Ch. 4.1 Flashcards
What does a IP header have?
Fields to manage logical addressing and forwarding functions
What does the IP do?
Provides ways to address networks and forward frames
What does the Length field indicate?
The size of the header and total packet size (including payload)
What is a standard Ethernet frame size?
1,500-byte MTU’s
What does the Protocol field indicate?
The type of data in the payload
What are common values in the IP Protocol type?
TCP/6
UDP/17
What is the hex form of UDP6?
What is the hex form of TCP 17?
0x06
0x11
What does ICMP/1?
What is it used for?
Internet Control Message Protocol
Used for status messaging and connectivity testing
What does IGMP/2?
What is it used for?
Internet Group Messaging Protocol
Used for multicasting
What does GRE/47 stand for?
What is it used for?
Generic Routing Encapsulation
Used to tunnel packets across an intermediate network. (Like VPN)
What does ESP/50 stand for?
What does AH/51 stand for?
What are they used for?
Encapsulating Security Payload
Authentication Header.
Both used for encrypted form of IP (IPsec)
What does EIGRP/88 stand for?
What does OSPF/89 stand for?
What are they used for?
Enhanced Interior Gateway Routing Protocol
Open Shortest Path First
Used by Routers to get info on paths to remote networks
What is forwarding at Layer 2 called?
What is forwarding at Layer 3 called?
Switching
Routing
What does ARP stand for?
What does ARP do?
Address Resolution Protocol
Resolves IP addressing to hardware MAC address
Layer 2 and 3 forwarding
What’s the difference between
Unicast
Broadcast
Multicast
Anycast
Unicast: 1 host to 1 host
Broadcast: 1 host to everyone in the broadcast domain
Multicast: 1 host to multiple hosts wanting originating host’s content
Anycast: 1 host to closest host of a group of same IP addresses
What does IGMP stand for?
What is it used for?
Internet Group Management Protocol
Configures group members and IP addresses
How does multicasting work? (2)
Destination IP address can have a range
Multiple hosts wanting one host’s content
What will a switch do if it’s not capable of IGMP snooping?
Treat the multicast as a broadcast and flood all the ports
What is the prefix used by multicasts?
01-00-53
How does Anycast work?
Group of hosts configured with same IP address
Signal goes to closest host
What IPv4 range is reserved for multicasting?
224.0.0.0 —- 239.255.255.255
What’s the difference between
Unicast and Multicast?
Unicast: 1 host to 1 host
Multicast: 1 host to multiple hosts wanting originating host’s content
What’s the difference between
Broadcast and Anycast?
Broadcast: 1 host to everyone in the broadcast domain
Anycast: 1 host to closest host of a group of same IP addresses
What’s the difference between
Unicast and Anycast?
Unicast: 1 host to 1 host
Anycast: 1 host to closest host of a group of same IP addresses
