use “Find COGs ”capability for choosing Nsw SW locations for preparing a valid SWF ( Fix NDEC & DECT in SDF for COGs ) • Adjust the required SDF parameters

3. SDF - The Data-Related Design Parameters • ATP ( Tr analysis type), Wm, ALT, TKLT • UPR,HPR,HTT, R , T , T , K mph np hm pg • IML, RML, BLKL, ICPB ( Inf. bytes ./block) • N (no. of nodes allowed/ VMPT; valid for only Doelz networks), MTKU, TGF cu • F =0 or 1 (for use of Sharma’s exchange opt algorithm for additional optimization)

4. Parameters ATP, Wm :Values Allowed • ATP =1 implies an async protocol ( ) e.g. Burrough , Frame relay, FPS, ATM • ATP =2 implies an Doelz’s VMPT & FPS ( for superimposed BSC netlinks ) • ATP=3 implies SNA BSC protocol ( ) e.g. polling of N controllers on a netlink ATP=4 implies an X.25 protocol • Wm must be < link-capacity per NLT •

5. Parametrs UPR, HPR, HTT, Tnp, Thp,Tpg 1. UPR, HPR are SL rates usually less the AL C. 2. HTT (host think time): generally about 1-10 sec. 3. Rmph applies to Doelz Networks; Ignored here 4. Tnp (nodal processing time): switch time/msg. 5. Thm (half modem time): generally < 5 ms. 6. Tpg (propagation delay time): about .01 sec/mi

6. Params:IML, RML, BLKL, ICPB, MTKU 1. IML (inp. msg. length in bytes) : Protocol dependent 2. RML (response msg. Length in bytes): same as above 3. BLKL (block length): packet or cell size in bytes 4. ICPB (information bytes per block/packet/cell) 5. MKTU (max. trunk utilization): It must be less than unity (or 1) since it determines the available data rate on the trunks.

7. Design Parameters (Contd) • Flk =0: StarData Networks with with one ALT-type as defined by ALT of SDF • Flk =1: StarData Networks designed with an hierarchy of concentrators as determined by the LINK-file entries. • Flk =1 and FVC0=1 yields a 2-level Star- Data Network with a mix of AL-types as defined by the LINK file connecting all the CPEs

8. Design Parameters (Contd) • Flk =0: DLNets and MDNets are designed with one AL-Type=ALT • Flk =1: DLNets and MDNets are designed with an hierarchy of concentrators/ ALs as determined by the LINK file entries • MSTNets are always designed with a single AL type=ALT & Wm =Infinity

9. Data Network Design Process 1. Open/View the input file “Files” and enter VHD17, LINK17, MAPusa , TARIFF, SDF, NAME17, LATA17 and SWF in the proper cells and UPDATE. 2. Open/View the input file “SDF” and update values of ALT=1, TKLT=1, for leased 9600 BPS lines, ATP=3 for BSC protocol, Wm = 6300 bps & BBTF=2.

10. 3. Also use UPR/HPR=9600bps, IML=28, RML=300 bytes, Tnp=10 ms, Thm=4 ms, Tpg= .01 ms/mi, TGF=1, Flk=0, Fflt=0 4. Use SWF with 1 SW at 1, 2 SWs at 1 and 11, 3 SWs at 1, 11 and 2 to create three DataNets with MD topology . 5. Repeat Steps#4 to model DataNets based on Star topology. 6. Tabulate results with REMARKS.

11. 7. Choose the optimum network topology based on your criteria (cost or response time) 8. For the optimum DataNet selected, plot total costs and Tr (response time) in the range 500 <Wm <9500 bps. Wm is defined in the NLT input file, for each link type. Plot the results. Make some cogent observations.

12. DataNet Assignments 1. Add to the MSWord document a Result- Tabulation of 6 DataNets with your own original remarks. 2. Include a DBF for the Optimum DataNet 3. Include the tabulation of Total Monthly Costs and Tr for Optimum DataNet Versus Wm with observations about the optimum DataNet