2. Consider a slotted TDM hierarchical network in which there are 8 computers sharing a10 Mbps channel to a router R1, sending packets to R1 which must all be forwarded byR1 over an outgoing link (called the MAN link), as shown in Figure 1. Computers A-Halways have packets waiting to be sent, so no timeslot on the shared LAN is idle. Ignorethe propagation delay on the LAN. The MAN link outgoing from R1 is a 100 Mbps link.The network layer protocol in use has a PDU with exactly 40 bytes of header and exactly200 bytes of payload (SDU). The DLC layer protocol in use on the LAN has a PDU withexactly 40 bytes of header and 20 bytes of trailer. The DLC layer protocol in use on theoutgoing link from R1 has a PDU with 40 bytes of header and no trailer. The physicallayer does not impose any bit overhead in either channel. Use 1 Mbps = 1000000 bps.BDEFGHR1R2Figure 1(a) What is the transmission delay of a bit for Computer A?(b) What is the transmission delay of a DLC PDU for Computer A?(c) The TDM slotting of Computers A-H is at the individual PDU level, i.e. a PDUtransmission from Computer A on the LAN is followed by one from Computer B, and soon. In the LAN, each network layer PDU is encapsulated in one DLC PDU. If theoutgoing link from R1 follows the same discipline, what is the width of a DLC PDU onthe MAN link? (The transmission time of a bit or group of bits is sometimes referred toas their "width" on the line.)(d) R forwards each packet as soon as it is completely received. Ignore processing andqueueing time at R1, if any. What is the delay between the instant when a packet firststarts transmission at Computer A and the instant when the same packet startstransmission at R1?(e) What is the amount of time between two successive PDU transmissions are seen onthe MAN link?(f) What is the bitrate perceived by the network layer of Computer A?

In this network scenario, the intricacies of a slotted Time Division Multiplexing (TDM) hierarchical…

2. Consider a slotted TDM hierarchical network in which there are 8 computers sharing a 10 Mbps channel to a router R1, sending packets to R1 which must all be forwarded by R1 over an outgoing link (called the MAN link), as shown in Figure 1. Computers A-H always have packets waiting to be sent, so no timeslot on the shared LAN is idle. Ignore the propagation delay on the LAN. The MAN link outgoing from R1 is a 100 Mbps link. The network layer protocol in use has a PDU with exactly 40 bytes of header and exactly 200 bytes of payload (SDU). The DLC layer protocol in use on the LAN has a PDU with exactly 40 bytes of header and 20 bytes of trailer. The DLC layer protocol in use on the outgoing link from R1 has a PDU with 40 bytes of header and no trailer. The physical layer does not impose any bit overhead in either channel. Use 1 Mbps = 1000000 bps.

2. Consider a slotted TDM hierarchical network in which there are 8 computers sharing a 10 Mbps channel to a router R1, sending packets to R1 which must all be forwarded by R1 over an outgoing link (called the MAN link), as shown in Figure 1. Computers A-H always have packets waiting to be sent, so no timeslot on the shared LAN is idle. Ignore the propagation delay on the LAN. The MAN link outgoing from R1 is a 100 Mbps link. The network layer protocol in use has a PDU with exactly 40 bytes of header and exactly 200 bytes of payload (SDU). The DLC layer protocol in use on the LAN has a PDU with exactly 40 bytes of header and 20 bytes of trailer. The DLC layer protocol in use on the outgoing link from R1 has a PDU with 40 bytes of header and no trailer. The physical layer does not impose any bit overhead in either channel. Use 1 Mbps = 1000000 bps.

Operations Research : Applications and Algorithms

4th Edition

ISBN:9780534380588

Author:Wayne L. Winston

Publisher:Wayne L. Winston

Chapter20: Queuing Theory

Section20.10: Exponential Queues In Series And Open Queuing Networks

Problem 8P

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