MindMap Gallery Network reference model
This is a mind map about the network reference model. The main content includes: TCP/IP reference model. application layer, Transport layer, network layer, data link layer, etc.
Edited at 2024-03-27 14:26:50This is a flowchart illustrating the process of archiving monthly failure analysis reports and tracking the implementation of improvement measures. The diagram is structured into five main steps, each with specific tasks and sub-tasks.Monthly Report Collection & Organization: This step involves collecting failure analysis reports from various departments, reviewing them for completeness, and categorizing them by product, failure mode, and severity. Root Cause Analysis & Statistics: Here, the focus is on categorizing causes, analyzing trends, identifying root causes, and compiling statistics on high-frequency failure modes and key components. Improvement Measure Formulation & Assignment: This step includes formulating improvement measures, assigning responsibilities, and setting timelines for implementation.Measure Implementation Tracking & Verification: It involves tracking the progress of implementation, verifying effectiveness, and confirming issue closure.Knowledge Base Update & Monthly Report Output: The final step covers archiving reports, updating the knowledge base, and compiling monthly summaries.This template can be easily reused and adapted using tools like EdrawMind to suit different organizational needs.
This is a timeline infographic detailing the annual product certification acquisition countdown process, structured into four sequential phases. The first phase, Certification Planning & Initiation, encompasses goal setting, timeline planning, resource preparation, defining specific certification objectives such as CCC/CE/FCC, formulating an annual plan with key milestones, and allocating necessary budget, personnel, and sample resources. Following this, the Application & Testing Phase involves material submission, coordination with certification agencies, core testing procedures, preparation of technical documents, application forms, and samples, selection of the appropriate certification agency, and execution of critical safety, EMC, and RF tests. The subsequent Rectification & Acquisition Phase focuses on addressing and rectifying any identified issues, re-verification processes, acquisition of the certificate, analysis of test issues, implementation of necessary fixes, and modification of samples for supplemental testing. Finally, the Countdown Monitoring phase emphasizes tracking progress, managing risks, monitoring remaining days and key milestones, managing time, technical, and cost risks, and maintaining effective internal and external communication throughout the process. This comprehensive template can be readily reused and adapted using tools like EdrawMind to meet diverse organizational requirements.
This is a flowchart detailing the weekly update and review plan for technical documents. The process is divided into six main stages, each with specific tasks and responsibilities. It begins with Weekly Planning, where the document scope is defined, update objectives are set, and schedules are arranged. Next, Document Updates involve maintaining various documents such as hardware design documents, test specifications, and BOM tables, alongside version control and archiving. Internal Review Preparation follows, focusing on compiling review materials, identifying participants, and setting agendas. The Review Meeting stage includes document examination, problem discussion, decision recording, and responsibility allocation. After the meeting, Review Feedback Processing takes place, involving issue tracking, document modification, quality checks, and closure verification. Finally, Output Deliverables are prepared, including official release versions, release notifications, review reports, and plans for the next week. This structured approach ensures systematic and efficient management of technical documents, and the template can be easily adapted using tools like EdrawMind.
This is a flowchart illustrating the process of archiving monthly failure analysis reports and tracking the implementation of improvement measures. The diagram is structured into five main steps, each with specific tasks and sub-tasks.Monthly Report Collection & Organization: This step involves collecting failure analysis reports from various departments, reviewing them for completeness, and categorizing them by product, failure mode, and severity. Root Cause Analysis & Statistics: Here, the focus is on categorizing causes, analyzing trends, identifying root causes, and compiling statistics on high-frequency failure modes and key components. Improvement Measure Formulation & Assignment: This step includes formulating improvement measures, assigning responsibilities, and setting timelines for implementation.Measure Implementation Tracking & Verification: It involves tracking the progress of implementation, verifying effectiveness, and confirming issue closure.Knowledge Base Update & Monthly Report Output: The final step covers archiving reports, updating the knowledge base, and compiling monthly summaries.This template can be easily reused and adapted using tools like EdrawMind to suit different organizational needs.
