Storage and Servers

[M-Callahan]

Here is a picture of my server with the disk array..  Just waiting for sims card for router.  Once online will be able to download new OS.  On phone now have monster download right now. 1.65 gigs download speed at 65 k per second.  Will finnishing this project soon.  Cabinet from old zenth tv I use to store booksin it for years.  My dad took the tevelson out of cabet It been in the family for decades.  I believe it has been around since the fifties.

[M-Callahan]

For those who don't Know what I am talking about.  Hopefully this will bring you up to speed.


For those who wonder what I am posting about IP address know as the Internet Protocol Address, it is a numeric number based on bits in binary numbering system.  An octet is a grouping of 4 binary in number that in a grouping of eight binary bits or number (0 or 1)  also know as an octet represented in decimal numbers from 0 to 255.   Each of these row of number is separated by a period. 
Decimal        Binary
186.27.1.6     10111010.000011011.00000001.00000110

When addressing a website we don't use decimal number or binary system to access a web site, it is rather hard to remember these number so we use word to access these numbers.

 
This is where the URL comes in also know as the Uniform Rescoure Locator.   This is what you type in your web browser to get to the website you want to see.  " The format is standardized as <the method of protocol to be used://the domain name/the directory name/the file name>"  For example <http:www.mywebsite.com/forums/coffeeshop/whatisup.html>  The http: is used to search for the other protocols such as ftp, telnet, gopher etc.  The domain or host name ie www.mywebsite.com is the name of the network or computer you are trying to contact that is in a unique world of its own.  /forums/coffeeshop  /forums indicates a folder or a directory.  /coffeeshop is a subdirectory or a folder in a main folder, all of these names are connected by the slash.  /whatisup.html is a file in the folder and can end with asp, htm, cgi, etc.

Domain names: Identifies one or more  IP address IE  www.mywwebsite.com can either represent one or many IP address.  Use in URL to identify particular web page.
Most of these names are assigned by the InterNIC (Internet Network Information Center).  www.mywebsite.com for example: A domain name is composed of a server (host) Name (www), individual name (mywebsite) and group name(com) and country's name in other countries.  They are divided by periods.

DNS (Domain Name System)

Works like a telephone book system in the Internet World.  Links IP address to domain names. The Domain Name System is managed by Domain Name Server all over the Internet. 

DNS maps a domain name to an IP address.

When a URL is typed into a browser, the DNS server searches for a matchig IP address. (DNS server is set by the Internet Service Provider).  If the DNS server dose not find an enter in its database it will ask the Internet root server, which is the center of all DNS servers.  The root server indicates the DNS server that has a data base for the top level domain.  This process keeps going on until the entry is found. 

Accordingly, the procedure is as follows:

A URL address is entered in the browser.
DNS server translates a domain name into an IP address.
Access the computer of the website and ask the computer to forward the file.
The file is forwarded and the browser displays the file on the computer.

Subnetting is kind alike breaking down or dividing a network into two or more networks, works on the IP address so that a number of computer can work on more than one network.

[M-Callahan]

Just an update in classes I am taking.  Which is Cisco CCNA (200-301)

I am presently learning Subnetting using binary rules.
Network/Subnet Address
  Fill the host portion of an address with binary 0s.
Broadcast Address
   Fill the host portion of an address with binary 1s.
First Host
   Fill hat host portion of an address with binary 0s expect for last bit which is 1.
Last Host
   Fill the host portion of the address with binary 1s, except for the last bit which is set to 0.

Example 1
192.168.1.18/24 or 192.168.1.18 255.255.255.0
192.168.1.18(18 octet is the host portion of the address)
 
Subnet = 192.168.1.0000.0000 = 192.168.1.0
  1^st Host= 192.168.1.0000.0001 = 192.168.1.1
Last Host=192.168.1.1111.1110= 192.168.1.254
Broadcast=192.168.1.1111.1111=192.168.1.255

Example 2
172.16.35.123/20 or 172.16.35.123 255.255.240.0
1^st octet = 8bits
2^nd octet= 8bits
3^rd octet= split in the 3^rd octet
Convert Octet 3 and 4 into Binary since both has host bits.
IP address = 172.16.0010/0011.01111011 = 172.16.35.123
            Network Subnet/ Host
   
