Which statement describes the one-arm deployment mode?

• A. It uses two interfaces
• B. It uses a single interface
• C. It is always transparent
• D. It is a forward-proxy only mode

Answer: (B)

One-arm deployment mode uses a single interface to handle both client and server traffic. In this setup, the Citrix ADC sits in the same network segment as the clients and backend servers, and a virtual IP on that single interface receives client requests. The appliance then forwards those requests to the appropriate servers and returns the responses back out through the same interface, often using SNAT so servers see the ADC as the client. This topology avoids needing a second NIC or a separate in/out path between clients and servers, which is why it’s described as using one interface.

This differs from setups with two interfaces, which are the inline or two-arm deployments that physically separate the client and server paths. It’s not guaranteed to be transparent, since one-arm deployments can be configured in non-transparent ways using routing and NAT. And it isn’t limited to forward-proxy functionality; a one-arm ADC can perform load balancing and reverse-proxy duties as well, not just forward proxy.