Network Intrusion Detection

8 bits

255

Hardware Address that is assigned to a Network Card

Resolves a known MAC address with its corresponding IP address

53

TCP Acknowledgement is sent back from the receiver

TCP is more reliable, but slower and requires more overhead than UDP

Communicating Errors

RESET

Client to Server: SYN set Server to Client: SYN/ACK Client to Server: ACK

An embedded protocol of TCP follows the IP header

When there are more bytes in the packet than the size of the Maximum Transmission Unit

IP identification field More Fragment bit Fragment offset

When the TTL value becomes 0 the packet is expired

To make sure the IP header data wasn't corrupted in transit

To resolve a hostname to an IP address

Responds with a ICMP port unreachable message to the sender

Responds with a RESET flag since it didn't sent the SYN in the first place

IPv6 addresses are 4 times longer Some fields/functionality previously in IPv4 header are now in IPv6 extension headers

1st: Ethernet header 2nd: IP header 3rd: ICMP header 4th: optional ICMP data

Moves an IP packet one hop closer to its destination

The Embedded Protocol of the packet

Gives an order to each packet so they can be recompiled by the receiver

Issue an ARP request to discover MAC address associated with the IP address

Decrements TTL value by 1 Recalculates IP checksum

Result of router breaking up packets that are too large according to frame size limitation

Number of segments that can be sent before an acknowledgement must be received

58

You replace additional 0's with a : symbol e.g. 1080::8:800:200C:417A

IP address combined with a Port number

They replicate

1st: Discover 2nd: Offer 3rd: Request 4th: Acknowledgement (DORA)