Pre-sales engineer: the pre-sales position is usually in the manufacturer or integrator. The pre-sales engineer probably doesn’t use the equipment at all. They spend most of their time writing documents. In addition to writing documents, they just communicate with customers. They don’t care how to deal with a certain technical problem. What they know is the difference between the equipment of different manufacturers and models, what function the models have or what they can’t do, as well as the price. The work goal of the pre-sales engineer is to find out what the customer wants and make a plan / bid that makes the customer agree.
After-sales / implementation engineer: the manufacturer, integrator and Party A’s company will have the position of implementation engineer, and the after-sales engineer is forced to work hard. Catching up with the progress and getting the customer / leader to sign the acceptance report are the most troublesome things for the implementation engineer.
Routing and switching direction: it is usually in an integration company or an outsourcing service provider to provide services to government agencies and enterprise users. They can also work in an operator, but the operator focuses on transmission network, wide area network and park access technology. This is the hardest and most competitive direction. There are too many people. I believe people can work after a few months of training. The salary is not very good. Now Cisco has declined. In addition to Cisco, H3C, Huawei and Ruijie are the most popular manufacturers in China. As the market competition is too big, some small integrators often do everything and have limited access to high-end technology. Many people end up being mediocre. They do everything in network, decoration, audio and security, because those companies has to survive.
Network security direction: they usually work in security service providers and relatively large integrators. In addition to understanding the security aspects of routing and switching, it is also necessary to be familiar with the firewall, IPS, signature and verification system, certificate system, monitoring and alarm system of many manufacturers, as well as some hacker attack and defense technologies. It is better to understand scripts and programming. Network security has developed from two different perspectives of network and programming, but in the end, they all have the same goal. The main security product manufacturers are Cisco, PaloAlto, Juniper, CheckPoint, Tianrongxin, Shanshi Netcom and Lvmeng. There are also those who take the low-end routing in security. In the end, they end up scanning for loopholes and patching computers every day.
Operation and maintenance engineer: the position of operation and maintenance is generally Party A, or the integrator outsources to Party A, which is also called on-site. The workload of the operation and maintenance engineers is often smaller than that of the former two. Most of the time, they are idle and have little to do. But once they are busy, they are under great pressure. Although there are not many projects to do, the operation and maintenance engineers need to have strong technical strength, because it is easy to set up a network and make it work. However, it is very troublesome to troubleshoot. If it is not a large-scale company, the professional level of operation and maintenance personnel is usually not so high. Many times, it is required to know more about the network, the host, Linux shell programming and python. It is best to be able to flexibly use various automation tools.