TCP/IP Network Model Flashcards
Name four application layer protocols in the TCP/IP network model.
- HTTPS (secure web)
- SSH (secure shell)
- FTP (file transfer)
- SMTP (email delivery)
What are the two protocols used in the transport layer of the TCP/IP network model?
- TCP
- UDP
What layer of the TCP/IP network model uses IPv4 and IPv6 protocols?
Internet layer, or Network Layer
What two pieces of information form a socket?
IP address and service port.
Which layer of the TCP/IP network model provides the connection to physical media?
The Link or Media Access Layer.
What three layers of the OSI network model correspond to the Application layer of the TCP/IP model?
Application (7), Presentation (6), and Session (5).
What two layers of the OSI network model correspond to the Link layer of the TCP/IP model?
The Data Link and Physical layers.
In RHEL 7 and later, what prefixes are assignes to network interfaces for ethernet, WLAN, and WWAN?
en, wl, and ww.
In RHEL 7 and later, what characters are used to represent network interface types for onboard, PCI hotbus slot, and PCI on bus M in slot N
oN,
sN,
pM
sN
How many bits are assigned as the network prefix for Class A, Class B, and Class C networks?
Class A - 8 bits
Class B - 16 bits
Class C - 24 bits
What is CIDR?
Classless Inter-Domain Routing
The newer network addressing specification, which allows for a variable number of bits in the network prefix of an IPv4 address.
What is a network mask
A binary mask whose length indicates the number of bits assigned to the network prefix that identifies a subnet.
What two forms of expressing a network mask are used?
- CIDR notation (192.168.0.1/24)
- Four 8 bit octets (255.255.255.0)
What address within a subnet is reserved for the network address?
The lowest possible address, where the host number is all binary zeros.
What address within a subnet is reserved for the broadcast address?
The highest possible address, where the host number is all binary ones.
What address is commonly used as the gateway address of a subnet?
The first available host number, which the binary number is all zeros except for a ‘1’ in the last bit.
What are the steps to find the addresses associated with a subnet, given a host’s address and mask?
Host address - 172.16.181.23/19
Mask - 255.255.224.0
1. Find the Inverse Mask - 0.0.32.255
2. Find the Network address start numbers -
172.16.(0, 32, 64, 96, 128, 160, 192, 224).0
3. Find the Network address that the given host falls under - 172.16.160.0
4. Find the Broadcast address - 172.16.191.255
5. Find the Host address range -
172.16.160.1 to 172.16.191.254
Find the network address, broadcast address, and network host rnage for the subnet 192.168.255.57/23
Host: 192.168.255.57
Subnet Mask: 255.255.254.0
1. Inverse Mask: 0.0.1.255
1. Network addresses: 192.168.254.0, 192.168.255.0
1. Broadcast address: 192.168.255.255
1. Host address range: 192.168.255.1 to 192.168.255.254
How many bits are there in an IPv6 address?
128 bits expresses in eight groups of four hexadecimal nibbles (half bytes).
2001:0db8:0000:0010:0000:0000:0000:0001
What are the rules for simplifying an IPv6 address?
- Remove all leading zeros from groups.
- Replace one or more conecutive groups of zeros with a double colon (
::) - When including a port number with an IPv6 address always wrap the IP address portion in
[]to avoid the port being confused with the address. (i.e.[2001:db8:0:10::1]:80
What does Red Hat recomend as tips for simplifying consistantly readable IPv6 addresses?
- Supress leading zeros in a group.
- Use a two-colon (
::) block to shorten the address as much as possible. - If an address contains two seperate sections of two or more groups with all zeros, reduce the leftmost section to
::and the rightmost section to:0:for each group. (i.e. shorten2001:0000:0000:0000:0db8:0000:0000:0000to2001::0db8:0:0:0 - Although it is allowed, do not use
::to shorten a single group of zeros (:0000:). Use:0:instead and leave::for multiple groups of all zeros. - Always use lowercase letters for hexadecimal characters.
In an IPv6 address, how many bits represent the network protion and the interface portion of the address?
64 bits each.
What is the typical IPv6 address for a localhost?
::1/128
What is the IPv6 network address reserved for multicast?
ff00::/8
What is the IPv6 network address reserved for link-local addresses?
fe80::/10
What is an IPv6 link-local address?
An unroutable address that the system uses to talk to other systems on the same network link.
What are the two methods of IPv6 dynamic address configuration?
DHCPv6 and SLAAC (StateLess Address AutoConfiguration)
In what file does Linux store the hostname to IP address information for name resolution?
/etc/hosts
