TCP/IP protocol suite can be modelled related to OSI. Instead seven layer of OSI, in TCP/IP protocol suite (DoD: Department of Defense), it only has four layers.
1. Proces/Application layer in TCP/IP or DoD model integrates the functions of Application, Presentation, and Session Layer of OSI model : node-to-node communication and control of user-interface.
2. Host-to-Host layer in TCP/IP or DoD model represents the functions of Transport Layer of OSI model : transmission service, reliable communication, ensuring error-free delivery of data.
3. Internet Layer in TCP/IP or DoD model represents the functions of Network Layer of OSI model : logical transmission, IP addressing, routing packets across different network.
4. Network Access Layer in TCP/IP or DoD model represents the functions of Data Link Layer + Physical Layer of OSI model : monitors data exchange between host and network, hardware addressing, defines protocol for the physical transmission of data.
TCP/IP protocol suite in DoD model.
Process/Application Layer
1. Telnet : Terminal Emulation, Allows machine (telnet client) to access resources of other (remote) machines (telnet servers).
2. FTP : File Transfer Protocol, Allows user to transfer transfer file between any machines using it. Protocol + Program (Allow user to do performs certain task by hand).
3. TFTP : Trivial File Transfer Protocol, simple version of FTP, reduced functions and security, but faster than FTP.
4. NFS : Network File System, Protocol specializing in File Sharing, allows different types of file systems to interoperate. Ex : NSF server running in NT server and client in unix allows user to access same file with their normal file system in normal way.
5. SMTP : Simple Mail Transfer Protocol handles email, uses spoole or queued, model of mail delivery.
6. LPD : Line Printer Daemon, Printer Sharing
7. X-Window : Client server operation, Display things trough window server on another computer .
8. SNMP : Simple Network Management Protocol collects and manipulates valuable network information.
9. DNS : Domain Name Service, resolves hostname, changes IP address into hostname and hostname into IP address.
10. DHCP : Dynamic Host Configuration Protocol assigns IP addresses to host. BootP : hardware address must be inputted manually in BootP table. DHCP Provides Information : IP address, Subnet Mask, Gateway address, DNS server, Domain Name, WINS information. using UDP to send broadcast message on FF:FF:FF:FF:FF:FF and 255.255.255.255.
Host-to-Host Layer
TCP ( Transmission Control Protocol )
takes information from application and breaks them into segments, numbers and sequences segments, so that segments can be putted back together in order.
UDP ( User Datagram Protocol )
unreliable protocol, only break information into segments but doesn’t number/sequences the segments, then send it off to destination without any acknowledgement.
Internet Layer
1. IP : Internet Protocol = Internet Layer. it looks each address, using the table, choose the best path to deliver packets.
2. ICMP : Internet Control Message Protocol, provides information about network problems : Destination Unreachable, Buffer Full, Hops, Ping, Traceroute.
3. ARP : Address Resolution Protocol : finds hardware address of known host ip address.
4. RARP : Reverse Address Resolution Protocol : resolves MAC address to ip address.
5. Proxy ARP : Helps Machine reach destination without configuring routing or default gateway.
i have been enjoying two different operating system for last two years. i am common user though, not a programmer or app developer. my dual core laptop has been used two years for helping me with my study in college, and also as a media entertainment for me. 2004, i was enjoying my first experience with computer, what’s inside it? Of course we had Windows, windows 98 or XP that time. In my Junior High School, computer began to be one of the most needed thing. We, as students are required to understand how the computer work, and we had to know basic knowledge about it.
Windows was the first flavor, we tasted the beauty of the computer by learning about ms word and excel, text editor or words application and spreadsheet respectively. There were also some games, such as the sims, fifa, dll. it was amazing to experience those old games. there was also internet, internet explorer let us to browse email sites like yahoo and hotmail. in my small village though we are a consumer, i my self was not a nerd. so that was my first experience as technology consumer. i didnt know anything about opensource, and not knowing that operating system wasnt only windows XP. Windows has gave us many thing to taste, from beautiful words application, spreadsheet, and also many games and applications. All i know those was bundled in .exe form, and not free of charge. All this applications and operating systems itself were expensive actually. Well, not sure its lucky or not, we can found many cracked software and games, many list of serial number and keys, It is really not legal, but we just dont realize and consider it much. what we considered that time just whether or not we can get the software and games run well on our old computer.