This is a timeline infographic detailing the annual product certification acquisition countdown process, structured into four sequential phases. The first phase, Certification Planning & Initiation, encompasses goal setting, timeline planning, resource preparation, defining specific certification objectives such as CCC/CE/FCC, formulating an annual plan with key milestones, and allocating necessary budget, personnel, and sample resources. Following this, the Application & Testing Phase involves material submission, coordination with certification agencies, core testing procedures, preparation of technical documents, application forms, and samples, selection of the appropriate certification agency, and execution of critical safety, EMC, and RF tests. The subsequent Rectification & Acquisition Phase focuses on addressing and rectifying any identified issues, re-verification processes, acquisition of the certificate, analysis of test issues, implementation of necessary fixes, and modification of samples for supplemental testing. Finally, the Countdown Monitoring phase emphasizes tracking progress, managing risks, monitoring remaining days and key milestones, managing time, technical, and cost risks, and maintaining effective internal and external communication throughout the process. This comprehensive template can be readily reused and adapted using tools like EdrawMind to meet diverse organizational requirements.
This is a flowchart detailing the weekly update and review plan for technical documents. The process is divided into six main stages, each with specific tasks and responsibilities. It begins with Weekly Planning, where the document scope is defined, update objectives are set, and schedules are arranged. Next, Document Updates involve maintaining various documents such as hardware design documents, test specifications, and BOM tables, alongside version control and archiving. Internal Review Preparation follows, focusing on compiling review materials, identifying participants, and setting agendas. The Review Meeting stage includes document examination, problem discussion, decision recording, and responsibility allocation. After the meeting, Review Feedback Processing takes place, involving issue tracking, document modification, quality checks, and closure verification. Finally, Output Deliverables are prepared, including official release versions, release notifications, review reports, and plans for the next week. This structured approach ensures systematic and efficient management of technical documents, and the template can be easily adapted using tools like EdrawMind.
Network reference model
TCP/IP reference model
Application layer
DHCP
Dynamic Host Configuration Protocol Function: It can automatically assign TCP/IP parameters such as IP address, subnet mask, default gateway, and DNS server IP address to the client.
HTTP
Hypertext Transfer Protocol Function: A rule for data transmission between client and server
FTP
File Transfer Protocol Function: One of the standard protocols used for file transfer over the network. It allows users to transfer files between clients and servers and provides an easy way to manage the file system.
TELNET
Remote Terminal Protocol Function: A network protocol used to log in to a computer or device remotely. It allows users to connect to a remote host through the network and execute commands, view and modify files on the host. Port number 23
SSH
Secure Shell Protocol Function: Used to securely log in remotely and execute commands on the network. It provides confidentiality and integrity of data transmission over the network by encrypting the communication session and provides a mechanism to authenticate the remote server Port number 22
transport layer
TCP
Transmission Control Protocol Connection-oriented, byte stream-based transport layer protocol Port number: 6
three handshakes
handshake process
The party that actively closes the connection sends a TCP segment with the FIN (Finish) flag to the other party. This indicates that the sender has finished sending data and wishes to close the connection.
After the other party receives the TCP segment with the FIN flag, it will send a TCP segment with the ACK (Acknowledgement) and FIN flag to the sender.
After the other party receives the ACK, it will send a TCP segment with the FIN flag to the sender. This means that the other party has also completed sending data and hopes to close the connection.
Sliding window mechanism: The sliding window mechanism of TCP (Transmission Control Protocol) is a flow control mechanism used to control the data transmission rate between the sender and the receiver to ensure the effective utilization and stability of the network. This mechanism is implemented by adjusting the window size of the sender and receiver.
wave four times
waving process
The sender (Client) sends a TCP segment with the FIN (Finish) flag to the receiver (Server), indicating that the sender has no data to send but can still receive data.
After receiving the FIN, the receiver sends an acknowledgment (ACK) segment to the sender, indicating that the sender's shutdown request has been received.
The receiver (Server) may also have data to send, so before closing, it will first send a TCP segment with the FIN flag to the sender.
After receiving the FIN from the receiver, the sender sends an acknowledgment (ACK) segment to the receiver, indicating that the close request has been received.
UDP
User Packet Protocol Simple, connectionless oriented transport layer protocol Port number: 17
Network layer
Static routing
dynamic routing
RIP
Routing protocol based on distance vector Function: Measure the quality of a path based on the distance between routers. Choose the best route. The metric is the number of hops.
IS-IS
Link-state-based Interior Gateway Protocol Function: Determines the best path by exchanging link-state information between routers in the network.
negotiation process status
1. Neighbor Relationship State: Down state: initial state, indicating that the neighbor relationship has not yet been established. Init status: Indicates that it is waiting to receive the Hello message from the other router. Up state: Indicates that the neighbor relationship has been established and routing information can be exchanged. 2-Way state: Indicates that both parties have confirmed each other's existence, but have not yet reached a neighbor agreement.
2. Router State: L1 status: Indicates that the router is in the Level 1 area. L2 status: Indicates that the router is in the Level 2 area. L1/L2 status: Indicates that the router is in both Level 1 and Level 2 areas.
