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Articles on networking, security and the internet.
Results: 54
Wi-Fi or internet line? Controlled comparison
To distinguish whether the slow connection is caused by the wireless network or the trunk, take two controlled measurements with the same device. Don't change many variables at once.
QoS and DSCP: what does prioritization change?
QoS can regulate how different traffic is handled during peak times. It is not a magic speed setting that increases the physical capacity of your internet package.
Double NAT: why does the second router confuse things?
When two routers are used at home or in a small office, two separate layers of address translation can occur. This situation is especially confusing in incoming connection and device discovery.
DeleteFile code 5 error in Windows installation
If the installation cannot replace the existing EXE file, an access denied error may appear. Running application, concurrent installation, or folder access are among the possible causes.
Verify the installation file you downloaded with SHA-256
Even if the filename appears correct, it is useful to check that the downloaded package is the same as the released package. SHA-256 comparison is a way to verify file integrity.
Exporting CSV network inventory to Excel without disturbing it
Character encoding and column types are important when opening exported scan results into a spreadsheet application. Incorrect import may change device names or ID fields.
Solid line, dashed line and unknown connection in network map
The usefulness of a network map is not just about looking good. If it is understood what data each link is produced from, it can be used safely in map maintenance decisions.
How do random MAC addresses affect inventory?
The same phone or computer may appear with different MAC addresses. Inventories that do not take into account the use of addresses for privacy purposes may unnecessarily increase the number of devices.
Why is accurate time important in network diagnosis?
If the clocks of different devices do not match, it becomes difficult to understand the sequence of a fault. Time synchronization is the basis for comparing logs and scan records.
I found open port: what should I check now?
Open port is not a security vulnerability by itself. The question is whether the service is necessary, who has access to it, and how it is protected.
Coverage and measurement plan before network scanning
A good discovery study does not start with typing a large range into the address box. The result is more easily verified when the purpose, scope, and expected devices are defined in advance.
How do you compare IP scanners fairly?
The fastest scanner claim is not meaningful unless tools doing the same job are measured under the same conditions. Depth of discovery and accuracy should be compared as well as the number of devices.