Making Calls using IP Addresses

Note: The multi-functional buttons will function as LINE keys when all LINEs are busy. The LED will flash in red to indicate an incoming call. Press the button to pick up the call. If any one of the Multi Purpose Keys is associated with a call, the button’s speed dial/BLF function will not work.

Direct IP calling allows two phones to talk to each other in an ad hoc fashion without a SIP proxy. VoIP calls can be made between two phones if:

•Both phones have public IP addresses, or

•Both phones are on a same LAN/VPN using private or public IP addresses, or

•Both phones can be connected through a router using public or private IP addresses (with necessary port forwarding or DMZ)

To make a direct IP call, please follow these steps:

1.Press MENU button to bring up MAIN MENU.

2.Select “Direct IP Call” using the arrow-keys.

3.Press OK to select.

4.Input the 12-digit target IP address. (Please see example below).

5.Press OK key to initiate call.

To make a quick IP call, please see next section.

For example: If the target IP address is 192.168.1.60 and the port is 5062 (e.g. 192.168.1.60:5062), input

the following: 192*168*1*60#5062 - The “ * ” key represent the dot“.” ; The “#” key represent colon “:”. Press OK to dial out.

Quick IP Call Mode

The GXP also supports Quick IP call mode. This enables the phone to make direct IP-calls, using only the last few digits (last octet) of the target phone’s IP-number.

This is possible only if both phones are in under the same LAN/VPN. This simulates a PBX function using the CMSA/CD without a SIP server. Controlled static IP usage is recommended.

Setting up the phone to make Quick IP calls

To enable Quick IP calls, the phone has to be setup first. This is done through the web-setup function. In the “Advanced Settings” page, set the "Use Quick IP-call mode to YES. When #xxx is dialed, where x is 0-9 and

xxx<=255, a direct IP call to aaa.bbb.ccc.XXX is completed. “aaa.bbb.ccc” is from the local IP address regardless of subnet mask. The numbers #xx or #x are also valid. The leading 0 is not required (but OK).

For example:

192.168.0.2 calling 192.168.0.3 -- dial #3 follow by SEND or # 192.168.0.2 calling 192.168.0.23 -- dial #23 follow by SEND or # 192.168.0.2 calling 192.168.0.123 -- dial #123 follow by SEND or # 192.168.0.2: dial #3 and #03 and #003 results in the same call -- call 192.168.0.3

NOTE: If you have a SIP Server configured, a Direct IP-IP still works. If you are using STUN, the Direct IP- IP call will also use STUN. Configure the “Use Random Port” to “NO” when completing Direct IP calls.

Grandstream Networks, Inc.	GXP User Manual	Page 17 of 38
	Firmware 1.1.6.44	Last Updated: 12/2008

GXP-280 specifications

The Grandstream Networks GXP-280 is a well-regarded model in the realm of VoIP (Voice over Internet Protocol) telephony, designed particularly for small to medium-sized businesses. This feature-rich IP phone is recognized for its reliability, ease of use, and versatile functionalities, making it a preferred choice among business users seeking a robust and effective communication solution.

One of the standout features of the GXP-280 is its support for up to four SIP accounts, enabling users to manage multiple lines simultaneously. This is particularly beneficial for businesses that require efficient call handling across different departments or clients. The phone sports an intuitive LCD display that provides clear visibility of caller information, call status, and feature access, ensuring user-friendly operation.

The GXP-280 is powered by advanced technologies such as HD Voice, which provides crystal-clear audio quality during calls. This clarity is further enhanced by the phone’s wideband audio support, allowing for richer sound reproduction that is crucial for effective communication. The phone is equipped with dual Ethernet ports, one of which supports Power over Ethernet (PoE), simplifying the installation process by allowing power and data to be transmitted through a single cable.

In terms of flexibility and personalization, the GXP-280 comes with programmable soft keys, allowing users to customize their interface to suit their specific workflow preferences. Additionally, the phone includes built-in Bluetooth support, which extends its capabilities to integrate with wireless headsets, enabling hands-free operations.

Security is also a pivotal aspect of the GXP-280, as it features encrypted signaling and media, ensuring that business communications remain secure from potential threats. The device supports standard security protocols such as SRTP and TLS, making it compliant with contemporary security standards.

Moreover, the GXP-280 offers a variety of codec options, including G.722, G.711, and G.729, allowing it to adapt to various network conditions and requirements. Its compatibility with a wide range of SIP platforms adds to its appeal, making deployment in existing infrastructures seamless.

To summarize, the Grandstream Networks GXP-280 is a versatile, reliable, and feature-rich IP phone that stands out for its clarity, flexibility, and security, making it an excellent choice for businesses looking to enhance their communication systems. With its impressive array of functionalities and support for modern technologies, the GXP-280 is a representation of Grandstream's commitment to providing high-quality communication solutions.