(10) the network layer
In the seven-layer OSI model of computer network, the network layer is layer 3. The network layer is responsible for packet forwarding including routing through intermediate routers.
(11) the OSI model
The Open System Interconnection (OSI). It has been developed by ISO - ‘International Organization of Standardization’. It is a 7 layer architecture with each layer having specific functionality to perform. All tese 7 layers work collaboratively to transmit the data fr4om one person to another across the globe.
| Layer | Kind |
|---|---|
| Application Layer | software layer |
| Presentatation layer | software layer |
| Session Layer | software layer |
| Transport Layer | Heart of OSI |
| Network Layer | hardware Layer |
| Data Link Layer | hardware Layer |
| Physical layer | hardware Layer |
(12) a DHCP server and the DHCP protocol
DHCP server: DHCP (Dynamic Host Confivguration Protocol), is a protocol that provides quick, automatic, and central management for the distribution of IP addresses within a network. DHCP is also used to configure the subnet mask, default gateway and DNS server information on the device.
(13) a DNS server and the DNS protocol
Domain Name System (DNS) is the phonebook of internet. Web browsers interact through Internet Protocol (IP) addresses. DNS translates domain names to IP addresses so browsers can load internet resources.
The Domain Network System (DNS) protocol helps internet users and network devises discover websites using human-readable hostnames, instead of numeric IP addresses.
(14) the rules to make 2 devices communicate using IP addresses
- Your computer connects to the router using TCP/IP and asks for a local IP address.
- The router responds and gives your computer the local IP address 192.168.1.12
- Your router requests an IP address to connect to the Internect. The ISP assigns your WAN address as 175.51.127.17
- While on the Internet you request access to the Computer Hope server by entering the URL http://www.computerhope.com. Using DNS that address is translated to an IP address 69.72.169.241 and TCP/IP packet travels over multiple routers and computers until it reaches that address.
- Your TCP/IP packet reaches its destination and communicates with the other computer it responds and repeats the above steps to get the data back to your computer.
(15) IP로 routing이 이루어지는 법
- Routing is the process by which data packets move from one node (machine or device) to another on a computer network until the packets reach the final destination.
The header information includes:
- The IP addresses of the source and destination nodes.
- Packet numbers that help reassemble the packets in the correct order whe the packets reach the destination.
- Other useful technical information.
(16) a default gateway for routing
It allows devices within one network to send information to devises within another network. If you are requestiong a certain web page, the trafic is first sent to your default gateay before leaving the local network to reach its indended destination.
(17) IP관점에서의 port, 그리고 다른 기기와 연결할 때의 사용용도
In computer networking, a port is a communication endpoint. At the software level, within an operating system, a port is a logical construct that identifies a specific process or a type of network service. Ports are identified for each protocol and address combination by 16-bit unsigned numbers, commonly known as the port number. The most common protocols that use port numbers are the Transmission Control Protocol (TCP) and the User Datagram Protocol (UDP).