Comptia A+ Chapter 7 - Introduction to TCP/IP
Default subnet masks are not the only subnet masks that can be used. ______ provides additional addressing flexibility
(CIDR) Classless inter-domain routing
What is the Default subnet mask for Class A?
(First Octet 1-126) Default Subnet Mask: 255.0.0.0
What is the Default subnet mask for Class B?
(First Octet 128-191) Default Subnet Mask: 255.255.0.0
Summary of the characteristics of IPV4
- Uses a 32-bit address to identify a network connection -Four octets, each are 8bits, separated by dots (192.168.254.255) -256 options for numbers (0-255) in each octet -Provides for more than 4 billion unique addresses
There are ____ Class A networks available.
126
IPv6 uses __-bit addresses.
128
Class A networks can have up to ___ hosts.
16,277,214
3 different examples of subnet masks
192.168.1.15/24 255.255.255.0 11111111.11111111.11111111.00000000
A subnet mask could look like
255.255.255.0
The number ___ is the highest number you will ever see in IP addressing, and pitmans that all bits in the octet are set to ___
255; 1
What does ARP do?
Address Resolution Protocol resolves logical IP addresses to physical MAC addresses
Neither network ID nor the host ID can be set to
All 1's or all 0's. A host ID portion of all 0's means 'this network' A host ID portion of all 1's means it will broadcast
What is a host?
Any machine or interface that participates in a TCP/IP network, whether as a client or a server.
What is AFP?
Apple Filing Protocol. Is similar to FTP because it was the default file transfer protocol on Mac OS. Developed for use with AppleTalk
What is APIPA?
Automatic Private IP Addressing is used when a computer cannot contact the DHCP server to receive an address. The computer randomly chooses an address starting from 169.254.0.1 with a subnet mask of 255.255.0.0.
What are the three IPv4 address classes?
Class A Class B Class C
What are the three private IP address ranges? Their default subnet mask? term-86 Number of hosts? (IM!)
Class A - 10.0.0.0 - 10.255.255.255 Default subnet mask: 255.0.0.0 # of hosts: 16.7 million Class B - 172.16.0.0 - 172.31.255.255 Default subnet mask: 255.240.0.0 # of hosts: 1 million Class C - 192.168.0.0 - 192.168.255.255 Default subnet mask: 255.255.0.0 # of hosts: 65,536
Describe Class B networks. What size are they designed for?
Class B networks always have the first bit set at 10 (values from 128-191) They are designed for medium sized networks.
Describe class C networks Designed for what kind of networks?
Class C networks have the first three bits set at 110 (decimal values from 192-223) Designed for smaller networks. Most companies have class C.
What are the 4 protocols found in the internet layer?
IP (*MAIN PROTOCOL*) ICMP (Internet control message protocol) ARP (address resolution protocol) RARP (Reverse ARP)
What is IMAP?
Internet Message Access Protocol A secure protocol designed to download emails. It works in connected/ disconnected modes unlike POP3 & simultaneously allows different devices to be connected to one inbox. Designed to replace POP3 bc it wasn't as secure.
How many bits is an IPv4 address?
It's a 32 bit hierarchical address that identifies a host on the network. Hierarchical means that the numbers at the beginning of the address identify groups of computers that belong to the same network.
What is LDAP?
Lightweight Directory Access Protocol Designed to access info from an LDAP directory or database. basically provides us with constant access to phone books, contact lists, and configuration lists. It can use ACL's (access control lists) to set up who can read & change entries on the database. Common analogy: LDAP Provides the access & structure behind the network's phonebook.
Where does NAT run?
Network Address Translation runs on your router
Each IP address is made up of two components: Which one comes first
Network ID and host ID. Network always comes first
What is the protocol most often used to send email messages?
SMTP Simple Mail Transfer Protocol
What is the most current version of SNMP?
SNMP 3
Name the different process/application layer protocols
Telnet, FTP, LPD, SNMP, TFTP, SMTP, NFS, HTTP
The structure of TCP/IP is based on what model?
The DOD (Department of Defense) model.
What is DNS?
The Domain Name System resolves host names to IP addresses through a DNS server. Basically, is uses the DNS server to convert the host URL into an IP address so that computers can communicate.
What are the two Host-to-Host layer protocols?
TCP (transmission control protocol) and UDP (user datagram protocol)
What is TCP and UDP used for?
TCP - web and email UDP - broadcasting/streaming videos
What protocol/port does POP3 use?
TCP 110
What protocol/port does IMAP 4 use?
TCP 143
What protocol/port does FTP use?
TCP 20, 21
What protocol/port does SSH use?
TCP 22
What protocol/port does Telnet use?
TCP 23
What protocol/port does HTTPS use?
TCP 443
What protocol/port does HTTP use?
TCP 80
Major difference between TCP and UDP?
TCP guarantees packet delivery. UDP does not. TCP is referred to as connection oriented communication. UDP (User Datagram Protocol) is referred to as connectionless.
What is the most common protocol used on the internet?
TCP/IP Transmission control protocol / Internet protocol
What protocol/port does DNS use?
TCP/UDP 53
Is IPv6 backwards compatible with IPv4?
Yes
What is Telnet? Major disadvantage?
a simple, text-based network protocol that is used for accessing remote computers over TCP/IP network It's insecure. All data is sent in plain text, including passwords.
When an IPv6 address is written as 2001:db8:3C4C::/48 , the number after the slash indicates how many ____
bits are in the routing prefix.