OSPF
Open shortest path first protocol based on link status Function: Calculate the shortest path through the Dijkstra algorithm and select the best path to transmit data packets. The metric is the overhead
negotiation process status
Down: Initial state, indicating that the OSPF process has been shut down and the router has not yet established any neighbor relationships.
Init: Indicates that the router is trying to send a Hello message to another router to establish a neighbor relationship.
2-Way (bidirectional): Indicates that the two routers have successfully exchanged Hello messages and each other is aware of the other's existence, but has not yet established a complete neighbor relationship.
Exstart: In this state, the router determines who will act as the Master and begins exchanging database descriptor (DD) messages between the Master and Slave.
Exchange: In this state, the router exchanges LSA Summary List (LSA Summary List), which is used to describe the link status information it possesses.
Loading: In this state, the router requests the missing link status information from the neighbor router based on the received database descriptor (DD) message request and starts loading.
Full: Indicates that a complete neighbor relationship has been established between routers, all link status information has been successfully exchanged, and data can be forwarded.
Negotiation process message type
Hello Packet: used to discover neighbor routers and establish neighbor relationships. The Hello message contains the router's ID, area ID, priority and other information, and is used to confirm the existence of other OSPF routers in the network.
Database Description Packet (DD packet for short): used to describe summary information of the link state database (LSDB) owned by the router. The DD message contains the LSA sequence number, LSA type and other information, and is used for database synchronization between neighboring routers.
Link State Request Packet (LSR message for short): used to request a neighbor router to send an LSA it owns. When it is discovered that an LSA owned by a neighbor router does not exist in the LSDB of the local router, an LSR message is sent to request the details of the LSA.
Link State Update Packet (LSU message for short): used to send detailed information of an LSA owned by the local router to neighboring routers. When an LSR message is received to request an LSA, an LSU message is sent to provide the corresponding LSA content to the neighbor router.
Link State Acknowledgment Packet (LSAck message for short): used to confirm receipt of LSU messages. After receiving the LSU message, the neighbor router will send an LSAck message to confirm receipt. LSAck messages are also used to confirm receipt of LSR messages.
BGP
Border Gateway Protocol Function: Used to exchange routing information between different autonomous systems (AS).
EBGP (External BGP): EBGP refers to the BGP neighbor relationship between two different ASs. When two adjacent routers belong to different autonomous systems, the BGP neighbor relationship between them is the EBGP relationship. EBGP neighbor relationships are usually used to exchange routing information between different ISPs or to connect different enterprise networks.
IBGP (Internal BGP): IBGP refers to the BGP neighbor relationship within the same AS. When two adjacent routers belong to the same autonomous system, the BGP neighbor relationship between them is an IBGP relationship. IBGP neighbor relationships are usually used to disseminate routing information within an autonomous system to ensure that all routers understand the complete routing information within the AS.
The basic idea of route reflection is to create a BGP route reflector (Route Reflector) within an AS, which is responsible for disseminating routing information to other IBGP routers. Other IBGP routers send routing information to the route reflector instead of sending it directly to all IBGP neighbors. The route reflector will then disseminate the received routing information to other IBGP routers, thereby realizing the distribution of routing information.
Route introduction
Routing Blackhole: Routing blackhole refers to the existence of some invalid or unreachable routes in the network, causing data packets to be routed to a non-existent address or an unreachable destination, and eventually discarded. This situation may be caused by configuration errors, network failures, or routing algorithm problems.
Blackhole Route: Blackhole routing means that a special route is set up in the network to discard all incoming data packets without forwarding them. This kind of routing is usually used to defend against DDoS (Distributed Denial of Service) attacks or when network traffic is overloaded. Attack traffic is introduced into blackhole routing to reduce the impact on the network.
address translation
Static NAT
A one-to-one address mapping technology that maps a private IP address to a public IP address. This mapping relationship is fixed and will not change with time or changes in the number of connections. Static NAT is usually used for servers and other devices that need to provide external services.
Dynamic NAT
A many-to-many address mapping technology that dynamically maps a private IP address to an available IP address in a public IP address pool. The mapping relationship is dynamically adjusted as time or the number of connections changes. Dynamic NAT is commonly used for client hosts in large networks to access public network resources.
routing control
policy routing
Through policy routing, data packets can be directed to different exits or paths based on factors such as source address, destination address, service type, packet size, etc. Function: Can be used to implement network management purposes such as traffic engineering, load balancing, and failover.
