Smart Access Gateway (SAG) supports three network topology scenarios for connecting on-premises networks and remote users to Alibaba Cloud. Choose the topology that matches your deployment scale and connectivity requirements.
Choose a topology
| Scenario | Deployment mode | Redundancy | Best for |
|---|---|---|---|
| Mobile and remote devices | SAG app (software) | Encrypted connections over internet | Office automation, remote O&M |
| Small-scale branch networks | Inline mode | 4G card as standby | Small offices, retail stores |
| Large-scale branch networks | One-arm mode | Broadband + 4G + Express Connect | Large-scale networks |
Connect mobile and remote devices
The SAG app provides dial-up access for personal computers (PCs) and mobile phones. Connections between client devices and Alibaba Cloud private networks are encrypted, making this topology suitable for office automation and remote O&M.
Connect small-scale networks
Deploy SAG devices in inline mode to connect small office branches or stores to Alibaba Cloud.
For redundancy, we recommend that you purchase a 4G card which supports data transmission and insert it into the SAG device. The 4G card operates as a standby connection: if the primary connection fails, it takes over data transmission automatically.
Connect large-scale networks
Deploy SAG devices in one-arm mode to connect large-scale networks to Alibaba Cloud.
For multi-link redundancy, purchase a SIM card and activate Express Connect. This puts the broadband network, 4G network, and Express Connect in active-standby mode, improving overall network reliability.
SAG supports two ways to integrate Express Connect into a large-scale topology:
Express Connect circuit connected to the SAG device
Traffic from the on-premises network is preferentially forwarded over the Express Connect circuit.
Express Connect circuit connected to a local internet-facing device
Configure priorities on the self-managed device for the SAG device and Express Connect circuit based on your business requirements.