Any computer that has an IP address beginning with 169.254 has not
configured itself/ has not reached DHCP server
Consecutive groups of zero's can be replaced with a
double-colon
What does the NAT service do?
handles the translation of private addresses that aren't routable on the internet and turns them into public IP addresses.
Any device with an IP address is a ____
host
What does an anycast address do?
identifies multiple destinations and packets are sent to the nearest destination
What is the IPv6 address that has the same job as APIPA?
link local address fe80::/10
Address 127 is called a ____ and is used for troubleshooting network adapters
loopback address
The first four fields of an IPv6 address refer to the
network/subnetwork
In binary, 1 equals ___ and 0 equals ___
on; off
What dies a unicast address do?
packets are delivered to a single node on the network
All of the addresses used on the internet are called ____ addresses
public
When an administrator enters the IP configuration manually for each host, this is called _________. What is a major disadvantage?
static IP addressing It's labor intensive
Computers differentiate where the network ID ends and the host address begins through the use of a _____
subnet mask
IPv6 uses 3 types of addresses:
unicast, anycast, and multicast
All host addresses on a network must be ___
unique
APIPA is also known as
zero configuration networking or address autoconfiguration
What is the current version of IMAP?
IMAP4
What is a protocol suite?
A group of protocols that can be used together.
What is a subnet mask?
A mechanism that allows a network device to divide an IP address into a network and host number.
What is a protocol?
A set of rules govern communications, much like a language in human terms
What protocol/port does DHCP use?
UDP 67, 68
What is CIFS?
Common Internet File System. This is the default file/print sharing protocol on Windows. Shares files and printers between computers regardless of OS
What are the two most critical TCP/IP services?
DHCP & DNS Dynamic Host Configuration Protocol & Domain Name System
What is IPv4 typically written as?
Dotted decimal notation (octet) 192.168.10.55
What is DHCP?
Dynamic Host Configuration Protocol (DHCP) Dynamically assigns IP addresses & other IP configuration information to network clients. allows a host to obtain an IP address automatically and to set TCP/IP stack configuration parameters such as subnet mask, default gateway, and DNS addresses.`
What is FTP?
File transfer protocol. Used for transferring files between computers (uploading/downloading) It's both a protocol and an application. Lets you copy and view files. Cannot be used remotely.
What is the Default subnet mask for Class C?
First Octet (192-223) 255.255.255.0
What is the most commonly used Process/Application layer protocol?
HTTP Hypertext Transfer Protocol
What kind of notation does IPv6 use?
Hexadecimal notation Ex: 2001:0db8:3c4d:0000:0000:1234:56ab
What is HTTPS?
HyperText Transfer Protocol Secure Encrypts traffic between the web-server and the client. Connections are secured using either (SSL) Secure Socket Layer or (TLS) Transport Layer Security
What is HTTP used for?
Hypertext Transfer Protocol. Used for managing communication between a web-server and a client - Lets you connect to view internet content The content is not secure because it's transmitted by HTTP. Not good for transferring sensitive information.
The ____ protocol is responsible for delivering error messages.
ICMP (Internt control message protocol)
The ping utility uses the _________ protocol to send and receive packets
ICMP (Internt control message protocol)
In IP address 192.168.10.55, the subnet mask is 255.255.255.0. What is the network and host portion of the IP address?
Network: 192.168.10 Host: 55
Describe Class A networks
Networks defined as those with the first bit set from 0-126. Designed for very large networks
How many networks and hosts can you find in a Class B network?
Networks: 16,384 Hosts: 65,534
Are private addresses routable on the internet?
No, they were intended for use on a private network only so they don't have to be globally unique.
Name the 4 layers of the DOD Model
PHIN Process/ Application (OSI layers 7,6,5) Host-to-Host (OSI layer 4) Internet (OSI layer 3) Network Access (OSI layer 2, 1)
What is POP3?
Post Office Protocol 3 An old email downloading protocol
What hosts on a network need to have static IP addresses?
Printers, servers, routers, and sometimes a certain workstation.
What is RDP?
Remote Desktop Protocol Allows users to remotely access computers
What does RARP do?
Reverse Address Resolution Protocol Resolves MAC addresses to IP addresses
What is SFTP?
Secure File Transfer Protocol. Alternative to FTP when you want to transfer files securely over an encrypted connection.
What is SSH?
Secure Shell Sets up a secure Telnet session. You can login, transfer files, and execute programs remotely
What is SMB?
Server Message Block Similar to File Transfer Protocol, because it's used to provide shared access to files, printers, and other network resources. EXCEPT it gives you more options like connecting to printers and more management options
What is SMTP?
Simple Mail Transfer Protocol Protocol most commonly used to send email messages. It's designed to send only, so it's referred to as a push protocol.
What is SNMP?
Simple Network Management Protocol Gathers and manages network performance info Collects info from router or switch to make sure it's working properly.
DoD Model
The overall functionality between these two models is virtually identical; the layers just have different names.
What does multi-cast do?
The packet is delivered to all nodes on the network. The IPv6 version of broadcasting
True or False? Computers using APIPA can only communicate with other systems using APIPA!
True
True or False? TCP/IP ensures that packets are delivered from one computer to another
True
True or False? TCP/IP protocol can work on different operating systems
True
True or False? DHCP servers provide IP configuration to clients automatically. What is this called?
True. This is called a lease.
What does URL mean?
Uniform Resource Locator
What is an IP address? What does it identify?
Unique ID # for any device on a network. Identifies network and host on which it resides
