Q10: Complete the frames (x & y) given below with appropriate port, IP and MAC addresses. The sender Host E has two applications running; one for email with port number 49254 and the other for accessing the web server with port number 52167. The frame x is intended for the BRACU Web server and frame y is coming from the Email Server. (MAC addresses are alphabets and IP addresses are numbers) [5] Port 80 Frame y К 93 BRACU G/51 Router BRACU Web ISP Frame x Server Router I/91 Port 25 H/52 F/25 Hub-PT Hubo A/20 Svitc -PT Switho Swich-P sitchi Enail Server J/92 B/21 E/24 C/22 D/23 Sender Frame X D. Mac S. MAC D. IP S. IP D. Port S. Port Data Trailer Frame Y D. Mac S. MAC D. IP S. IP D. Port S. Port Data Trailer

Match the packets to the correct sequence of actions *PSH,ACK *SYN *RIN,RST *ACK,SYN *FIN *RST *ACK   1. server responds = 2. client requests connection to the server = 3. client responds =

SMTP (Simple Mail Transfer Protocol) is the standard protocol for transferring mail between hosts. A TCP connection is set up between a user agent and a server program. The server listens on TCP port 25 for incoming connection requests. The user end of the connection is on a TCP port number above 1023. You have defined the packet filter rule set shown in the table below. These rules permit and/or deny inbound and outbound traffic between the user agent and the mail server. Describe the purpose of each packet filter rule in the table.  Rule Direction Source Address Destination Address Protocol Destination Port Action A2 In External Internal TCP 25 Permit B2 Out Internal External TCP > 1023 Permit C2 Out Internal External TCP 25 Permit D2 In External Internal TCP > 1023 Permit E2 Either Any Any Any Any Deny

If a host has received the following segments in TCP:[1, 1000], [4001, 5000], [5001, 6000], [1, 1000]. (1)Show the contents of SACK option to be sent.