Indicators of a mechanical VOA


Description of indicators related to a mechanical VOA.
For example, Optical Tunable Attenuator,Manual(Single),1300~1610nm,2~30dB,2.0dB,40dB,2mm*2.5m LC/PC. The indicator description is as follows:
1300~1610 nm: supported wavelength range
2~30 dB: supported attenuation range
2.0 dB: insertion loss
40 dB: echo loss
2mm*2.5m: pigtail diameter and length
LC/PC: optical fiber connector type.
The return loss refers to the ratio of optical power returned from the input port of passive components to input optical power. The formula is as follows:
RL = -10 log (Pr/Pj)
Pj refers to the optical power sent to an input port. Pr refers to the optical power received from the same input port. Generally, the return loss of a fixed optical attenuator is 45 dB; the return loss of a mechanical variable attenuator is 40 dB or 55 dB. A larger return loss value indicates smaller optical power returned by the same optical port on a passive component and better the attenuator performance.

Other related questions:
Firewall IPSec mechanism
USG IPSec mechanism What is IPSec? 1. Designed by Internet Engineering Task Force (IETF), IPSec is an open network-layer framework protocol. It is not a single protocol, but a collection of protocols and services that provide security for IP networks, including security protocols such as Authentication Header (AH) and Encapsulating Security Payload (ESP), Internet Key Exchange (IKE), and certain algorithms used for authentication and encryption. 2. IPSec provides following security services for IP packets mainly through encryption and authentication: a. User data encryption: IPSec encrypts user data to ensure data confidentiality. b. Data integrity verification: IPSec ensures that the data is not tampered with during transmission using data integrity verification. c. Data origin authentication: IPSec authenticates data origins to ensure that data comes from real senders. d. Anti-replay: IPSec prevents malicious users from sending captured packets, that is, the receiver discards duplicate packets. 3. Application Scenario a. Connection of LANs Through VPN 1) Site-to-Site VPN Site-to-site VPN is also called LAN-to-LAN VPN or Gateway to Gateway VPN, in which IPSec tunnels are established between the enterprise headquarters and branches. 2) L2TP over IPSec In L2TP over IPSec, packets are encapsulated through L2TP and then IPSec. L2TP authenticates users and assigns IP addresses, and IPSec ensures security. 3) GRE over IPSec IPSec cannot encapsulate multicast, broadcast, or non-IP packets. Therefore, when transmitting the preceding packets over the IPSec VPN, IPSec encapsulates the packets as IP packets using GRE and then encapsulates the packets as IPSec packets. 4) Hub-Spoke VPN In actual networking, the Hub-Spoke IPSec VPN is commonly used for the interworking between the headquarters network and branch networks. b. The IP addresses of mobile devices are not fixed. To avoid attacks from insecure network devices, an IPSec tunnel must be established between a mobile device and the headquarters gateway. The mobile devices can access the headquarters network only after being authenticated by the gateway. In L2TP over IPSec, mobile devices can use the Windows dial-up software, dial-up software supporting IKEv2, or other dial-up software.

Working mechanism of IPSec on AR series routers
Huawei AR series routers support IPSec. Most data is transmitted in plain text on the Internet. This transmission mode has many potential risks. For example, bank account and password data may be intercepted or tampered, and user identities are used, and malicious attacks occur. After IPSec is deployed on the network, transmitted IP data is protected to reduce risks of information leakage. IPSec is a security protocol suite defined by the Internet Engineering Task Force (IETF). IPSec secures data transmission on the Internet through data origin authentication, data encryption, data integrity check, and anti-replay functions. For details, see Configuration Guide-VPN.

If you have more questions, you can seek help from following ways:
To iKnow To Live Chat
Scroll to top