Chapter 2

Primary zone

* Read/Write copy * One primary writable zone

IPv6

-128 bit long -written in hexadecimal notation. -A036:0000.0000.0000.ABCD.0000.0000.C0A -A036::ABCD:0000.0000.C0A -loopback address= 0:0:0:0:0:0:0:0:1

Host id(device Id)

-Identifies the a device within the network.

Net Id(Network Id)

-Identifies the network

There are 2 different types of buses

-Parallel bus -Serial Bus

Motherboard buses.

-are the buses that transfer information from different component of the pc into the CPU.

NIC (Network interface card)

-works in physical and data link layer of the OSI model.

Unicast

1 to 1 communication

Broadcast

1 to all

Multicast

1 to many communications

Functions of NIC

1)connect a computer to the network 2)buffering 3)Packet Filtering 4)Prioritize 5)Keep Statistics

The MAC address, also called the physical 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.

Data Link layer MAC address

DNS

Example of ____ If You type in an web address on web browser, DNS will resolve the web address to a number because the only thing computer knows is number . Yahoo.com, you don't have to type in Yahoo.com to retrieve the web page. You can type in Yahoo's Ip address instead 74.125.44.25, If you already knew what the Yahoo IP address was.

DNS

Example: 1 person talks at a time 2 when the person talks response back is expected 3 specific messages receive specific responses protocols are the rule for communication

is the host name usually given to an FTP server

FTP

-Resolves names to numbers ( Domain name to numbers) -Basically work as phone book

How DNS works?

there is something called NAT-(Network Address Translation)

How does the DEFAULT GATEWAY knows how to convert the IP address into private?

The _____ can be used to find hosts on any computer on the globe if the ____ is public on the Internet.

IP address

for example, 92.106.50.200.

IPv4

Two types of IP addresses are used on the Internet:

IPv4 Ipv6

32

IPv4 address is ____ bits long written in dotted decimal notation 128.36.125.246.

for example 2001:0DB8:0B80:0000:0000:00D3:9C5A:00CC.

IPv6

number

If You type in an web address on web browser, DNS will resolve the web address to a number because the only thing computer knows is ____ . Yahoo.com, you don't have to type in Yahoo.com to retrieve the web page. You can type in Yahoo's Ip address instead 74.125.44.25, If you already knew what the Yahoo IP address was.

addresses have 32 bits and are written as four decimal numbers called octets

Internet Protocol version 4 (IPv4)

addresses have 128 bits and are written as eight blocks of hexadecimal numbers

Internet Protocol version 6 (IPv6)

are not used to find nodes on networks other than the local network

MAC addresses

48

MAC is ___bits long

An IP address is assigned to every interface, which is a network connection made by a node or host on a network

Network layer IP address

secondary zones

Read only copy ~ Can be copies of Primary, Secondary and Active directory integrated can be copies of active directory integrated zones or even other secondary zones * Primary zone must be available to make changes

authoritative name servers.

So once again the resolver will now ask the authoritative name server for the IP address. ______ are responsible for knowing everything about the domain which includes the IP address. They are the final authority.

Primary zone

So there is never a problem with replication conflicts, there is only ever one primary writeable zone when the_____ is not stored in active directory. Any DNS server can hold as many ____ as you wish as long as there is only one_____ on one DNS server at a time.

Primary zone

Stored in a text file ~Easy to back up ~Easy to recover

subnet mask

The 32 bits are used to indicate what portion of an IP address is the network portion and what part is the host portion. Using this information, a computer can know if a remote computer with a given IP address is on its own or a different network.

public IP addresses

The Class A, B, and C licensed IP addresses are available for use on the Internet and are therefore called____________

NetId

The IPv4 address is made up of two parts, the host address (HostId) and the network address (_____).

