•3 Applications Places System (fe£ú 3 j.,,. • Eile Edit yiew - 0 History gookmarks Iools Help + 0 A (-11 http://www.google.cz/ ^ Nejnav5lévovaně,..v Q Chytré záložky v ^ Sprava v 1. DNS www.google.cz ??? 74.125.87.105 i, /et a Application Presentation Session Transport Browser /es\ 2. TCP connection establishment establish TCP connection Application Presentation Session Transport TCP header srcport = anyclientport dstport = 80 SEQ = 23022 SYN = 1 segment 3. Send TCP SYN packet Application Presentation Session Transport IP header sreaddress = clientIP dstaddress = 74.125.87.105 TTL = 15 datagram/packet 3. Send TCP SYN packet 3.1 Add IP header a Application Presentation Session Transport Ethernet header srcMACaddress = clientMAC dstMACaddress = ??? frame C 3. Send TCP SYN packet 3.2 Add Ethernet header ) Application Presentation Session Transport 1010110101001110011010011001010101010 3. Send TCP SYN packet 3.3 Convert to binary form ) a Application Presentation Session Transport 3. Send TCP SYN packet 3.3 Convert into signals and send 3. Send TCP SYN packet 3.4 Receive signals and convert into binary form . Ethernet header srcMACaddress = clientMAC dstMACaddress = routerlMAC r 3. Send TCP SYN packet 3.5 Decide about appropriate output port frame 3. Send TCP SYN packet 3.6 Forward the frame [3. Send TCP SYN packet 3.7 Receive signals and convert into binary form 3. Send TCP SYN packet 3.8 Receive the frame Ethernet header srcMACaddress = clientMAC rlMAC ] IP header srcaddress = = clientIP dstaddress = = 74.125.87.105 TTL = 14 3. Send TCP SYN packet 3.9 Extract the IP header and according to the routing table forward the packet; decrease TTL datagram/packet Ethernet header srcMACaddress = routerlMAC dstMACaddress = router2MAC 3. Send TCP SYN packet 3.10 Construct new frame 3. Send TCP SYN packet 3.10 Convert it into binary form and into signals and send to the network 3. Send TCP SYN packet 3.12 Receive signals and convert into binary form Application Presentation Network Dat;i li'ik 3. Send TCP SYN packet 3.13 Receive the frame Ethernet header srcMACaddress = router4MAC dstMACaddress = router5MAC ; Application Presentation 3. Send TCP SYN packet 3.14 Receive the IP packet and consult routing table; forward the packet to appropriate destination; decrease TTL cation IP header srcaddress = clientIP dstaddress = 74.125.87.105 TTL= 10 Network datagram/packet Data link Physical 3. Send TCP SYN packet 3.15 Construct new frame Application ie Presentation Ethernet header srcMACaddress = router5MAC dstMACaddress = googleMAC Network □ D frame Data link Physical 3. Send TCP SYN packet 3.15 Convert into binary form and into signals and send to the destination Application Presentation Network D.it.i li'ik 3. Send TCP SYN packet 3.16 Receive signals and convert into binary form Applies Presentation bession 1010110101001110011010011001010101010 Data Ink Physical 3. Send TCP SYN packet 3.17 Receive the frame and decide about output port Applir: Presentation Ethernet header srcMACaddress = router5MAC dstMACaddress = googleMAC frame Data Ink Physical 3. Send TCP SYN packet 3.18 Forward the frame Applies Presentation bession 1010110101001110011010011001010101010 Data Ink Physical 3. Send TCP SYN packet 3.19 Receive the signals and convert into binary form 1010110101001110011010011001010101010 3. Send TCP SYN packet 3.19 Receive the frame Ethernet header srcMACaddress = router5MAC dstMACaddress = googleMAC \ frame Application Presentation Session Iransport Data Ink 3. Send TCP SYN packet 3.20 Receive the IP packet IP header srcaddress = = clientIP dstaddress = = 74.125.87.105 TTL= 10 \ J datagram/packet 3. Send TCP SYN packet 3.21 Receive the segment TCP header srcport = anyclientport dstport = 80 SEQ = 23022 SYN = 1 segment 3. Send TCP SYN packet 3.22 Deliver the connection request to the appropriate application WWW server (apache) deliver the connection request 3. Send TCP SYN packet 3.22 Reply to the connection request WWW server (apache) accept the connecti Application 3. Send TCP SYN packet 3.23 Construct the appropriate TCP segment and SEND IT BACK TO THE NETWORK (to the client) note: srclP = 74.125.87.105, dstIP = clientIP, srcMAC = googleMAC, dstMAC = router5MAC TCP header srcport = = childsrvport dstport - - anyclientport SEQ = 7282 SYN = 1 ACK= 23064 segment ) Application Browser Presentation /-. Session j Udid / request the Transport web page Network Data link Physical 3. Finalize TCP connection establishment (receive SYN ACK and send ACK) 4. Request the appropriate webpage (defined by URL "www.google.com") Application Presentation Session Transport Data 11-ik Physical TCP header sreport = anyclientport dstport = childsrvport SEQ = 24001 4. Request the appropriate webpage (defined by URL "www.google.com") 4.1 Encapsulate the HTTP request and create the TCP segment data segment Application Presentation Session Transport IP header sreaddress = clientIP dstaddress = 74.125.87.105 