After some time I have finally some energy to publish a bit more of some stuff about Huawei QoS. The following article will be concentrating on Custom Queuing as it is seen on VRP 3.40 on AR series routers (namely AR46 and AR28).
IPsec overview
IPSec is a framework of symmetric encryption of IPv4 protocol which is good for VPN creation etc. Parts of the IPSec are Internet Key Exchange (binding all the pieces together), Diffie-Hellmanalgorithm (for secure key exchange) and symmetric pre-shared key or certificate based authentication. This main three components make IPSec very reliable and very difficult to break into (even though some of the algorithms are weak/vulnerable).