          Network Subnet | Host
    Subnet= 172.16.0010|0000.00000000= 172.16.128.0
   1^st Host= 172.16.0010|0000.00000001= 172.16.128.1
Last Host= 172.16.0010|1111.11111110= 172.16.255.254
Broadcast= 172.16.0010|1111.11111111= 172.16.255.255

Example 3
PC with IP Address of 172.16.129.1/17 or 172.16.129.1 255.255.128.0

/17 means that 17 bits of the 32 bits are used for network and the subnet and remaining 15 bits are used for host portion.
Convert 3 and 4 octet into binary since they both have host bits.

IP Address= 172. 16.1|0000001.01111011= 172.16.129.1
      Network Subnet | Host
       Subnet= 172.16.1|000000.000000000= 172.16.128.0   
      1^st Host= 172.16.1|0000000.00000001= 172.16.128.1
   Last Host= 172.16.1|1111111.11111110= 172.16.255.254
  Broadcast= 172.16.1|1111111.11111111= 172.16.255.255

I am happy with this the next step in class is the short method where you have to memorize octets tables, after that is done I think I will use the binary method in subnetting because this seem easier to pick up and use over memorization of a table which can fade from memory over time if not used constantly in a workplace.

[Radkres]

  We used to use this to protect Public computers. Reboot Restore Rx
http://rebootrestore.com/

[M-Callahan]

Yes they are still in business.  My internet provider gives them out for internet access through DSL.

[parkdalegardener]

Didn;t even know ZyXel was even in business any more. Had a couple of their modems back when I was running a BBS many years ago. Loved them. Fast. Bulletproof.

[M-Callahan]

Well those classes I have been taking for networking has paid off.  Today while visiting this site I was hacked again, and the internet for me went down.  So when I shut down the computer and rebooted my router, I made a Wi-Fi scan and it showed me that I had other than my own computers on my LAN.  So I got out a new router I had here and installed it.  I set up IPv6 along with IPV4 with a counter check with mac addresses to enter the LAN and the WAN, also a DMZ was set up too from the router.  It took me a while since ZyXel router GUI is little different than CISCO's router GUI, however the principles are the same and that is what really help out in straitening out this mess. I wouldn't want to share this misfortune with other people.  In addition to the DMZ firewall I also have a firewall on each computer too. Presently I am running a detailed virus scan on two of my computers that are on all the time.  It should take about another 10 hours to complete.  This computer has been scanned before coming back to the web.    Hopefully all of this set up will work or at lease slow down the hackers.  I am doing the scan since there might be tools left behind to get around all the barriers that have been put in place.  I think people who have computers should at lease take classes on networking and security to keep a safe computer environment when come to being on the internet in order to safeguard their privacy and assets.  Some how I think they should call the area I live in Hackers' Ville.     

LAN  = Local Area Network :   WAN = Wide Area Network:  DMZ = Demilitarize Zone (Area that a Fire Wall is on Guard):  GUI = Graphical User Interface:    mac address = media access control address

[M-Callahan]

Presently learning about the OSI model and the seven layers that make up this model.  My how things have changed in the last 40 years. 

[M-Callahan]

Hi RR Knight,


Hope you are doing well.



Taking a network class right now.  And then some more Linux.  Had some trouble with hackers couldn't do to much with computers for a while until I straighten out all things they did after all the fun they had.  Could you suggest a good black box firewall for a WAN/LAN at an affordable price?  Also I am working on the Computers side of this system  and going wireless on most of my computers.  Later when I get to the servers I will now put in dual firewalls in to create a DMZ between the incoming portion to the servers and one for protection to the storage portion of the network.  Being hacked is no fun.  Also are cloud configured firewalls safe?  There are a few out there that are in my price range $150.00 to $300.00.   I am thinking of going wireless between the SAN and the WAN/LAN; the SAN will be hard wired.   

[M-Callahan]

Good one! Had to look it up to get. 


TCP (Transmission Controlled Protocol): Using handshake protocol like SYN, SYN-ACK, ACK      UDP (User Datagram Protocol): No handshake (so connectionless protocol)