Addressing on Networks Chapter 3 Flashcards
How addressing happens in each OSI Layers
What are the two types of IP addresses?
IPv4—IPv4 (Internet Protocol version 4) addresses have 32 bits and are
written as four decimal numbers called octets.
IPv6 (Internet Protocol version 6) addresses have 128 bits and are written as eight blocks of hexadecimal numbers
Ftp is the host name usually given to an FTP server.
Define “Host name” & “Domain Name”
Collectively, the last two parts of a host’s name
(for example, mycompany.com) are called the domain name, which matches the name of the organization’s domain or network. The first part (for example
susan, ftp, and www) is the host name, which identifies the individual computer on the network.
“www” host name assigned to a computer running a web server.
How addressing happens in each OSI Layers
Data Link Layer
A MAC address is embedded on every NIC on the
globe and is assumed to be unique to that NIC
Nodes on a
LAN find each other using their MAC addresses.
How addressing happens in each OSI Layers
Network Layer IP Adress
An IP address is assigned to nearly every interface,
which is a network connection made by a node on a network. An IP address can be used to find any computer in the world if the IP address is public on the Internet.
an IP address is used only at the Network layer.
How addressing happens in each OSI Layers
Transport Layer Ports
A port is a number used by the Transport layer to find an application. It identifies one application among several that might be running on a host.
How addressing happens in each OSI Layers
Application Layer FQDNS(host name and computer names)
Every host on a network is assigned a unique character-based name called the FQDN (fully
qualified domain name), for example, susan.mycompany.com, ftp.mycorrpany.
com, and www.mycompany.com.
How addressing happens in each OSI Layers
Internet Assigned Numbers Authority
Organization that tracks the assignments of IP addresses, port numbers and domain names.(IANA)
Internet Corporation for Assigned names and numbers
A nonprofit organization charged with setting many policies that guide how the internet works
MAC ADDRESSES PART 1(Data Link Layer)
MAC ADDRESES
You can find a network adapter’s MAC address stamped directly onto the NIC’s circuit board or on a sticker attached to some part of the NIC. MAC addresses contain two parts, are 48 bits long, and are written as hexadecimal numbers separated by colons—for example, oo:6o:8C:oo:54:99
MAC ADDRESSES PART 1 (Data Link Layer)
The first 24 bits (six hex
characters, such as oo:6o:8C in our example) are known as the
which identifies the NIC’s manufacturer.
OUI (Organizationally
Unique Identifier)
.
MAC ADDRESSES PART 1(Data Link Layer)
A manufacturer’s OUI is assigned by the IEEE (Institute of Electrical and Electronics Engineers). If you know a computer’s MAC address, you can determine which company manufactured its NIC by looking up its OUI.
The IEEE maintains a database of OUIs and their manufacturers,
which is accessible via the web.The last 24 bits make up the extension identifier or device ID and identify the
device itself.
TCP/IP
Transmission Control Protocol/Internet Protocol and is a suite of communication protocols used to interconnect network devices
(Network Layer)
IP ADDRESSES
IP addresses identify nodes at the Network layer.
Whereas MAC addresses are used for communication inside a network, an IP address is required in order for a device to communicate outside its local network through a gateway device such as a router.
(Network Layer)
Static IP Addresses
You can permanently assign a static IP address to a device, or configure the device to request and receive a dynamic IP address from a DHCP server.
(Network Layer)
DHCP (Dynamic Host configuration Protocol)
A server that manages the dynamic distribution of IP addresses to devices on network.
(Network Layer)
Gateaway
A computer, router, or other device that a host uses to access another network.
(Network Layer)
Default Gateaway
is the gateway device that nodes on the network
turn to first for access to the outside world.
(Network Layer)
Subnet Mask
Also called a netmask; a 32-bit number that helps one computer
find another. A subnet is a smaller network within a larger network. A netmask indicates the bits of an IP address that identify the larger network, while the subnet mask indicates the bits of an IP address that identify a smaller subnet within the larger network.
(Network Layer)
Network ID
The 32 bits are used to indicate what portion of an IP address is the
network portion,and what part is the host portion.
(Network Layer)
DNS server
-servers that are responsible for tracking computer names and their
IP’addresses.
(Netwokr Layer)
IPCONFIG
Utility in a command prompt window to find out the current TCP/IP settings. Helpful using DHCP because an automacally assigned IP address is not reported to the IPv4 properties.
IPv4 Addresses
A 32-bit IP address is organized into four groups of 8 bits each, which are presented as four decimal numbers separated by periods, such as 72.56.105.12. Each of these four groups is called an octet.
Format of IPv4 addresses
The first part of an IP address identifies the network, and the last part identifies the host. When using classful addressing, which is an older method of managing IP addresses ranges, the dividing line between the network and host portions is determined by the numerical range.
DHCP (Dynamics Host Configuration Protocol)
Dynamic IP addresses are automatically assigned by DHCP server each time a computer connects to the network
NAT (NETWORK ADDRESS TRANSLATION)
is a technique designed to conserve the number of public IP addresses needed by a network.
ADDRESS TRANSLATION
A gateway device that stands between a private network and other networks substitutes the private IP addresses used by computers on the private network with its own public IP address when these computers need access to other networks or the Internet.
PAT (Port Adddress Translation)
Assigns a separate TCP port to each session between a local host and an Internet host.
Two Variations of NAT
SNAT (Static Network Address Translation or Source Network Address Translation) The gateway assigns the same public IP address to a host each time it makes a request to access the Internet.
DNAT (Destination Network Address Translation) hosts outside the network address a computer inside the network by a predefined public IP address. When a message sent to the public IP address reaches the router managing DNAT, the destination IP address is changed to the private IP address of the host inside the network.
IPv6 Addresses
Recall that an IPv6 address has 128 bits that are written as eight blocks of hexadecimal numbers separated by colons.