Routing strategy
The priority and behavior of routing can be determined based on conditions such as source address, destination address, protocol type, etc. Function: Optimize network performance, improve security, and implement specific network requirements, such as limiting traffic, filtering malicious traffic, etc.
data link layer
How the switch works
Forwarding: Once the switch learns the MAC address of the destination host and the corresponding port information, it can directly forward the data packet to the destination port without flooding. Forwarding means that the switch determines which port the data packet should be forwarded to based on the learned MAC address table, and delivers the data packet to the destination as quickly as possible.
Discarding: Sometimes, the switch may not be able to forward data packets correctly for some reasons, such as the destination MAC address is not in the MAC address table, or the port is faulty. In this case, the switch will discard the packet to prevent it from unnecessary propagation in the network, while reducing network congestion and resource waste.
Flooding: When a switch receives a packet but cannot determine which port the packet should be forwarded to, it broadcasts the packet through all ports except the receiving port. This process is called flooding. Flooding ensures that packets reach their destination and also helps in learning the topology in the network.
The MAC address table is a data structure in the switch that records the correspondence between MAC addresses and ports. When the switch receives a data frame, it checks the source MAC address in the frame, associates it with the port that received the frame, and then records this correspondence into the MAC address table. When a data frame needs to be forwarded, the switch will query the MAC address table, find the port corresponding to the target MAC address, and forward the data frame to the port. This can prevent data frames from being propagated in the network and improve the transmission efficiency of the network. The MAC address table is dynamically updated and will be continuously updated based on the data frames continuously sent in the network to ensure that the records in the table are consistent with the network topology.
spanning tree protocol
It is used to solve the network loop problem caused by building redundant links at the core layer of the network.
(Spanning Tree Protocol, STP) is a network protocol used to prevent loops in Ethernet networks with redundant connections and ensure network stability and reliability. STP selects an optimal path to shield redundant connections in the network to build a loop-free tree topology.
Rapid Spanning Tree Protocol (RSTP) is an improved version of STP. Its main feature is that when the network topology changes, the spanning tree is recalculated faster and network availability can be restored faster.
Multiple Spanning Tree Protocol (MSTP) is a protocol that supports multiple spanning tree instances, allowing network administrators to divide the network into multiple areas and assign an independent spanning tree instance to each area to improve network resource utilization. and flexibility. MSTP is defined by the IEEE 802.1s standard and combines the fast convergence features of RSTP with the flexibility of VLAN. It is a commonly used spanning tree protocol for enterprise-class Ethernet switches.
Virtual LAN/VLAN
subtopic
Switch interface type
Access
Receive (RX): In the receive direction, the "Access" interface of the switch receives data frames from the terminal device. When the terminal device sends a data frame to the "Access" interface of the switch, the switch will process the data frame, including decapsulating the Ethernet frame, checking the target MAC address, etc. If the frame's destination MAC address matches an entry in the switch's MAC address table, and that entry indicates that the packet should be sent to a specific port through that "Access" interface, the packet will be forwarded to that port.
Send (TX): In the send direction, the "Access" interface of the switch sends data frames to the connected end device. When the switch receives a packet that needs to be sent to a specific "Access" interface, it sends the packet to that interface and encapsulates it into an Ethernet frame. After the network card of the terminal device receives the data frame, it will decapsulate it and pass the data packet to the device or application connected to the network card for further processing.
Trunk interfaces are used to transmit data of multiple VLANs between switches or between switches and routers. It allows data frames of multiple VLANs to be transmitted over a single physical link, and VLAN tags are usually used to distinguish different VLANs. Data frames on the trunk interface are usually tagged using the IEEE 802.1Q standard to identify and distinguish different VLANs during transmission. Trunk interfaces are usually configured to allow all VLANs to pass through, and are a key part of the transmission of VLAN information between different devices in the network.
The Hybrid interface is a flexible interface type that can transmit untagged data frames and tagged data frames at the same time. This interface type is usually used to connect links between network devices and terminal devices, allowing the simultaneous transmission of different types of data frames, including untagged data (access data) and tagged data (trunk data). Hybrid interfaces typically require administrator configuration to determine which VLANs are tagged (trunk) and which are untagged (access), and can be flexibly configured based on specific network needs.
The process of subnetting involves steps such as determining requirements, selecting subnet masks, calculating subnet ranges, dividing subnets, and configuring network devices. The principle is to use subnet masks to distinguish network bits and host bits, and pass Increase the number of network bits to divide more subnets.
physical layer
RG45 twisted pair
optical fiber
coaxial cable