Week 2: IP Control/Helper Protocols Flashcards
What are the two levels required by a router to deliver a packet?
Logical Address (IP Address) Physical (MAC Address)
What does Address Resolution Protocol (ARP) do?
Performs mappings
Confined to single hop LAN
How many bits long is the Hardware Type in an ARP Packet?
16 bits
How many bits long is the Protocol Type in an ARP Packet?
16 bits
How many bits long is the Hardware Length field in an ARP Packet?
8 bits
How many bits long is the Protocol Length field in an ARP Packet?
8 bits
How many bits long is the Operation Request/Reply field in an ARP Packet?
16 bits
An ARP Request is what?
A Broadcast
An ARP Reply is what?
A Unicast
ICMP is used in which layer for what?
Layer 3 for error reporting and making simple queries
ICMP was designed to compensate for what shortcoming?
The unreliability of the IP protocol
Does ICMP correct errors?
No, it simply report them
When is no ICMP error message generated?
ICMP error messages aren’t generated for Broadcast and Multicast packets
What protocol carries/encapsulates ICMP?
ICMP is carried by IP
What are the two types of ICMP Messages?
Error-Reporting Messages
Query Messages
What are Error-Reporting ICMP Messages?
Report problems that a router or a host (Destination) may encounter
What are Query ICMP Messages?
Get specific information from a router or another host
What are the 5 types of ICMP Error Reporting Messages?
3 - Destination Unreachable 4 - Source Quench 11 - Time Exceeded 12 - Parameter Problem 5 - Redirection
What are the 4 types of ICMP Query Messages?
8 or 0 - Echo Request or Reply
12 or 14 - Timestamp Request or Reply
17 or 18 - Address Mask Request or Reply
10 or 9 - Router Solicitation or Advertisement
What are two of the more important ICMP Error Messages?
3 - Destination Unreachable
11 - Time Exceeded
