Q1.

a) In an IPv4 packet, the value of HLEN is (1010)₂ , and the value of the total length field is (005A)₁₆. How many bytes of data are being carried by this packet?

b) A packet has arrived in which the offset value is 175, the value of HLEN is 10, and the value of the total length field is 100. What are the numbers of the first byte and the last byte?

Q 4. See the network shown below. The figure consists of four automatous systems (ASs) each running RIP as an internal routing protocol. Moreover, iBGP and eBGP are used as border gateway protocols. AS4 is connected to an external network called x. By carefully examining the figure below, answer the following questions:

Which protocol is used to tell router 1b about network x? iBGP, eBGP, RIP or OSPF?

Which protocol is used to tell router 2b about network x?

Which protocol is used to tell router 3b about network x?

Which protocol is used to tell router 1c about network x?

4b 4c AS4 3c 2c 3a 2a 2b 3b 1c 1b AS2 AS3 1d ASI