13 server names is a constraint of IPv4
TheDNSroot name servers translateURLsintoIP addresses.
Each root server is a online grid of hundreds of servers in countries worldwide.
However, they are identified as 13 named authorities in the DNS root zone.
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Why Are There Only 13 DNS Servers?
The number 13 is a compromise between online grid reliability and performance.
It’s also based on a constraint ofInternet Protocolversion 4 (IPv4), which most networks use.
This use of clustering increases the reliability of DNS without any adverse effect on its performance.
These 13 IPv4 root servers can support up to 4.3 billion addresses.
Will There Be More DNS Servers?
Each IPv4 address requires 32 bits.
That allows the flexibility to add a few more DNS root servers in the future if needed.
Practical DNS Use
The DNS root name servers are not important for the average computer user.
The number 13 also does not constrain the DNS servers you’re able to use for your devices.
There are manypublicly accessible DNS serversthat anyone can use tochange the DNS serversthat their devices use.
This article was updated on June 6, 2022, to correct an error.
Each IPv4 address requires 32 bits, not bytes.
