Network Address A host determine its network address by performing AND operation between IPv4 address and subnet mask. The first address is the network address and the last address is the broadcast address. The source device can determine if the detination device belongs to romote network so that it choose to send the data to…More
Basic Commands of Cisco Routers and Switchs
Introduce some basic commands that issue in the CLI of cisco routers and swithes, including check the status, set up passwords, configure ip and subnet address.More
Ethernet, IPv4 and IPv6 headers
As data travels through the network, it is encapsulated into various headers at each layer of the network model. This process of encapsulation ensures that the data is properly formatted and routed to its intended destination. Let’s examine the different headers that are added to the data as it moves through the network layers.More
Network Basic Concept
Same-layer and Adjcent-layer Interaction Same-layer interaction refers to the communications between the same TCP/IP layer in different devices. Such as a computer transits a Layer 3 packet to another computer, the receiving computer will handle the data at the same layer. Adjcent-layer interaction refers to the communications between upper and lower layers. For example, the…More
MAC Address and IP Address
MAC Address MAC address is 6 bytes (48 bits) long and represented by 12 hexadecimal digits. The first 3 bytes are assigned to the NIC manufacturer by IEEE which is globally unique and is known as the OUI (Organizationally unique identifier). The last 3 bytes are assigned to the device by the vendors, which results…More
OSI and TCP/IP layers
The OSI model defines seven layers, from top to bottom: Application Presentation Session Transport Network Data Link Physical In contrast, the TCP/IP model simplifies this to four layers, from top to bottom: Application Internet Transport Network Access Specifically, the top three layers of the OSI model are consolidated into the Application Layer in TCP/IP, while…More