Ethereum Name Service Explained

(tonal music)
– In this lesson we’re
going to learn about ENS,
or Ethereum Name Service, and
how it helps us provide more
human readable names for our dapps.
ENS is a project within the
Ethereum dev community,
whose goal is to create
a decentralized domain
name registry for the decentralized web.
Today, we use DNS servers
to resolve our dot com
domain names to IP addresses, but a
centralized name registry
like DNS, is vulnerable
to spoofing and denial of service attacks.
Since ENS is built on top
of the Ethereum block chain,
it is decentralized
and doesn’t suffer from
the same vulnerabilities and DNS.
ENS started out on the
Ropsten Testnet, but launched
on the mainnet in May 2017.
The initial proposal describing
ENS and its registration
spec, are EIP137 and EIP162 respectively.
The Ethereum address of
the main ENS contract is
visible on their website,
and we can even go and take
a look at its source code on etherscan.
One thing to note in the
source code, is that ENS
actually maps hashes of
domain names to addresses,
not the actual domain name itself.
This is to prevent spamming
when registering a new
domain, as the name is
never visible in the
contract, only it hash.
This is also a storage
optimization because hashes
take up a constant amount
of space, no matter the
length of the domain name.
ENS is used to resolve human
readable dot eath domain
names to Ethereum account
addresses, smart contract
addresses, IPFS or swarm
contact hashes, and even
more interesting use
cases in the future that
we haven’t thought of yet.
ENS domain names will be
a big step in bringing
mass adoption, as dealing
with long hexadecimal strings
can be daunting to the
average person, and the
strings are just not easy
to remember and pass around.
Another issue that ENS
tries to solve, is that of
domain squatting, people
buying domains because
they think it will be valuable
in the future, and just
sitting on it and never
actually doing anything with it.
This is a popular strategy
in the world of DNS
to make good money, as long
as you bought the domain
name first, you can sell
it to whoever you like
for whatever price.
ENS tries to counter this
with some techniques like
using a vickerey auction to give the
rights to a domain name.
The idea behind the
auction process, is that
the party willing to pay
most for the domain, will
be the one that probably needs it most,
this prevents squatters
from buying another brand’s
domain name early and just sitting on it.
With this auction process,
the brand would also
have a chance to bid on the domain name.
A big difference here from
DNS is that you are not
actually buying the domain name in ENS,
you are simply locking up
ether in a smart contract
that gives you rights to the domain for a
certain amount of time.
If you let go of the
domain name, your locked up
ether is returned to you.
This is in contrast with
DNS where you don’t get
any money back after your domain expires.
There are several ways
you can register a domain
on ENS, even through command
line, but we’re going
to see the simplest way,
which is through their dap
You should give their website
a read, but one important
thing to note, is that the current
name registrar is temporary.
It’s expected that one
to two years from now, a
permanent registrar will
be deployed with more
improvements and techniques
to prevent squatting.
The current temporary
registrar is to create
community awareness, and
serve as an initial testing
of the concept.
Once the permanent registrar
is deployed, all domains
from the current registrar
will be moved over.
There’s also a certain
set of rules to follow for
ENS domain names, like being at least
seven characters long.
This is also a strategy
to prevent squatters from
getting the value of short
name domains early on.
As the project evolves
and gains awareness in the
community, shorten domain names will
become available for auction.
To register a domain name,
you would first check
whether its even
available, if not, the site
will let you know when
it comes up for renewal.
If it is still available, you
begin a smart contract auction
for the domain by sending
the maximum amount of ether
you’re willing to bid.
The minimum amount for a
bid is currently .01 ether,
which is less than 10 dollars.
The auction lasts for
three days and anyone can
submit a bid, but the bid
is concealed so that no one
can see its value.
Before sending any ether,
make sure your metamask is
unlocked so the website
can detect your account.
After the auction ends, the
two day reveal phase begins,
during which anyone who
submitted a bid, must reveal
the details of their bid.
If you fail to reveal within
those two days, your bid
is lost and the ether is unrecoverable.
If your bid wasn’t the highest
revealed bid, your money
is returned to you, minus a .5% fee.
Whoever reveals the highest
bid by the end of the
reveal phase is the winner,
but they only pay the amount
of the second highest bid.
This gives the winner
rights to the domain name
for at least a year, after
which they can choose to
relinquish it and get
back their locked ether,
or keep the ether locked
to continue owning it.
ENS also allows for subdomains
that can map to different
Ethereum addresses, as well as
transferring ownership of domains.
You could also use the ENS
source code to run your own
private name registry
that serves your own daps.
A current limitation of ENS
domains, is that they are
not supported by popular
web browsers, like Chrome,
which uses DNS, however, work is currently
underway to enable popular
browsers to understand
ENS names without having
to update the browser.
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