Today, I solved "Remove Nth Node From End of List." Description: In this problem, we are gonna delete nth node from the end of the list. For example of case 1, we found the "4" is the 2nd node from the end of the list. But how can we delete and how can we know nth node from the end? Solution: 1. First, we are gonna make two pointers on the list: left and right. 2. "right" is "n" ahead of left. F..
I learned about Ethernet. Ehternet is a physical topology. Here are the two structuresof Ethernet. Bus All nodes in same collision domain (nodes can collide with each other). Star Active switch in center Each spoke runs a seperate Ethernet protocol. (nodes do not collide with each other). Also, Ethernet has many different standareds. Common MAC protocol and frame format. Different Speeds: 2Mbps,..
Today, I learned about APR. Last time, I learned about the LAN address. As this picture described, each LAN has a unique MAC address. Here is the question: How to determine interface's MAC address, knowing its IP address? The Answer is "Refer to APR table." This is the APR table, which we can see on our cmd or terminal. We should know that how APR protocol works in network. Let's have an example..
When we learn about the network, we can see there are two address: IP address and MAC address. So, what is difference between them? ๐ญ IP address: IP address function: It is used globally on the internet to transfer packets from source node to remote destination. Network layer(layer 3) address for node/router interfaces. 32 bit IPv4 address assigned by DHCP server. MAC address (or LAN or physical..
I used the radio check to change the image. Here is my html file. The is the webpage has a boy image. I want to change the image of eye, mouth and nose. As we can see, the image should be changed when I check another radio. I put the "onclick=" to call the javascript function. Each function has two var. "var ~Radio" is for array to get Node from html file. "var ~Image" includes the node from in ..
Today, I leanred about the NAT: network address translation. Why there is a NAT in the real world?? Motivation: what is the problem? Number of IP addresses required in the internet is much more than the 4 billion available IP addresses. If a subnet grows larger than the ISP's IP address range, no IP address will be available for them. Solution: IPv6: larger IP address, more number of IP addresse..
This exercise is for learning how to use Javascript event work on web page. I made the web page for moving picture. Create a document that has a small image of myself. (It should be hidden at first) Regardless of the position of the cursor, the image must appear with the center of the position of the mouse cursor at the time. Included the external CSS file to make red heading on my web page. Her..
We are gonna learn about how to setup PHP on our desktop/laptop. Go Website: www.mamp.info Select right version to your computer Download files and launch it. Click the application: Now, we can start the hosting by clicking "WebStart." localhost is the default name of the computer, 127.0.0.1 is the IP address of the local computer. Place the .php(php files) to under the htdocs folder. However, i..
User Search at root (๋ฃจํธ์์ ์ฌ์ฉ์ ์กฐํ) USE mysql; SELECT host, user FROM user; Give Privileges at root (๋ฃจํธ์์ ์ฌ์ฉ์ ๊ถํ ๋ถ์ฌ) GRANT ALL PRIVILEGES on testdb.* TO ‘testuser’@‘localhost’; Check User (ํ์ฌ ์ฌ์ฉ์ํ์ธ) SELECT USER(); Check current DB (ํ์ฌ DB ํ์ธ) SELECT DATABASE(); Check the data of sepecific table (ํน์ TABLE ๋ฐ์ดํฐ ํ์ธ) SELECT * from (name of table); Check column (Column ํ์ธ) EXPLAIN (name of table); OR DES..
Today, I learned about the DNS in Network programming class. So, What is DNS?? DNS stands for "Domain Name System." In real world, we identifies people with SSN, their name or passport number. Like this, our network server identifies with IP address and "name" like human. DNS is a distributed database. Implemented in a hierachy of many name servers. DNS is an application-layer protocol. Hosts an..
