Network Design Basics

Open Systems Interconnection Model

The Open Systems Interconnection (OSI) model is a conceptual framework for understanding and designing computer network protocols. It was developed by the International Organization for Standardization (ISO) in the 1980s and is widely used in the networking industry as a reference model for network architecture and design.

The OSI model consists of seven layers, each with a specific function and purpose. The layers are:

1. Physical layer: This layer deals with the physical aspects of network communication, such as the transmission of data over a physical medium like copper wire, fiber optic cable, or wireless radio waves.
2. Data link layer: This layer is responsible for the reliable transmission of data between nodes on a network, using techniques like error detection and correction, flow control, and access control.
3. Network layer: This layer provides routing and addressing functions, allowing data to be transmitted between different networks or subnetworks.
4. Transport layer: This layer provides end-to-end communication services, ensuring that data is transmitted reliably and efficiently between applications running on different hosts.
5. Session layer: This layer manages the establishment, maintenance, and termination of sessions between applications, providing services like session checkpointing and recovery.
6. Presentation layer: This layer deals with the formatting and presentation of data, translating between different data formats, character sets, and encryption schemes.
7. Application layer: This layer provides services and protocols for specific applications, such as email, file transfer, and web browsing.

Overall, the OSI model provides a conceptual framework for understanding how network protocols and services work together to provide end-to-end communication between applications running on different hosts. It has been widely adopted as a reference model for network architecture and design, and is still used today as a basis for network standards and protocols.

Internet Protocol Address

An IP address, short for Internet Protocol address, is a unique identifier assigned to each device connected to a network that uses the Internet Protocol for communication.

An IP address is a only way to identify a device in the network.

An IP address should be unique in the same network to be visible to connected devices.

IP Address & Subnet Mask

How to ensure that each device has a unique IP address in the network.

1. First 3 bytes: Network Part specifies a specific network segment.
2. Last 1 bytes: Host Part specifies specific device in this network.

Private IPv4 Addresses

• Private IP address can not be ussed on public network.
• On public network IP address should be unique in order for hosts to be identified uniquely.
• In different private networks, the IP address can be the same. it is an effective way to save IP addresses.
• According to the standards set by Internet Engineering Task Force (IETF) document RFC-1918, the following IPv4 address ranges are reserved by the IANA for private internets, and are not publicly routable on the global internet.
  • 10.0.0.0 – 10.255.255.255 (/8 prefix)
  • 172.16.0.0 – 172.31.255.255 (12 prefix)
  • 192.168.0.0 – 192.168.255.255 (/16 prefix)

IPv6 Addresses

An Ipv6 is written in hexadecimal notation with colons subdividing the address into eight blocks of 16 bits each.

e.g: 2001:db8:3333:4444:5555:6666:7777:8888, 2001:db8:3333:4444:CCCC:DDDD:EEEE:FFFF.

For Hikvision Cameras, it supports IPv6 with three modes.

1. Manual: Configure IPv6 address manually.
2. DHCP: Obtain IPv6 address automatically from DHCP server.
3. Route Advertisement: Obtain IPv6 address by combining route advertisement and its MAC address.

New Password Strategy

Why the password strategy has changed?

• In the past, we didn’t force installers and users to change the default password.
• Installers have an option to finish the installation without setting up the strong enough password.
• Default usernames and passwords are widely known.

Password Strategy

• No more default password and device activation.
• complex passwords that include uppercase, lowercase, numbers and special characters are recommended.

Lockout Rules

1. Admin has maximum 7 passwords input attempts.
2. Others have  maximum 5 passwords input attempts.

Activation

• Activation of the device can be carried out locally or via the web browser.

What If a Password Is forgotten

• For devices with reset button, the password can be reset by pressing the reset button.
• For devices without reset button, the password can be reset by the following secure methods.
  • Send the device information/Devicekey.xml/QR Code exported from the device within the LAN to Hikvision.
  • Hikvision will provide users with security code/Encrypt.xml

New Password Resetting Strategy

• With this strategy, customers will be able to reset the password by themselves.
  • The user can export the Guide file in advance and reset the password by importing the Guide file when need.
  • The user can set validation questions and reset the password by answering the pre-set questions when needed.
• Local GUI, SADP, iVMS-4200, and web client support new password resetting strategy.
• New password resetting strategy is available for -E/-K/-I series NVR  from V3.4.90 To Turbo 3.0.

Network Introduction

Network is a collection of computers, servers, mainframes, network devices, peripherals or other devices connected with each other to exchange data.

In video surveillance area, the network includes core switch, Ethernet cable, fiber optic cable, IP cameras, and servers, etc.