I’m at Enterprise Connect 2015 this week in Orlando. My first session was called “Become a SIP savvy Enterprise” by Graham Francis. He talked about what is SIP, why you would use it and the journey your company will need to take to implement it. What I got from this session is a SIP Trunking checklist of questions you need to ask at each step of the way to help plan your SIP implementation. So below is a SIP Trunking checklist of questions you should consider asking, It is complied from the information gained during the session and my experience from customer implementations.
The stages in the list are arranged from the centre of your network going outward. They might not be in logical order for your journey. Also not all questions will be relevant to your implementation and they are mainly from a technical perspective. Need more information about SIP Trunking, check out this post: Sip Trunking 101 – The What and How of SIP Trunking
The SIP Trunking checklist
Stage 1 : Your network
- Are Voice and Data on separate VLANs?
- Is QoS set up on your LAN?
- Do you have monitoring tools for your LAN’s performance?
- Do you have POE capacity?
- Do you have Cat5e or higher?
- Are you going wireless VOIP?
- Will your WAN be used for voice?
- Does it have the capacity?
- Does the WAN provider provide QoS on your WAN?
Stage 2: The Edge of your network
- Over The Top or Assured? (so over the internet or over a service providers line)
- If Assured – Dedicated line or Converged? (A line just for sip trunking or share it with your data).
- SIP trunks direct in to your WAN?
- Centralised or distributed?
(typically after you pick a service provider)
- NAT + port translation
- Encryption – signalling and or RTP
- Coded translation
- Protocol translation
- DTMF support.
- PRI/Qsig connectivity
- Remote user Support
- Web RTC Support
- Monitoring and stats
Stage 3: The Trunks
A very helpful link. http://www.erlang.com/calculator/. Also this step may need to be done at the same as stage 4
- Number of trunks?
- Which Codecs?
- Bandwidth requirements?
- QoS options?
- NAT – Far end or Near end? (who will be doing the NATing, you or the service provider?)
Stage 4: The Service Provider
- Cost – installation and monthly
- DTMF support
- Number Porting?
- Emergency Services?
- Support options?
- Suitable network infrastructure
- Suitable connectivity to your locations
- Codecs supported and future options
- Security options
- Flexibility of provisioning – e.g the ability to bust over your number of trunks
- DR options
- Redundancy options
- Additional features – video, faxing etc.
- SIP Forum – Sip Connect Compliant
- Support with your equipment?
- Small Vs Large provider – Small companies are typically the first adopters of SIP trunks and have survived and along the way gained a lot of experience. Large are slower to join the SIP party, less experience (sometime less features) but has a trusted name and lots of resources.
- Offers a free trial?
This may seem a lot of questions in this SIP Trunking checklist of questions. But typically you can wipe out sections of it. For instance using ShoreTel with the Gamma service provider and an Ingate SBC you can cut out a lot of the testing stage/questions and some of the SBC functionality (for example codec translation, NAT etc) as all three have been certified to work with each other.
Any questions or additions please leave me a comment.