The listed equipment has been tested and approved for integration into X-on systems. Consequently this equipment is currently supported by X-on1.

  • Basic Handset: Cisco SPA 303 (previous Linksys SPA922 and similar), Snom 300
  • Handset with Directory: Snom 370, Cisco 79402, Cisco 79423
  • Conference Phone (Handset): Polycom Soundstation IP 5000 Conference VoIP Phone
  • Included with Surgery Connect: Yealink T21P, T27P, T31G Handsets, Yealink YHS33 Headset

1 Within the parameters defined by integration with our system i.e. some extended features of the equipment may not be available via our system. Available features are fully supported.
2 Cisco 7942 requires configuration of firewalls to handle port forwarding and allowance for this should be made.3 Cisco 79** phones must be upgraded to SIP firmware. UCCP (Skinny) protocol is not supported.

Given the wide array of client requirements and existing in-house systems, further clarification should be obtained from your Account Manager.

Compatible Equipment

From a technical perspective the following equipment may integrate successfully, given the known parameters. Customers have used this equipment successfully on X-on services. However, we cannot guarantee full compatibility, and consequently are unable to guarantee support for this equipment. Configuration support for the following will not be included in your contract unless explicitly detailed and will be chargeable at agreed rates.

Standalone Phones (Hardphones)

  • Aastra SIP phones
  • Cisco 7900 series phones with SIP Firmware (other than those listed above)
  • Gigaset (formerly Siemens) SIP phones
  • Grandstream SIP phones
  • Sipura/Linksys/Cisco ‘SPA’ Phones
  • SNOM phones (other than those listed above)
  • Yealink SIP phones


  • SNOM MM3 monaural headset (for SNOM 300)
  • SNOM MM2 monaural headset (for SNOM 370)
  • Plantronics M175 (For Cisco SPA303)


  • Bria
  • EyeBeam
  • SJ Phone
  • X-lite

PBX Software (for clients with X-on SIP Trunks)

  • Asterisk
  • FreePBX
  • FreeSwitch
  • OpenSER / Kamilio
  • OpenSIPS
  • SER

Smartphone Software

  • Android Gingerbread integrated SIP functionality
  • Sipdroid
  • iPhone App ‘Acrobits’

VoIP Connectivity Requirements

Due to the number of outside factors affecting VoIP Telephony and the problems resulting from less than ideal configurations, X-on require the following VoIP connectivity conditions to be met:

  • Dedicated ADSL lines for voice calls are required for VoIP clients using ADSL broadband. There should be no sharing of data traffic. BT ADSL Max is a recommended minimum.
  • Only X-on approved routers can be used.
  • Only X-on approved handsets are to be used – see the list above.
  • Softphones are not suitable for business communications.
  • In the event of a reduction in call quality we require sufficient backup to landlines or mobiles.

X-on uses Tier 1 VoIP routes with the added safety of PSTN backup. Coupled with an approved client VoIP configuration ensures we maintain the highest possible standards of VoIP call quality.

For more information please call Sales on 0333 332 0000.