Overview of 3G Cellular Interfaces

Definition

A 3G cellular interface is a physical interface supporting 3G technology, and provides enterprise-level wireless Wide Area Network (WAN) access services.

Purpose

Although wired WAN access technologies, such as optical fibers, xDSL interfaces, and E1/T1 interfaces, are mature and widely used, they become the bottleneck in special scenarios, including:

• For enterprise branches or offshore oil fields located in remote areas, the wire WAN access service is unavailable or costs too much.
• At disaster sites, wires need to be connected quickly and temporarily before the wired WAN access service can be restored.
• The wired WAN cannot provide full coverage for all gas stations and ATMs that are widely distributed.
• Mobile office is required.

In these scenarios, the wired WAN access service cannot meet users' requirements.

The Third Generation Mobile Telecommunications (3G) technology is a cellular mobile communications technology that provides high-speed data transmission. It can transmit voice and data information simultaneously. You can use 3G cellular interfaces to transmit voice, video, and data services, thereby providing wireless WAN access for enterprises.

Limitations

3G cellular interfaces have the following limitations:

• Data connection: Data connections can only be initiated by 3G cellular interfaces but not carrier's devices.
• Throughput: On wireless networks, the throughput changes as the number of online users changes or network congestion occurs.
• Delay: Compared with the wired network, the wireless network may cause longer delays. The delay depends on wireless network technology standards and the quality of the network services provided by carriers.
• Additional restrictions from carriers: Some carriers may require additional restrictions. Before you access a carrier network through 3G cellular interfaces, you must learn the restrictions required by the carrier.