This page provides a very basic overview of the NUM protocol in its simplest form, for more detailed information about the protocol visit the NUM Protocol website .
The three fundamental components of the NUM protocol are NUM Records, NUM Lookups and Modules:
NUM data is stored in DNS TXT records known as NUM Records. NUM Records are written in MODL , a character-efficient and DNS-friendly data serialisation language. All NUM Records are stored in the DNS under the DNS label
NUM Records are identified using NUM URIs and retrieved via NUM Lookups. NUM Lookups are made by NUM Clients using DNS.
Modules enable standardisation of NUM Record data for particular use cases, e.g. contact information. The data in a NUM Record doesn't have to be based on a module, non-standard records can be used to store NUM Record data of any structure and for any purpose.
Let's take a look at a really simple example.
Storing a NUM record
We're going to store a really simple example NUM record for the domain name
numexample.com. All NUM records start with
@n=1, this identifies it as NUM record using version 1 of the protocol. Here's our record:
We store this record in the NUM Zone for a given domain name. Since we're storing our Hello World example for the domain
numexample.com and it's a non-standard record (`0` is used for all non-standard records), this record is stored in the DNS at
Retrieving the NUM record
Our example record above is identified using the NUM URI
num://numexample.com and can be retrieved using a NUM client.
You can also fetch it manually from the DNS by running a simple command:
- Command Prompt
Storing more data
We can store multiple records for the same domain using paths, similar to the web. The following record is available at the NUM URI
This record is stored in the DNS at
You can fetch it manually from the DNS by running a simple command:
- Command Prompt
Modules standardise the data in NUM records so that it can be understood by devices, apps and services. Importantly, NUM records based on modules can be stored in the DNS in two locations:
- Under the
_numDNS label for the given domain, as we've explored above. This is known as the Independent NUM Zone.
- In the DNS of the NUM Server under the domain
num.net. This is known as the Hosted NUM Zone.
The example NUM record below uses the Contacts module:
The Contacts module is module number 1, so this record can be retrieved using the NUM URI
num://numexample.com:1/ and can be stored in the DNS at either of the following two locations:
- In the Independent NUM Zone at
- In the Hosted NUM Zone at
Records stored in the Independent NUM Zone always take precedence. Records in the Hosted NUM Zone can be managed using the NUM Server's simple user-friendly interface.
To find out more about the NUM Protocol visit the NUM Protocol website .