The global SMS ecosystem consists of a separate, logical, or A2P connectivity network – one where mobile network operators (MNOs) have approved, and in many cases, monetized, this type of mostly commercial and non-human-generated traffic. Traditionally, the A2P network uses separate connectivity from the general conversational or person-to-person (or P2P) connections. The reasons for this are numerous; however, a significant reason is that it helps to control spam and “grey route traffic” over the P2P networks.
What do I mean by grey route traffic? Grey route traffic is typically A2P SMS traffic that attempts delivery outside of approved A2P connections or routes into the MNOs. Grey route traffic tries to leverage the P2P network and ubiquitous connectivity to avoid MNO fees or approval processes. Much of it attempts to take advantage of MNOs, aggregators, and even senders. As the ability to reach consumers through SMS is immensely valuable, there are numerous messaging aggregators and service providers that use a variety of tactics to attempt to circumvent MNO-supported routing standards.