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Internet TechnologyNETW 902Tutorial 1

Mohamed Esam

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Main Points for Problems 1. ALOHA2. Slotted ALOHA3. CSMA/CD4. Token Ring, Token BUS & Ring Types. (last Tutorial)5. BUS Segments6. WLAN7. FDDI8. Spanning Tree9. Performance of (Aloha, CSMA & Token Ring)

10. SONET11. ATM12. Virtual Connections13. ISDN14. Dial up15. DSL

Ch’s 1&2Till page: 200

Ch’s 3Till page: 255

Ex.1:LAN-Inter working& Spanning TreeEx.2:MAC protocols Performance

Ex.3:IP Addressing, ATM& Access Networks

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16.Internet Arch. & IP Addressing.17.ARP18.MTU19.Routing Functions20.Forwarding21.Routing Principles22.Distance Vector Algor.23.Link State Algor.24.Path Vector Algor.25.Routing in Internet.26.Internet Routing Protocols27.ARQ28.UDP29.TCP30.QoS

Some of Ch’s 4&5Till page: 554

Ex.4:Distance Vector &Link State Routing

Ex.5:TCP

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Hints

• The final exam is maximum 2 hours.• To solve the theoretical part, you

have to read the whole curriculum at least one time.

• To solve problems, you have to get the idea of each technology + Tutorials.

• Check Solved Exams after 2005.• For any questions, send to

mohamed.esameldin@guc.edu.eg

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Exercise 1

Part 1 Check Exercise Solution

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Bridge Learning (Part2)

• The Bridge its self can determine the port of each station

BridgeSource:3 Dest: 5

•If St.5 known send to its port only•If not known send to all ports except the port of reception (1) [flooding]

•Save that St.3 in port 1

(1)

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Bridge Loop Problem

S1

B1 B3

B2S21

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1 2

2

FS1(1)

F

S1(2)?

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Spanning Tree• Root Bridge:

– bridge with the lowest bridge ID• Root Ports:

– The other bridges ports with the least cost path to the root bridge. If the same, select the minimum port number.

• Designated Bridge:– For each LAN, it’s the bridge that offers minimum cost to

the root bridge. If the same, select the minimum bridge ID.

• Blocked Port:– Neither Root nor Designated, the link that causes looping

• For no looping, remove links that are not with Root or Destined ports

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Part2-Q5

• Dashed link and the corresponding bridge ports are not there. They will be added later.

• Station A sends an Ethernet frame destined to station D.• Describe how the frame is transmitted through the network. • For each traversed bridge describe the actions performed by the

bridge upon reception of the frame. Sketch the forwarding data bases of all four bridges.

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1 B2 1 A 1 No floods 2,3

2 B1 2 A 2 No floods 1,3

3 B3 2 A 2 No floods 1,3

4 B4 2 A 2 No floods 1,3

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Q6

a

b

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Q7

Apply Spanning Tree

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Q7 (Cost is No. of LAN’s)

B2 B3

B4B1

(1)

(2)(1)

(4)

(3)

(2)

(1)

(3)

(2)

(3) (1)

(2)(3)

(4)Root Bridge

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Message Format: (Bridge, Root ID, Path cost)

Root bridge 1 is < 2

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• Assuming B4 has received from B1 before B3

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Port

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Steady state of Q7

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Q8 Since B3 receives:Same root ID “2nd element =1”Same cost “3rd element =1”Minimum Port ID is selected Next Slide Figure

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Q8

(1)

(2)Port 2 >1

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Q9

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IKR-Simlib

1. Connect to the Internet2. Install Ubuntu: https://help.ubuntu.com/8.04/installation-

guide/i386/ch05s01.html#id28366323. Open Shell and install g++ compiler by ( # sudo apt-get

install build-essential ) and check that the g++ package is included.

4. Unzip SimLib folder5. install your simlib from the original tar-ball     #

./configure –prefix=/IKRTools/IKRSimLib-2.6.46. sudo apt-get install autoconf     # make7. inside mohamed2/IKRSimLib     # sudo make install8. # sudo apt-get install grace (to get xmgrace)9. open new shell10. go to the model build folder, then # make