Fundamentals of computer networking

Today, there are two Internet Protocol versions that work within networks.

IPv4

How would you access a private network from the internet?

The private network needs special access via a gateway. It's not possible to access a private network from the internet. A private network can access another private network by using network address translation.

This layer splits the application data into manageable ordered chunks by using the right port for the application protocol that's used. The protocols associated with this layer are TCP and the User Datagram Protocol (UDP).

Transport layer

IPv4 address classes The Internet Protocol's local address space is split into five logical classes or ranges of IP addresses, each represented by a letter of the alphabet.

A through E

The TCP/IP model is made up of four distinct layers. Each layer uses a different type of protocol. Notice how the TCP/IP model

Application layer Transport layer Internet layer Network access layer

IPv6 also introduced several benefits

Simplified network configuration: Security: Security: Multicast and anycast functionality:

___-/____ is an open standard. It's governed, but it's not owned by any one organization, so it works with all operating systems, networks, and hardware.

TCP/IP

What is the DNS?

The DNS helps resolve domain names to IP addresses. It's a hierarchical and decentralized naming system for computers, services, or other resources connected to the internet or a private network.

Parts of an IPv4 address There are two parts to an IP address

the network the host

The ______ _____ is responsible for determining which communication protocols are used. This layer includes HyperText Transfer Protocol (HTTP), DNS, File Transfer Protocol (FTP), Internet Message Access Protocol (IMAP), Lightweight Directory Access Protocol (LDAP), Post Office Protocol (POP), Simple Mail Transfer Protocol (SMTP), Simple Network Management Protocol (SNMP), Secure Shell (SSH), Telnet, and TLS/SSL.

application layer

Also known as the network layer, this layer ensures the data packet gets to its destination. The protocols associated with this layer are IP, IPv4, IPv6, Internet Control Message Protocol (ICMP), and Internet Protocol Security (IPsec).

Internet layer

What is TCP/IP?

It's a protocol used to interconnect network devices on the internet. TCP/IP is a suite of communication protocols that allow different networked devices to communicate with each other.

What is the structure of an IPv4 address?

It's made up of four numbers, in the range 0-255, each separated by a dot. An IPv4 address is made up of four numbers, each separated by a dot. An example is 192.168.0.1.

What is a subnet?

It's the logical subdivision of an IP-based network. Subnets allow your network to be divided into multiple subnetworks.

This layer is responsible for defining how the data is sent across the network. The protocols associated with this layer are ARP, MAC, Ethernet, digital subscriber line (DSL), and Integrated Services Digital Network (ISDN).

Network access layer