Arrow Home  
    Home >
  Frequently Asked VoIP Questions

These Frequently Asked Questions provide quick answers to the VoIP questions you ask the most. The more you ask us, the more information we'll have to share in these online posts.

What DSX VoIP Training Resources are available?
  • There are DSX-specific and general online training courses available. Click here to review the course offerings.

Where can I get general information about implementing VoIP?
  • We offer three white papers: VoIP Requirements Overview, IP Questionnaire, and IP Requirements that should help you. To review these and other VoIP resources, click this link and review the VoIP Readiness links in the table of contents.

How do I know if the remote site is capable of supporting VoIP extensions?
  • Check these VoIP Readiness Test Tools. They will help you quickly determine if the remote site is capable of supporting IP extensions.

What additional DSX hardware and software do I need for DSX to support VoIP?
  • You'll need to purchase and install a VOIPDB in your system for VoIP. Review these installation animations for DSX-40 and DSX-80/160. You'll also need the latest Version 3 System Software and System Administrator, available free on this web site. All other DSX equipment is compatible.

What are gateway ports?
  • A gateway port is a shared resource used to connect IP phones to system ports (stations, lines, voice mail, MOH, etc.). Gateway ports are provided by the VOIPDB. You can only install one VOIPDB per system.
  • An IP phone to IP phone connection currently requires a gateway port for each phone. Peer to peer IP capability doesn't require gateway ports and will be provided in a future release.
  • The VOIPDB comes with 4 ports. License upgrades are available in 4-port increments. A maximum of 16 ports can be licensed on one VOIPDB. The 4-port upgrades are available by software licensing. The DSX-40 supports up to eight gateway ports, regardless of the number licensed. DSX-80/160 supports all 16 gateway ports. Click here for more on the available licenses.

Do the DSX IP keysets have limited feature operation?
  • The DSX IP keysets have the same feature capabilities as their digital counterparts. The features operate identically.

Do I have to use a DSX IP Adapter for each IP keyset?
  • No. However, you will still need to provide power via an 802.3af compliant PoE switch or midspan injector. Please note that the DSX IP Adapter also provides a connection for a local PC via the built-in Ethernet switch in the IP phone.

I have a single network cable to my desk for my PC. How do I connect my IP keyset?
  • You can optionally connect a PC to the PC jack on the DSX IP Adapter. Keep in mind that the telephone must be connected for the PC jack to operate.

Would connecting both the DSX and the remote VoIP telephones to the public internet (with public IP addresses) work without a special router or VPN?
  • Although generally not recommended for security reasons, you can connect both the system and the remote IP telephone directly to the internet if you have two public IP addresses.

Can two DSX systems be linked together (i.e., networked) over IP?
  • No - not at this time.

Will the remote IP telephones require a VPN tunnel to work properly?
  • Without a VPN, the IP telephones will work with compatible SIP-aware routers. For more on this, see NAT Traversal.

Will SIP trunking be supported?
  • Yes. SIP Trunking for DSX is currently in Beta and will be available May 2011.

About every 15 to 30 seconds, the IP keyset beeps 4 or 5 times. What is causing this?

This indicates an RTP alarm condition. This can be caused by insufficient bandwidth (QOS) or a Codec mismatch between your system and the remote IP extension. To check the Codec, please do the following:

  1. In System Programming, check the setting of 2106-01: VoIP Profile. For remote extensions, it should be Profile 2 (which uses CODEC G.729 by default).
  2. At the remote terminal, while on a call:
    • Press CHECK for two seconds, then dial 1.
    • The 2: Codec display selection shows the Codec the telephone is using for the call.
    • Press CLEAR to return to the normal display.
  3. Make sure the entry in 2106-01: VoIP Profile matches what is used by the telephone.







Arrow Site Map
© 2015 NEC Corporation of America.
Search Page