Now is the days if technology, term Open Source is announced everywhere and every time because of its major advantages over windows.
from wikipedia
Open-source software (OSS) is computer software that is available in source code form: the source code and certain other rights normally reserved for copyright holders are provided under a software license that permits users to study, change, improve and at times also to distribute the software.
maybe these are the major advantages of open source over windows
1. Ability to be modified, remake, redistribute
it suggests us to understand the program or the system better. and actually we can do it by studying from its sources. some people say it is nice because we may knowing better how program work than just use it for ordinary use.
2. Easy of access and the low (no) price
some opensource come with really low price and some of them come with no charge or free.
Some other better things for open source over proprietary software are (Scholars Casson and Ryan)
Security
Affordability
Transparency
Perpetuity
Interoperability
Localisation
Well, know the world of open source comes to us. we should be ready to face it. Windows and its (mostly) proprietary software now still the best for some major applications, and for this reason i still love to use windows. There are many free software too actually, and many ways to learn how to create application that can run on windows. but the term open source and its goal is even more beautiful. From my dual boot ubuntu i learn how Open Source work, i experience the nice service they give, and i’d love to learn more about it too.
Gravatar or global avatar is nice service that enables us to share our avatar anywhere. The main function of this service or application is to add our profile, including photos and short explanation about us into our web page. In wordpress this application is useful in comments. We can put our photos to our comments on our own site and also on the other site.
Gravatar is not enable by default in wordpress. It is on separate .com site. To enable this gravatar in wordpress u just need to signup to gravatar.com with your email address that u use in wordpress. there is the step to make it work.
1. Go to your wordress dashboard, Settings, choose General.
2. Check or fill the email address
3. Open new tab, www.gravatar.com
4. Sign up to gravatar.com with the same email address on your General Setting wordpress
5. Confirm your gravatar account on your inbox email
6. Log-in to gravatar.com, upload some images, Try make new comment, it will works
Some other explanation can u find in wordpress.org/codecs
There is some considerations we have to make when we first come up with planning to install software. One of them is what kind application we will run in PC. It becomes a problem when our software doesn’t meet the requirement of hardware and OS.
Such a problem may exist for different architecture (32bit or 62bit (high-end)), mostly it comes from software with it’s specific environment so that it’s failed to install in any different system that miss match the requirement. The other problem is program and memory access issue. Theory says that 32bit hardware/processor can only access memory address up to 4Giga or 2^32 address. So it’s impossible for us trying to install 64bit software in 32bit architecture and wanting it to run well. but different things happen when we tried to install 32bit program in 64bit architecture. Most OS support this with different solutions.
As a (still) biggest OS, Microsoft may found this problem happen many times. So it comes with compatibility options to overcome the problem of different windows version released. Such options exist for windows common user. While for user that wants to maintain Windows server, Windows comes up with WoW64.
To solve the problem first i follow the instructions from those website. but i still couldn’t make it run well, firefox still couldn’t play the flash video in website. i then add 1 more step
use your firewall to block all exe files in the game’s intsall directory from going online.
blocking program to access internet can be done by setting in windows 7 firewall. Step by step to block program using windows 7 firewall :
1. Open start, write firewall in search program and files
2. Choose allow a program through windows firewall.
3. In new window that appear choose ‘Change Setting’ to enable you to edit firewall rules for each program.
4. Find program names that you want to block, for example Pro Evolution Soccer
if you want to block the program from accessing the internet, make sure the check box is empty.
if you fill the check box before program names, it means you allow this program to access the internet. Removing the check in the check box before the program name means you block/disallow this program to access the internet.