A typical small branch office, usually with fewer than 25 users, often requires simplified, efficient networking solutions. One of the common needs is to reduce infrastructure complexity while still supporting essential services such as routing, firewalling, switching, and voice.
Cisco documents related to branch infrastructure design state that for small branches, integrated services routers (like ISR 1000/4000 series) are recommended because they combine multiple services—such as WAN connectivity, security (firewall/IPS), VPN, wireless LAN controller functionality, and voice support—into a single platform. This reduces hardware footprint, simplifies management, and ensures better performance at the edge.
Therefore, integrating multiple network functions into a single device fulfills a typical requirement of a small branch, making option A the most accurate.
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