TTL = 15 4. Request the appropriate webpage (defined by URL "www.google.com") 4.2 Construct the IP header datagram/packet Application Presentation Session Transport 4. Request the appropriate webpage (defined by URL "www.google.com") 4.3 Construct the frame Ethernet header srcMACaddress = clientMAC dstMACaddress = routerlMAC frame Application Presentation Session Transport 4. Request the appropriate webpage (defined by URL "www.google.com") 4.4 Convert into binary form ] Application Presentation Session Transport 4. Request the appropriate webpage (defined by URL "www.google.com") 4.5 Convert into signals and send 4. Request the appropriate webpage (defined by URL "www.google.com") 4.6 Receive signals and convert into binary form Ethernet heade1 srcMACaddress = clientMAC dstMACaddress = routerlMAC 4. Request the appropriate webpage (defined by URL "www.google.com") 4.5 Decide about appropriate output port frame ( 4. Request the appropriate webpage (defined by URL "www.google.com") 4.5 Forward the frame ( 4. Request the appropriate webpage (defined by URL "www.google.com") 4.6 Receive signals and convert into binary form 4. Request the appropriate webpage (defined by URL "www.google.com") 4.6 Receive the frame Ethernet header srcMACaddress = clientMAC rlMAC ) IP header srcaddress = = clientIP dstaddress = = 74.125.87.105 TTL = 14 ( 4. Request the appropriate webpage (defined by URL "www.google.com") 4.7 Extract the IP header and I according to the routing table forward I the packet; decrease TTL V datagram/packet 4. Request the appropriate webpage (defined by URL "www.google.com") 4.8 Construct new frame Ethernet header srcMACaddress = routerlMAC dstMACaddress = router2MAC 4. Request the appropriate webpage (defined by URL "www.google.com") 4.9 Convert it into binary form and into signals and send to the network 4. Request the appropriate webpage (defined by URL "www.google.com") 4.10 Receive signals and convert it into binary form Application Presentation Network Data li'ik 4. Request the appropriate webpage (defined by URL "www.google.com") 4.11 Receive the frame Ethernet header srcMACaddress = router4MAC dstMACaddress = router5MAC ; Application Presentation 4. Request the appropriate webpage (defined by URL "www.google.com") 4.11 Receive the IP packet and consult routing table; forward the packet to appropriate destination; decrease TTL ■ cation IP header srcaddress = clientIP dstaddress = 74.125.87.105 TTL= 10 Network datagram/packet Data link Physical 4. Request the appropriate webpage (defined by URL "www.google.com") 4.13 Construct new frame Ethernet header srcMACaddress = router5MAC dstMACaddress = googleMAC Application Presentation 4. Request the appropriate webpage (defined by URL "www.google.com") 4.14 Convert into binary form and into signals and send to the destination Application Presentation Network D.it.i li'ik ( 4. Request the appropriate webpage (defined by URL "www.google.com") 4.15 Receive signals and convert into binary form ] Applies Presentation bession 10101101O1O01110O11O10011001O1O10101O Data Ink Physical ( 4. Request the appropriate webpage (defined by URL "www.google.com") 4.16 Receive the frame and decide about output port Applir: Presentation Ethernet header srcMACaddress = router5MAC dstMACaddress = googleMAC frame Data Ink Physical ( 4. Request the appropriate webpage (defined by URL "www.google.com") 4.17 Forward the frame Applies Presentation bession 1010110101001110011010011001010101010 Data Ink Physical 4. Request the appropriate webpage (defined by URL "www.google.com") 4.18 Receive the signals and convert into binary form 1010110101001110011010011001010101010 4. Request the appropriate webpage (defined by URL "www.google.com") 4.18 Receive the frame Ethernet header srcMACaddress = router5MAC dstMACaddress = googleMAC \ frame Application Presentation Session Iransport Data Ink 4. Request the appropriate webpage (defined by URL "www.google.com") 4.18 Receive the IP packet IP header srcaddress = = clientIP dstaddress = = 74.125.87.105 TTL= 10 \ datagram/packet 3 ( 4. Request the appropriate webpage (defined by URL "www.google.com") 4.18 Receive the TCP segment TCP header srcport = anyclientport dstport = 80 SEQ = 23022 segment 4. Request the appropriate webpage (defined by URL "www.google.com") 4.19 Deliver the web page request WWW server (apache) 4. Request the appropriate webpage (defined by URL "www.google.com") 4.19 Construct the reply and send it BACK TO THE CLIENT (if necessary, fragment the packets) WWW server (apache) Application construct th reply web page 4. Request the appropriate webpage (defined by URL "www.google.com") 4.19 Construct the appropriate TCP segment(s) (if necessary, fragment the packets) and SEND IT BACK TO THE CLIENT TCP header TCP header srcport = childsrvport 1 srcport = childsrvport dstport = anyclientport dstport = anyclientport SEQ = 13675 SEQ =12345 ] data2 I I ] datal segment.2 segmentl 3