Network Protocols Flashcards
Convert to Binary Octet = 234
11101010
Convert to Binary Octet = 168
10101000
Convert to Binary Octet = 99
01100011
Convert to Binary Octet = 25
00011001
Convert to Binary Octet = 189
10111101
Convert to Digital = 01010101
85
Convert to Digital = 10011111
159
Convert to Digital = 00111001
57
Convert to Digital = 10011100
156
Convert to Digital = 11011001
217
How does the network ID in an IP address relate to the host ID?
The network ID on the left identifies the subnet the host belongs to, and the host ID on the right identifies its place on that subnet. Each can vary in length, but the two together are always 32 bits.
How can classful addresses be used in a classless address system?
CIDR is backwards-compatible. Existing class A, B, and C addresses just have subnet prefixes of /8, /16, and /24 respectively.
What can you tell about this address: 10.124.1.92
It’s a private network address, routable within an organization but not on the Internet.
What can you tell about this address: 127.0.0.1
It’s a loopback address: packets sent there just return to the local host.
What can you tell about this address: 169.254.1.13
It’s a self-assigned address, which works on the local segment but can’t be routed.
What can you tell about this subnet mask: 255.0.255.0
It’s not a valid subnet mask since it doesn’t have contiguous 1s followed by contiguous 0s. The host is improperly configured.
Loopback IPv6
::1/128 returns to the same interface. Equivalent to 127.0.0.1/8 in IPv4.
Link-local IPv6
Usable on the local segment, but not routable.
Unique local IPv6
Routable within a private network, such as one managed by a single organization or group of organizations, but not on the public internet.
Global IPv6
Routable on public networks such as the Internet
Why is IPv6 being adopted?
The most pressing reason is the depletion of available IPv4 addresses, but it also makes network configuration easier, routing more efficient, and security stronger.
What address scopes can an IPv6 unicast address have?
From smallest to largest: loopback, link-local, unique local, and global.
What IPv6 address would take the place of 127.0.0.1?
::1/128 is the IPv6 loopback address.
What can you tell about this IPv6 address: fe80::c2ad:5783:91:12c2
It’s a link-local address, self-assigned and only usable on the local network segment.
What can you tell about this IPv6 address: fd00:34a0:90d::3001:a0a7
It’s a unique-local address, routable within the organization but not on the internet.
What can you tell about this IPv6 address: 2001:d18:c34d:0:0:0:0:300
It’s a public unicast address, routable on the internet.
Your company has two sites, each with its own LAN: both are IPv6 ready, but the WAN link between the two is still IPv4. How can you reach other company servers?
You can use IPv6 addresses for hosts on your own LAN. To contact the other site you’ll need an IPv4 address unless there’s a tunneling setup.
Top-Level Domain (TLD)
The root category of the domain. Originally these were either three-letter functional categories like .com or .edu, or two letter country codes like .uk or .jp.
Domain
Represents a particular organization. Domain names are registered, or rented, from a registrar: each TLD registrar can set its own fees and eligibility requirements.
Subdomain
An optional level used for categories within the organization. The organization can allocate and use subdomains as it sees fit.
Hostname
he name of the specific host within the organization, or its alias.
Local host mocha wants to send a packet to remote host kona on its subnet. It knows kona’s address is 192.168.100.20. Describe the address resolution process mocha needs to follow.
mocha first will look in its ARP cache to see if it has kona’s MAC address. If not, it will use an ARP request using kona’s IP address to find its MAC address. Afterward, both hosts add each other to their ARP caches.
What does each segment of the FQDN mocha.corporate.javatucana.coffee represents, and who assigned it?
mocha is the host name, and corporate a subdomain: both can be assigned internally by the company. javatucana is a domain name, and was registered with and aapproved by a public domain registry. .coffee is a top level domain, which was approved by the IANA.
You want to connect to mocha.corporate.javatucana.coffee over the Internet. Describe the address resolution process your computer needs to follow
Your computer will first look for mocha’s IP address in its DNS cache. Assuming it isn’t, it will send a DNS request to its DNS server. The server will check its own address records, and consult higher level servers if necessary. Finally, it will send mocha’s IP address to your computer, which will make the connection using the default route. Finally, your computer will add mocha to its DNS cache.
Static Assignment
Manual assignment of address settings on the host itself
Dynamic Assignment
Automatic assignment of an address by a server on the local network.
Stateless Address Configuration
A private IP address chosen by the host itself through communication on its local subnet. This method produces private, non-routable addresses, so it’s only useful for local communications.
APIPA
Automatic Private IP Addressing
ARP
Address Resolution Protocol
NDP
Neighbour Discovery Protocol
CIDR
Classless Interdomain Routing
RIR
Regional Internet Registry
IANA
Internet Assigned Numbers Authority
What are the 2 types of DHCP?
DHCPv4 for IPv4 and DHCPv6 for IPv6
EIGRP
Enhanced Interior Gateway Routing Protocol
OSPF
Open Shortest Path First
RIP version 2
Routing Information Protocol Version 2
What are the Private Address ranges?
10.0.0.0 - 10.255.255.255 172.16.0.0-172.31.255.255 192.168.0.0-192.168.255.255
IP range for Class A private address?
10.0.0.0-10.255.255.255
IP range for Class B private address?
172.16.0.0-172.31.255.255
IP range for Class C private address?
192.168.0.0-192.168.255.255
If windows cannot obtain an IP address, it will automatically assign one. How does the beginning of this IP address always start?
169.254
How does a link-local address start on IPv6?
fe80
What problems might you see if a host was configured to use DHCP on a network without a valid DHCP server?
An APIPA or link-local address, and an inability to communicate with hosts outside the local network segment.
What problems might you see from an invalid or duplicate IP address?
Inability to reach any hosts, or unpredictable connectivity.
What problems might you see from invalid DNS settings?
Inability to reach hosts by name, even when they’re reachable by IP address.
Can you assign a static IP address while relying on an automatic DNS server assignment?
Not for IPv4; you will need to assign a DNS server manually too. IPv6 allows automatic DNS discovery without DHCP, but only if a local router is providing DNS advertisements.