HostId

The IPv4 address is made up of two parts, the host address (____) and the network address (NetId).

secondary zones

The advantage of having the data in text files is that it is easy to back up and easy to recovery in a disaster. When you are designing your network, keep in mind that the primary zone must be available to make any changes to your dns zone. If the server holding your primary zone is not available, no changes can be made. In order to have redundancy, you need to have the zone data accessible on multiple servers. Since there can be only one primary zone at one time you need another kind of zone file. This is where ________come into place.

zone transfer

The primary DNS server holds the authoritative DNS database for the organization. When a secondary DNS server needs to update its database, it makes the request to the primary server for the update;

secondary zones

The thing to remember with secondary zones is that are read only. If you want to make any changes they must be made on the original zone. When you attempt to change a record on a secondary zone. The secondary will pass the change onto a zone with read write access. The primary zone must be available for changes to be made to the zone. In some environments your DNS server may be stored on a UNIX based system.

authoritative name servers.

The top level domain server stores the address information for a top - level domains, such as .com .net .org and so on. This particular TLD server manages the .com domain which yahoo.com is a part of. So when a TLD server receives the query for the IP address for yahoo.com, the TLD server is not going to know what the Ip address for yahoo.com. So the TLD will direct the resolver to the next and final level, which are the______.

TLD or top level domain server

There are 13 sets of these root servers strategically placed around the world and they are operate by 12 different organizations. Each set of these root servers have their own unique IP address. So when the root server receives the query for the IP address for yahoo.com, the root server is not going to know what the IP address is, but the root server does know where to send the resolver to help it find the Ip address. So the root server will direct the resolver to the _______(4) for the dot-com domain. So the resolver will now ask the _______ (4)for the IP address for yahoo.com.

For example, a Web server application is usually configured to listen for incoming requests at port 80. Transport layer port numbers

Transport layer port numbers

Recall that a port number identifies one application among several applications that might be running on a host and is used by the Transport layer to find an application。

Transport layer port numbers

is typically the host name assigned to a computer running a Web server

WWW

authoritative name servers.

When the___________receives the query from the resolver, the name server will respond with the IP address for yahoo.com and finally the resolver will tell your computer the Ip address for yahoo.com and then your computer can now retrieve the Yahoo web page. It's important to know that once the resolver receives the IP address, it will store it in its cache memory in case it receives another query for yahoo.com so it doesn't have to go through all those steps again.

DNS servers

When you enter a computer name, such as www.cengage.com, in your browser address box, a DNS server is needed to find the IP address of that host.

Resolver sever

When you type in yahoo.com in your web browser and if your web browser or operating system can't find the ip address in its own cache memory, it will send the query to the next level to what it called the ________

Authority zone

_______ means the zone can answers questions about that zone, it does not necessary mean that the records in the zone can be modified. When a record is retrieved from a authority zone it means it is trusted to be correct. A record from not authority server could be incorrect

private IP address

________ is a non-Internet facing IP address on an internal network.

subnet mask

a 32-bit number that helps one computer find another.

cache

a component that transparently stores data so that future requests for that dat can be served faster

Gateway

a computer, router, or other device that a host uses to access another network.

DNS servers

are responsible for tracking computer names and their IP addresses.

MAC address

consist of -physical address -hardware address -ethernet address -adapter address

Every host on a network is assigned a unique character-based

fully qualified domain name (FQDN）

for example, john.mycompany.com, ftp.mycompany.com, and www.mycompany.com.

fully qualified domain name (FQDN）

The first part (for example, john, ftp, and www) is the

host name

identifies the individual computer on the network.

host name

the last two parts of a

host name (for example, mycompany.com) are called the domain name

Tunneling

is a method used by IPv6 to transport IPv6 packets through or over an IPv4 network.

recursive query

is a query that demands a resolution or the answer "It can't be found."

Buffer

is a temporary place

Resolver server

is basically your ISP or Internet service provider

Paging

is the process of transferring memory from the hard drive into temporary memory.

root server

is the top or the root, of the DNS hierarchy

Primary zone

must be available to make changes

TLD or top level domain server

refers to the last segment of a domain name, or the part that follows immediately after the "dot" symbol.

root server

so when the resolver receives the query it will check its own cache memory to find an IP address for yahoo.com, and if it can't find it, it will send the query to the next level which is the ________

matches the name of the organization's domain or network.

the domain name

default gateway

the gateway device that nodes on the network turn to first for access to the outside world.

Iterative queries

the servers only provide information if they have it; iterative queries do not demand a resolution.