Networks Review Sheet #1 - Terms (p1--34): hosts, end systems, communication links, transmission rate, packets, routers, switches, ISPs, customers, providers, Points of Presence, protocols, API, clients, server, dial-up, DSL, cable, Fiber, WiFi, physical media, twisted-pair copper wire, coaxial cable, fiber optics, radio (terrestrial or satellite), trace route (p43), IP spoofing( p60) - Terms/Malware (p57--58) malware, botnet, self-replicating, Virus, Worm, Trojan Horse - Terms/Attacks (p58-61) Denial of Service, Vulnerability Attack, Bandwidth Flooding, Connection Flooding, IP spoofing, man-in-middle attacks - (p37) Delays, Nodal Processing, Queuing, Transmission, Propagation, Total Nodal Delay, Toll Booth Analogy - (p42) Dropped packets, packet loss - (p51--53) Protocol Layering - Internet Protocol Stack - Application - messages - Transport (TCP/UDP) - segments - Network (IP) - datagrams - Link (ethernet/PPP) - frames - Physical (see above) - Each layer adds its own header - Application Layer - (85--87) client-server, examples, advantages, disadvantages - (88-89) P2P - examples, advantages, disadvantages - (p90--91) download vs upload, sockets - (p92-93) Developer uses an API, chooses transport protocol and some other parameters, with reliability, throughput, timing and security in mind - (p94--96) TCP (connection-oriented, reliable, handshake, congestion control) vs UDP (connection-less, light-weight, no guarantees) - (p97) examples of TCP, UDP applications - (p98) IP addresses - (p98) Application-layer protocols - (p103-104) Persistent vs non-persistent connections - (p113-117) Proxy server, web cache, latency measures - (p124-129) SMTP, POP3, IMAP - (p126) push vs pull protocols - (p132-143) DNS, hostname, UDP 53, centralized vs. distributed, local DNS servers, Resource Records, format of DNS request and reply - Socket programming in C (homework and see shared pdf) - send, recv, connect, accept, listen, bind - precise syntax of the system calls isn't required, but you should know what/when they're used. Chapter 3 - Transport Layer segments, (p198) best-effort delivery service, (p202) unreliable service, reliable data transfer (p202) congestion control, sockets (202,203) multiplexing and demultiplexing (203) source port,destination port (204) port scanning (208) UDP (210) -connectionless (211) -immediate send (211) -no handshake (212) -no connection state (212) -small overhead (212) -checksum (214-215) Reliable Data Transfer -bidirectional, full-duplex (217) -ACK, NAK, ARQ (219) -ARQ : error detection, feedback, retransmission (220) -stop-and-wait protocol (221) -sequence number (222) -duplicate packets and acks (222-223) -utilization (229) -go back N (230), cumulative ack (234) -sliding window (232) -selective repeat (235) TCP -three-way handshake and shutdown (244, 264-268) -MSS, MTU (244,245) -TCP segment structure (246) -RTT estimation (estimate, deviation, timeout) (250--253) -SYN flood, SYNACK (269) -double timeout interval (258) -fast retransmit (259) -flow control, receive window (262-264) -connection management (SYN, SYNACK, three-way handshake) 264-265 -connection management - closing connections with FIN 267