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Results: 54
What does DNSSEC verify and not encrypt?
DNSSEC and encrypted DNS solve different problems. When evaluating the accuracy of name resolution, it is necessary to separate data source authentication from transport confidentiality.
DoH and DoT: two transport methods for encrypted DNS
DNS over HTTPS and DNS over TLS serve to transport encrypted queries between the client and the resolver. Knowing which one is used is important during diagnosis.
Does a reverse DNS record prove the real name of the device?
The DNS name appearing next to an IP address makes the inventory readable; but it is not definitive proof of device identity. Maintain the origin and currency of the name.
Why don't mDNS and .local names appear on every network?
The printer or media device may appear in one room with a .local name but not in another VLAN. Understanding the scope of local discovery prevents mistaking it for a device malfunction.
Service discovery with DNS-SD: name, port and destination together
Knowing the device's IP address does not always tell you which port the service it offers is located on. DNS-SD records can present service information in a more structured format.
DNS does not use UDP 53 only
Checking only UDP access for DNS is an incomplete diagnostic. Due to situations requiring TCP, some queries may work while others may fail.
Windows network diagnostics: top five read-only checks
When a network problem occurs, save the current status first instead of resetting all settings. Five simple checks distinguish whether the problem is at the local link, route, DNS or application layer.
No ping response but device works: why?
Interpreting ping failure directly as the device being turned off will result in missing inventory. ICMP response and application service availability are different signals.
Why are TCP and UDP port results interpreted differently?
TCP and UDP are separate transport protocols even though the port number is the same. The result on one does not automatically indicate the status of the service on the other.
How to select scan timeout?
Shorter waiting time does not always mean better scanning. Strike a measurable balance between speed and the need to be able to find slow-responding devices.
Measurement plan for accurate speed testing
No single speed test will indicate the capability of your connection under all conditions. For comparable results, keep the device, connection type and test time constant.
Mbps and MB/s difference: calculate download time
Mbps in the internet package and MB/s on the download screen are different units. Comparing the numbers directly can give the illusion that the connection is eight times slower.