| A | B |
|---|
| encapsulation | when data is moved down the OSI model and a new header and footer are added |
| OSI Model | 7 layer model of TCP/IP |
| Network layer | routing and switching creates virtual circuits between computers |
| header | section of datagram that shows size of packet |
| fragmentation | allows IP datagram to be broken into smaller datagrams for transport |
| FIN Packet | used to terminate a handshake |
| SYN packet | used to initiate 3 way handshake |
| SYN / ACK packet | used to initiate 2nd step in response to SYN packet |
| EMI | intercepting electromagnetic signals (fiber most resistent to this) |
| FCS o CRC(cyclic redundency check) | provides bit level integrity check of packet |
| socket | combination of port number and IP address |
| DoS (Denial of Service Attack) | Syn flood |
| Soofing | computer impersonates another computer |
| man-in-the middle | hacker palces himself between source and destination computers |
| ARP cache poisoning | incorrect or spoofed MAC addresses added |
| Session hijacking | disables ability of a computer to communicate during then imitates that computer |
| port scanner | looks for open ports |
| payload | data that needs to be delivered |
| Internet header | length of header (20-60 bytes) |
| Total Length | byte measure of the datagram and includes header and payload (16 bits) |
| Identifier | assigns unique number to packet and is used to reassemble fragmented datagrams (16 bits) |
| Flags | indicates fragmentation of datagram (3 bits) |
| Fragmentation Offset | specifies where the in the IP datagram the fragment fits (13 bits) |
| Time to Live | specifies the max number of links packet can pass through to reach destination (8 bits) |
| Protocol | transport layer specification (8 bits) |
| Source IP Address | IP address of sending computer |
| Options and Padding | added information to IP header |
| ICMP message | Contains: type & code & Checksum & optional data-reports errors and control messages |
| UDP | connectionless protocol without a handshake |
