Network+ Chapter 8 Flashcards
What is subnetting? Ch 8 pg234
to take one larger network and break it into a bunch of smaller networks.
How do you create a subnet? Ch 8 pg 234
you take bits from the host portion of the IP address and reserve them to define the subnet address. This means fewer bits for hosts, so the more subnets, the fewer bits are left available for defining hosts.
A____________ is a 32-bit value that allows the recipient of IP packets to distinguish the network ID portion of the IP address from the host ID portion of the IP address. Ch 8 pg 236
subnet mask
What is the CIDR Value of 255.224.0.0 ?
/11
What are the valid hosts?
Ch 8 pg 236
Valid hosts are the numbers between the subnets, omitting all the 0s and all the 1s.
What are the valid subnets?
Ch 8 pg 236
2x = number of subnets. x is the number of masked bits, or the 1s. For example, in 11000000, the number of 1s gives us 22 subnets. In this example, there are 4 subnets.
.
The slash notation_ means how many bits are turned on (1s). pg 237 ch 8
(/)
If you ping the loopback address and receive an “unable to contact IP driver, error code 2” message, you need to do what?
Ch 8 pg 257
reinstall the TCP/ IP protocol suite on the host.
It’s basically the method that Internet service providers (ISPs) use to allocate a number of addresses to a company or a home connection.
ch 8 pg 237
Classless Inter-Domain Routing (CIDR).
Displays IP-to-MAC-address mappings on a Windows PC
ch 9 pg 259.
arp -a.
Uses an Internet Control Message Protocol (ICMP) echo request and replies to test if a host IP stack is initialized and alive on the network.
Ping
What is the acronym of ping? Ch 8 pg 259
Packet InterNet Groper
1) Sally’s is complaining that she can’t communicate to a server that just happens to be on a remote network: What is the 1st step in trouble shooting this problem?
Ch 8 pg 257
Open a command prompt window on Sally’s host, and ping 127.0.0.1
if this ping is successful what should you see on your screen?
Ch 8 pg 257
Reply from 127.0.0.1: bytes = 32 time
If it fails what will you need to do to correct this issue?
Ch 8 pg 257
If it fails, then you have an IP stack failure and need to reinstall TCP/ IP on the host.
(2nd Step)
Ping the IP address of the local host.
C:\ > ping 172.16.10.2
If that’s successful, your_______is functioning. If it fails, there is a problem with the ______.
Ch 8 pg 258
Network Interface Card (NIC)
(3rd step)
From the command prompt window, ping the default gateway (router). C:\ > ping 172.16.10.1
If the ping works what should that tell you?
Ch 8 pg 258
If the ping works, it means that the NIC is plugged into the network and can communicate on the local network. If it fails, you have a local physical network problem that could be anywhere from the NIC to the router.
If steps 1 through 3 were successful,what should you ping next?
Ch 8 pg 258
remote server.
If that works, then you know that you have IP communication between the local host and the remote server. You also know that the remote physical network is working.
Here’s a list of situations when it’s best to have NAT on your side:
Ch 8 pg 264
You need to connect to the Internet and your hosts don’t have globally unique IP addresses.
You change to a new ISP that requires you to renumber your network.
You need to merge two intranets with duplicate addresses.
This type of NAT is designed to allow one-to-one mapping between local and global addresses. Keep in mind that the static version requires you to have one real Internet IP address for every host on your network.
Ch 8 pg 265-266
Static NAT (SNAT)
This version gives you the ability to map an unregistered IP address to a registered IP address from a pool of registered IP addresses. You don’t have to statically configure your router to map an inside-to-an-outside-address as you would using static NAT, but you do have to have enough real, bona-fide IP addresses for everyone who’s going to be sending packets to and receiving them from the Internet.
Ch 8 pg 265-266
Dynamic NAT (DNAT)
This is the most popular type of NAT configuration.
Ch 8 pg 265-266
Overloading
Name of the inside source address before translation
Ch 8 pg 266
Inside local
Name of the destination host before translation
Ch 8 pg 266
Outside local
Name of the inside host after translation
Ch 8 pg 266
Inside global
Name of the outside destination host after translation
Ch 8 pg 266
Outside global
