Time to Drive Solo? Or Stick With the Carpool?


CarpoolIf you have ever dealt with onboarding at an ESP, you probably know one of the main topics of discussion around scalability and reputation is whether to go with dedicated or shared (pooled) IPs.  Are you ready to “drive solo” with a dedicated IP, or do you stick with the “carpool,” an IP pool.  It can be daunting and sometimes a bit ambiguous as to which model fits your needs best.  With that in mind, here are the top 5 factors you need to keep in mind when determining which path to go down.

1. How much mail are you planning to send?
The way email is relayed from sender to receiver is fundamentally based on the IPs (or network fingerprints) involved in the handoff.  The more IPs you have, the more inroads you can create with getting mail delivered to an ISP (such as Yahoo!, Gmail, etc.).  Many ISPs have hard requirements around how many messages will be allowed through and how many active IPs you can use at one time.  If you’re looking at sending more than 20,000 per week, you should see if having your own IPs to send through will give you the scalability needed to match that.  However, if you’re not going to be sending at least that much, you might have more horsepower than you need which is where a pooled group of IPs helps – it spreads the load like peanut butter over the different IPs from the grouped senders.

2. What is the deliverability impact?
Email deliverability, at least right now, is heavily weighted on IP reputation.  What does this mean?  Like a credit report, ISPs will determine what sort of mail they can expect from an IP based on the history of mail that’s been coming from it.  If you have mail that is strong enough reputation wise, which includes low bounce rates and end recipient complaints, a dedicated IP might work.  You will only have to worry about your own mail’s impact as opposed to allowing the possibility of other mail going out the same IPs impacting your delivery.  But, proceed at your own risk – when using a dedicated IP, you determine your own fate.  Pooled IP senders usually rise and fall with each other depending on the sum total of mail being sent out where one particular sender won’t necessarily sway the pool as a whole.  This is why choosing an ESP that has good deliverability rates on a pool is of paramount importance – you’ll be judged by your peers.  A bad reputation will cost you in the long run.

3. How is dedicated v. pooled different in implementation?
Typically, a new IP will be warmed up (or pulled from an already warm pool) and allocated to a sender on a dedicated system.  This means special attention should be given to initial sending and ISP feedback.  Dedicated IPs also require a bit of inflight tweaking as the ISPs learn what sort of mail will be delivered.  But, once this initial ramping has completed, you’re free to do as you like as long as you don’t violate any ESP best practices.  You also have more wiggle room for making your IP specific to you since you’re the only one it’s representing.  Pooled IPs generally don’t require much technical implementation since the sending IPs are ready to go and have a critical mass of mail already being sent out.  However, the business investment with vetting and passing certain ESP requirements can be heavy since the new sender has to prove they won’t do anything to risk the pool’s reputation and thus the existing senders using it.

4. Does the cost make sense?
Dedicated IPs require more time, effort and maintenance to get everything setup.  They use their own bandwidth which subsequently means the cost isn’t shared.  Most ESPs charge for this as a result.  Pooled IPs?  There’s usually no cost associated above and beyond the normal sending charges.  This means money saved for smaller sender.

5. How much autonomy do I want?
This is a critical question for anyone sending email.  Do you care if your messages go out with custom or group headers?  Do you want to be able to send on your own schedule whenever you want (again, as long as you stay within the ESP’s published best practices)?  How about not having to worry about what other senders in the same pool are doing?  With dedicated IPs, you get to be in control of a lot more of the decisions around how email is actually delivered.  Many clients don’t care, though, as email is just a component of a much larger marketing strategy and as such, they don’t have the resources or capitol to afford dedicated IPs.  In a pool, you’re more heavily scrutinized depending on any hiccups along the way impacting the greater good.

There’s a tendency for email marketers to see the issue as black or white wherein they fall into one or the other side with strong convictions.  It’s not that simple and as email becomes more widely adopted as a marketing and end customer communication vehicle, taking into account the above points will help you achieve success no matter where you land.

– Chris Wheeler, Director of Deliverability, Bronto

Chris is leading the charge to ensure both Bronto’s customers and staff are well-informed about email marketing practices and technology as well as being the face of Bronto deliverability externally.  Previously, he created the internal deliverability program at Amazon.com alongside program managing the operations of the email team and was at an ESP leading a team of deliverability consultants.  Besides being a frequent contributor on Deliverability.com, Chris is a part of many email industry forums, both business and technical.