| What hardware is compatible with Callcentric? |
 |
In general most SIP/2.0 hardware should be compatible with Callcentric. As a BYOD (Bring Your Own Device) provider we do not restrict you to using only the hardware we're comfortable with. Users have had success using software from companies such as:
Cisco, Grandstream, Sipura, Linksys, OBiHai, Snom, AVM, DrayTek, Epygi, Polycom, Gigaset, Panasonic, CloudTC, Nokia, iPhone, Android, Avaya, Aastra, Yealink and many more.
Hardware from other vendors surpporting SIP/2.0 should be compatible.
You can view a list of the hardware we have created setup guides for below:
ATA Adaptors
IP Phones
Cordless DECT IP Phones
Mobile Softphones
If you have questions about other hardware please contact us. |
| RETURN TO TOP |
| Can I use the Callcentric service when I travel? |
|
Yes. Using either the Callcentric software on your computer, or an analog telephone adapter such as the Grandstream. Please be aware that the place you are traveling to must support the minimum requirements to use the service.
Please also note that in some countries using VoIP services like Callcentric may be illegal. It is your responsibility to determine whether using the Callcentric service complies with local laws. |
| RETURN TO TOP |
| What software is compatible with Callcentric? |
|
In general most SIP/2.0 software should be compatible with Callcentric. As a BYOD (Bring Your Own Device) provider we do not restrict you to using only the software we're comfortable with. Users have had success using software from companies such as:
3CX, NCH, Digium Asterisk, Counterpath, Acrobits, Snom, Twinkle, freePBX, Android, Nokia Symbian, LinPhone, fring and many other open source and proprietary applications.
You can view a list of the software we have created setup guides for below:
Desktop Softphones
Mobile Softphones
IP PBX Software
If you have questions about other software please contact us. |
| RETURN TO TOP |
| Can I use my hardware/software with your service? |
|
Yes assuming that we support it. Many devices are currently supported and in general you can use any device that supports at least the following:
- SIP 2.0
- RTP over UDP
- DIGEST MD5 authentication
- Fixed Outbound Proxy
- DNS SRV
- G.711 and/or G.729
If after reviewing the supported equipment list you are still unsure if your device will work, please contact us. |
| RETURN TO TOP |
| What voice codecs does Callcentric support? |
|
For calls from one Callcentric user to another any codec can be used.
For calls to the voicemail system and for error prompting the following codec's can be used:
G.711 u-law
G.711 A-law
G.729A
For calls to the PSTN (traditional landline and mobile phones) the following codec's can be used:
G.711 u-law
G.711 A-law
G.729A
For calls from the PSTN to your Real Phone Number the following codec's will be used:
G.711 u-law
G.729A
We recommend that you configure your user agent's codec selection in the following order (with 1 being the highest priority, and 3 the lowest), assuming your user agent supports each of the following. If your user agent doesn't support all of these codec's, just skip the ones that it does not have.
1 - G.711 u-law
2 - G.711 A-law
3 - G.729
All other codecs should be disabled for compatibility reasons. If you do enable codecs which are not listed above then keep in mind that this will only work with calls on the Callcentric network or to SIP URIs. If you wish to configure other codecs then the following order may be considered:
4 - G.722 48Kbps
5 - G.722 56Kbps
6 - G.722 64Kbps
7 - Speex 8Kbps
8 - Speex 16Kbps
9 - Speex 32Kbps
10 - G.726 16Kbps
11 - G.726 24Kbps
12 - G.726 32Kbps
13 - G.728
14 - iLBC |
| RETURN TO TOP |
| Will Callcentric work over my satellite Internet connection? |
|
While it is technically possible for the Callcentric service to work over a Internet connection via satellite, we do not recommend that you use the Callcentric service in this way.
With a satellite connection you will experience high latency (delay) in your conversations, and may experience echo or dropouts in the voice.
Callcentric will not officially support users that are using the Callcentric service over a satellite based Internet connection. |
| RETURN TO TOP |
| Can I use the Callcentric service with a dialup modem? |
|
Yes, you can use the Callcentric service with a dialup modem of 28.8 kbps or faster. However, in general you will find the Callcentric service to be less reliable and you may experience quality problems with calls on a dialup connection. We strongly recommend that you use the Callcentric service on broadband Internet connection such as ISDN BRI, DSL, Cable, T1, E1, Wi-Fi, Wi-Max, etc.
In order to use the Callcentric service with a modem connected to your computer, you will need user agent software that supports the G.729 codec. For more information on software user agents such as X-Lite and X-Pro, please visit the support area to see compatible software. |
| RETURN TO TOP |
| Does Callcentric support DTMF? |
|
Yes Callcentric does support DTMF.
We support both In-Band DTMF and Out of Band signaling through the industry standard RFC2833 specification.
We recommend sending DTMF through the RFC2833 standard since it provides a more reliable way of transmitting DTMF signals compared to In-Band where compression, especially with highly compressed codecs such as G.729, in combination with poor connection quality can distort DTMF signals and make them unrecognizable.
If you choose to use the In-Band DTMF signaling method and experience problems with sending DTMF tones you can try to solve this by choosing G.711 as your preferred/default codec. This way your signals will be sent but won't be as compressed as when they are sent with G.729, or more highly compressed codecs.
If you are not able to choose RFC2833 standard as your DTMF type in your device, you may also be able to select AVT which is the name used for RFC2833 on some devices. You may also try setting your DTMF signaling type to Auto; this will allow your UA to choose the most suitable signaling type.
Callcentric does not support SIP-Info at this time as a method of transporting DTMF signals.
Here is a short list which explains Callcentric DTMF support for SIP communications:
1 - In-Band: Requires a stable connection and works best with a less compressed codec such as G.711. An unstable connection can still affect DTMF signaling however.
2 - RFC2833/Out of band: Works with any codec, as long as your connection does not suffer from high packet loss/ poor quality
3 - SIP-Info: Not supported at this time
If you still aren't able to send DTMF tones you may open a trouble ticket by logging into your account to contact us. |
| RETURN TO TOP |
| Are there any special considerations when using Fring? |
|
Yes. We've seen an issue in Fring's software (at least version 4.0.0.9) that causes Fring to be unable to register (connect) to our network due to how it responds and sends SIP messages. We are attempting to get this resolved with Fring directly, however as a workaround you can do the following which should resolve this issue:
When configuring Fring to use Callcentric, instead of entering "callcentric.com" within the Proxy field, instead enter "fring.callcentric.com".
Using "fring.callcentric.com" as the Proxy should allow Fring to connect to our network and place and receive calls. |
| RETURN TO TOP |
| What video codecs does Callcentric support? |
|
Video codec support on the Callcentric network is supported entirely as a pass through option, as in we do not interfere or transcode video codecs. Support for video entirely dependent on the UA involved in the calls.
Before reading further please be ware that we do not provide support for video calling to or from PSTN numbers. We will not investigate such scenarios if presented and will inform users of this ability not being supported.
Support for video over SIP is very dependent on two factors:- Codec support between UA
- Bandwidth available for calls
If you are using software with video codec support then the codec used must be available on the called end. If you are still unable to establish video data then we can attempt to assist you, however limited our assistance may be.
For reference below are some of the more popular video codecs used:
H.261
H.263
H.263+
H.264
Some devices may also support other less known video codes such as:
Theora
x264
You will want to disable any unused codecs for compatibility reasons as some codecs may affect call establishment. Ideally choosing a single video codec should be the best option.
Please keep in mind that the support for video calls mentioned above is highly dependent on your internet connection and UA. If you have problems you may contact us for further assistance. |
| RETURN TO TOP |
|
