Check the network and device running status before applying VoIP.

In a recent webcast, we discussed performance management and what to view when you check your statistics. The worst case is to use network utilization as a measure of network health. There are other more valuable statistics. Utilization is very important, but it is only a small part of the network health status.

There are two problems with utilization. First, it is almost impossible to determine when the workstation is in use. Even if a person is sitting at his desk, he may be on the phone and does not use the Internet. Second, many users work locally and store their work on the network after completing the work. Therefore, you must know when the network is actually used to determine how much bandwidth is being consumed. For example, refer to the following two charts:

Figure 1: average usage of a week

Figure 2: average usage of a month

In Figure 1 above, the network usage is measured based on the inbound communication of a week. Figure 2 shows the measurement results of the same line for one month. As you can see, there is a big difference in usage. When planning VoIP, you should assume that the traffic remains in the peak state. If this is not the case, when the processing task increases, your speech signal quality will decrease as your plan is not prepared.

Another important thing is to check the cache space and discarded packets of your electronic devices. A vswitch can discard data packets. When the cache is too full, the switch will discard some data packets and request the sender to resend them. This function is not ideal for voice communication. Although you can set up virtual LAN and priorities, it does not matter if the device is overloaded. In particular, you need to check the discarded packets on the uplink port and the discarded packets on the common port, such as the ports that may connect to the IP switch ).

Some errors you will find in your Simple Network Management Protocol data are also worth investigating. The most important thing is bit errors. This error can be displayed as InErrors and OutErrors. Not all manageable systems allow you to further check the error status. Some systems allow you to perform inspections to speed up troubleshooting. Sometimes when you see these errors, the first thing you should do is test the cabling channel you connect to that port. A simple statement about cable testing is to ensure that the testing device has the latest version of software and firewall and has recently been calibrated. Make sure that your interface and jumper are relatively new. Each interface or jumper has a limited number of plugging times. A channel looks bad on the surface, but it may not actually be bad.

Next, check your duplex settings. Duplex mismatch or automatic negotiation for a half-duplex channel further limits the operation. It is important to have a full-duplex link. Hard configuration or incorrect cabling on the switch or workstation, and the channel exceeding the maximum distance will cause half-duplex problems.
After you fix these errors, You need to perform a 30-day network check. I recommend the 30-day check period to check functions that are not used every day, such as processing at the end of the month. A qualified infrastructure auditor can help with all these steps.