IoT receives much industry and economic focus because of the number of devices that will be eventually be deployed and the amount of data these devices will produce. There are two methods regarding how IoT will take form:

• Edge-level sensors and devices will provide a direct path to the cloud. This implies that these edge-level nodes and sensors will have enough resources, hardware, software, and service-level agreements to transmit data across the WAN directly.
• Edge-level sensors will form aggregations and clusters around gateways and routers to provide staging areas, protocol conversions, and edge/fog processing abilities, and will manage security and authentication between the sensors and the WAN.

The first model is difficult and costly for power and cost-constrained edge-level sensors/actuators/devices. A more logical form will be the latter case. The role of a router or gateway at the edge of sensors/devices includes the formal networking abilities modern routers provide, such as link routing, port forwarding, tunneling, security, and provisioning. Principles of TCP/IP routing and bridging are provided in a plethora of literature and are too broad to study here. This chapter explores the role and necessity for edge-level routers and provides tips and recommendations as to the features to consider when deploying a mass IoT solution.