iPost Enterprise requires that all clients delegate a domain or subdomain for sending purposes. There are four possible ways to provide a subdomain for use in mailings from iPost.

1. Name service delegation. This is the preferred method because it allows iPost to create and maintain authentication records and IP addresses and shows your brand identity consistently across all steps of the email process. All steps of name service delegation must be completed before any iPost setup is performed to ensure your deployment is as efficient as possible. The subdomain can be any word or letter prepended to your existing domain, such as:
   
   news.[domain].[com]
   mail.[domain].[com]
   email.[domain].[com]
   e.[domain].[com]
   
   
2. Canonical name aliasing (CNAME). Some registrars and other DNS hosts do not allow creation of “NS” (nameserver) records for delegation. In this case a “CNAME” record may be created that points to a second name managed by iPost. This has many of the same benefits of subdomain delegation but, in some cases, may expose the iPost-managed name. To use a CNAME, an iPost client record must first be created, so iPost setup must be interleaved with establishing the CNAME. Please notify your Customer Success Manager if subdomain delegation cannot be done.  It should also be noted, that Google postmaster tools cannot be used with CNAME delegations.
3. Client-hosted name service. In this case, all DNS records are stored at your registrar or DNS provider. THIS IS NOT RECOMMENDED because it means that any future changes iPost may need to make must be communicated through your technical staff, which may result in disruptions to the email services provided to you. To use this approach, iPost must complete all setup and communicate detailed DNS information to your technical team, wait for your DNS service to be updated, and then perform final adjustments and tests. Hourly charges apply for this work. Furthermore, iPost only approves of a client-hosted name service when you have competent technical resources available to assist with the DNS configuration process.
4. New domain registration. In this case, an entirely new domain name is registered, either by you or by iPost, and full control of that domain is assigned to iPost. This is also not recommended because new domains are viewed with some suspicion by ISPs, which may impact your initial deliverability. Furthermore, recipients may perceive the new domain as an attempt by a third party to masquerade as a trusted sender (i.e., a phishing attempt or a source of malware), which may increase spam complaints and reduce response rates.

If you cannot provide a sub­domain, iPost will assign a name that we manage, but this weakens your brand identity and is not recommended. It also has some of the drawbacks of registering a new domain.

Once the delegation is in place, please contact iPost Client Services so iPost can check your configuration and complete the setup.

Before a sub-domain can be delegated, the correct nameserver for the parent domain must be found. In many cases the parent nameserver and the domain registrar are one and the same. Therefore, the registrar’s tools may be used to delegate the sub-domain (see example below). In other cases, the nameserver may be located at a web hosting provider or may be privately operated by your IT department.

We recommend keeping the subdomain name short to keep down the length of the URL in the text version of the mailing; e.g., if the company name is example.com, you might use a subdomain name of news.example.com.

In the event that delegation records cannot be created for technical or policy reasons, the subdomain can be created as a CNAME (canonical name) record instead.

1. Contact your iPost representative and inform them that you wish to create a CNAME.
2. iPost creates a customized name to be the target of your CNAME alias. This name typically has the format yourbusiness.ip02.com or something similar.
3. Your iPost representative will communicate this name to you. Using your registrar control panel (or via your technical staff), create a CNAME record linking your desired sub-domain to the iPost-managed name.
4. Inform your iPost representative that the CNAME has been created. iPost then validates the new sub-domain and completes your setup.

A “sub-domain” usually refers to a name with three or more parts separated by dots (e.g., news.example.com). It is typical to start with the “second-level” domain (example.com) that is best identified with your brand, and then add a third “level” (news) that you designate for email purposes. This is the same pattern by which “www” (world wide web) is often designated for website use, but there is no de facto standard for email akin to “www” for websites.

In some cases, you may wish to create a second-level domain exclusively for email (the new domain registration option described above). The instructions for creating name server records for a second-level domain are similar to those for sub-domains, with one important difference: Name service for a second-level domain CAN NOT be delegated. Instead, iPost’s name servers must be assigned to the second-level domain at the registrar, and you give iPost full control over all third-level (or greater) names within the second-level domain.

We do not recommend using second-level domains in this way, but it is supported.

Name service delegation, or the creation of a CNAME, enables the following:

1. Our system automatically generates a complete set of DNS records for the appropriate domain. That set includes:
   1. A records: Address Record points a domain or subdomain to an IP address.
   2. MX records: Mail eXchanger record is a type of certified and verified resource record in the Domain Name System that specifies a mail server responsible for accepting email messages on behalf of a recipient's domain.
   3. TXT records for:
      1. SPF: Sender Policy Framework record is used to indicate to mail exchanges which hosts are authorized to send mail for a domain.
      2. DKIM: DomainKeys Identified Mail is a protocol that allows verification through cryptographic authentication.
      3. DomainKeys: A deprecated email authentication system designed by Yahoo to verify the domain name of an email sender and the message integrity.
      4. DMARC: Domain-based Message Authentication, Reporting & Conformance is an email authentication, policy, and reporting protocol. It builds on the widely deployed SPF and DKIM protocols, adding linkage to the author (“From:”) domain name, published policies for recipient handling of authentication failures, and reporting from receivers to senders, to improve and monitor protection of the domain from fraudulent email.
   4. For a delegated sub-domain only, a further sub-domain “img” for hosted assets (e.g., img.news.example.com)
2. URLs in the email content are automatically replaced with new URLs that use the sub-domain so that iPost can track views and clicks. Those new URLs redirect to the original URL after recording the action.
3. The SMTP envelope FROM: field uses a tagged address at the sub-domain, so that iPost can handle bounces (via the automatically created MX records) and match them with recipient addresses.
4. At the customers’ option, the user-visible From: field in the message may use an address at the sub-domain (we call this the IBMF, “in-bound message filter”, address) to automatically process opt-out requests, out-of-office responses, etc. (also via the MX records). This is not required. The customer may use any other working email address and handle all responses themselves.

This automation frees you from having to react if we update any of our IP addresses or if a new type of TXT record becomes standard, etc.