TCP/IP basics Flashcards
What OSI level does TCP work on?
Level 4
What level does Internet protocol work on?
Level 3
What are five things you will find in a TCP packet
Addressing Time to live Total length Protocol (tcp or udp) Ver: ipv4 or 6
With which protocol is “Syn, Syn Ack, Ack” associated?
Tcp has the three way handshake
What is the unabbreviated term for UDP
User datagram protocol
True or false: UDP does not get chopped up during the transport layer and simply gets a header slapped on it
True
What is a packet’s checksum?
A method of verifying the data’s integrity by comparing the checksum to the final product
What two protocols use UDP
DNS, DHCP
What is the method used by NICs to find the mac address of a computer it wishes to communicate with?
It will check its subnet to see if the computer is on the same network, and then send out an address resolution protocol broadcast.
What is the cmd command to see the mac addresses and IPs your computer is aware of on your LAN?
arp -a
How does your computer know where to send a packet when it’s not on the LAN
It sends it to the default gateway by default
How do you figure out the amount of hosts by looking at the IP.
2 to the power of (host bits)
2 represents the binary on/off state
What is the kool kid pattern for remembering ip classes
68123
What is the class a range
1-126
What is the class b subnet range
128-191
What is the class C subnet range
192-223
What is the 8 times table multiples pattern
8 16 24 32 40
48 56 64 72 80
What are the private IP address classes?
A - 10 - 10.255.255.255
B - 172.16.0.0 - 172.255.255
C - 192.168.0.0-192.168.255.255
What is the process for finding a network ID for 192.168.32.56 /23
1) Write down the IP and Subnet in binary, though only the octet in which the networkID becomes the host ID (In this case, octet 2)
2) Compare the binary and if both the IP and Subnet have a 1, turn the binary into its integer number, like so:
Subnet: 1 1 1 1 1 1 1 0
IP: 0 0 1 0 0 0 0 0
^
There are matching 1’s in this line. So convert it to 32.
Your network ID is 192.168.32.0 As anything after the 32 binary number is a host bit, you can ignore the 56 on the end of the IP.
____________________________
3) Take away the network ID binary and use the rest to determine the host range:
Subnet is 1 1 1 1 1 1 1 0 equaling 254. This means you have 1 host bit for this octet, plus the eight from the following octet. 2 to the power of 9 is 512 hosts. (-2)
- 168.32.0 to 192.168.33.254 host range with all host bits on the lower range being off and all the host bits of the higher range being on.
http: //www.network-calculator.com/ use this for practice
What is the four way DHCP handshake?
DORA Discover Offer Request Ack
What are three things a DHCP server needs to function
IP scope
Gateway info
Subnet
True or false: Switches block broadcasts
False. Routers block broadcasts.
What is DHCP relay?
DHCP relay enables routers to accept the DHCP discoveries of hosts on their network and forward it to a DHCP server elsewhere in the building.
Using a mac address as an identifier to identify a specific computer, a DHCP server can do what?
Make sure the one computer always gets the same address.
What is failover dhcp?
Having a backup dhcp server in the even to of a failure. uses same scope as primary server.
What is rogue dhcp?
Someone else, innocent or not, plugging a dhcp server into your network. You can tell if a pc is on a bad network by looking at the gateway information in ip config.
