I don’t know if auDA provides a checker - this might be a bug in some registrar checker given the rules say business names are allowed?

Anyone doing business under a name other than their legal name in Australia is supposed to register a business name so as not to breach the Business Names Registration Act 2011, and all business types (sole traders, companies, partnerships etc…) can register business names. The same legal entity can have more than one.

I think the question really is whether using a domain name is really the same as doing business as that name. For example, if Joe Bloggs owned flowers.com.au, and visiting the site showed a banner showing Joe Bloggs and underneath it the words Flower Shop, I think it is a reasonable case to say the business is trading as Joe Bloggs, and the Flowers part is identifying the service provided.

That said, Joe Bloggs could remedy the situation easily by registering Joe Bloggs Flowers - the auDA rules allow for registering domains that contain only part of the name (“Match means that the Domain Name being applied for is identical to one, some or all of words or numbers used in the Person’s Legal Name, Business Name or Australian Trade Mark. The Domain Name must use the words or numbers in the same order as they appear in the Person’s Legal Name, Business Name or Australian Trade Mark and must not include any additional words or numbers”). The Business Name registration rules have complex rules about duplicates, so if someone else already registered Joe Bloggs Flowers even though he had flowers.com.au, he could still come up with a different name that included the word Flowers and keep the domain. However, this would require paying to register the business name, and renewing it every year.

So it is creating a small extra expense for business owners that in some cases is probably not legally necessary, just to keep auDA happy.

If you have a VPS with a company that’s not super shady, and you don’t mind jumping through hoops for a few of the bigger providers (Microsoft + Google are the worst) and running around getting off any blocklists once when you start using the IP, it is not actually that hard to host your own.

That said, this advice probably applies more to people who, for example, already know what ssh is and already know or don’t mind learning what DMARC is, for example. Someone who isn’t technical and doesn’t want to become technical probably is better off with paying someone else to host a mailserver for them.

I host my mail server on a VPS.

I suggest making sure you get DMARC / DKIM / SPF working, and having an anti-spam strategy (greylisting helps, but there are a few ASNs that just exist to send spam). Also make sure your IP is not on any public spam list.

The next problem you might face is that Microsoft and especially Google like to make it hard for anyone not using their services. With Microsoft, you fill in a form and jump through some hoops and they’ll start accepting your email enough to land it in spam. Unless you are regularly sending to Microsoft, it is hard to keep them accepting mail, but just sending to a free Hotmail address (owned and occasionally marked as read and deleted by you!) on cron is enough to keep occasional mail deliverable as long as none of your mail ever gets marked as spam. Google can be more of a pain to small email servers in terms of not landing in spam, but I think occasional reports of not spam will help you.

In terms of keeping down spam:

• postgrey or similar for greylisting keeps out the least serious spammers.
• The notorious spammers / bulletproof hosting is best blocked by ASN since they regularly shift IP addresses. Try a script like this on daily cron (assuming you jump to the custom BAD_AS table from your INPUT iptables rule) - please don’t run it too often since routeviews is a free public service and you should be respectful of them:

#!/bin/bash -e

TEMPDIR=$(mktemp -d)
trap 'rm -r "$TEMPDIR"' EXIT

curl https://archive.routeviews.org/oix-route-views/oix-full-snapshot-latest.dat.bz2 -Lo "$TEMPDIR/snapshot.bz2"
bzgrep -e " (15828|213035|400377|399471|210654|46573|211252|62904|135542|132372|36352|209641|7552|36352|12876|53667|138608|150393|60781|138607) i" $TEMPDIR/snapshot.bz2 | cut -d" " -f 3 | sort | uniq > $TEMPDIR/badranges

iptables -N BAD_AS || true
iptables -D INPUT -j BAD_AS || true
iptables -A INPUT -j BAD_AS
iptables -F BAD_AS

for ROUTE in $(cat "$TEMPDIR/badranges"); do
    iptables -A BAD_AS -s $ROUTE -j DROP;
done

• Despite Google being so hostile to very infrequent emails from IPs that have years of never sending spam, just because they are small, Gmail and Firebase are one of the most significant spam sources. I find client-side filtering works best for things like that which get through your other defences.
• Another spam source is Docusign. These types of companies tend to shut down individual scammer / spammer accounts, but then allow them back in for the same scam with another account.

Note that of the spam that gets through if you have the basic defences, it’s probably a similar level to big corporate hosted mail, so don’t let this deter you (I just hate spammers).