In one of my last posts - What's on your voice readiness checklist!? - We all discussed things to watch out when deploying VoIP. I must say it was a great discussion and many of you brought up some great points! I took some time to consolidate those ideas and put them in a single document. Big thanks to every one who contributed to the discussion and brought up these great points!
Power - How do you plan on powering VoIP equipment (Hand held phones, conference phones, desktop phones, etc), sure you can use power bricks or you can rely on PoE (Power over Ethernet) switches this way you don't have to worry about the additional overhead of the power bricks (ordering, inventory, cost, shipping, etc). You may also have to consider the power budget of those switches, depending on what (if any) other PoE capable devices are already receiving power. Remember many wireless-N & AC access points require more power than the older 802.3af standard could provide to fully operate, or perhaps you also have PoE capable surveillance systems? If you are deploying wireless handheld phones do you need some larger multi-device charging docks, or should you account for spare batteries?
Guides for the end users - This may sound trivial but we can't forget about the end users. Making sure the users know how to access their voice mail and use the IP Phones the way they need ensures we get fewer questions from the end users, which makes everyone's life easier.
QoS (Quality of Service) – This is definitely a very important aspect in every VoIP network. Without QoS to protect the signaling and RTP audio streams from the rest of the IP data network traffic the VoIP system could be rendered completely un-usable. Where should you create your trust boundary and how should you allocate your queue's?
IP Addressing/VLAN Assignment - Depending on the size of your deployment, you might have to take some extra care into your address assignments and DHCP scope creations (Do you need to create any special DHCP Options?). What if your routing schema is summarizable and hierarchical to the core of your network how can you maintain that standardization?
Authentication/Security - How are the IP Phones going to authenticate to the network will you need to deploy certificates or require the phones to participate in Dot1X authentication? Do you need to consider security compliancy with any governing bodies? (PCI, HIPPA, CJIS, SOX, etc)
Site Surveys - More aimed toward VoWLAN (Voice over Wireless LAN) deployments. The RF spectrum is the layer-1 medium for wireless networks, performing a site survey & knowing the RF environment of your WLAN gives you an amazing advantage from a support and maintenance perspective. If you are aware of the extent of your coverage and what interferes are in your environment you can either eliminate those obstacles or work around them eliminating issues before they even arise.
Know your devices - Before heading into a deployment you need to know what devices and how many devices will be affected.
- Is there a standard number of phones per location?
- Do you have to consider fax machines or is IP Fax part of the deployment?
- Where are all the existing phones & faxes located? Over time it is more than likely that a few older analog phones got installed in less than an ideal location far away from the typically users & desktops, perhaps in a storage room or back corner of a warehouse.
Communication Plan - We all know how the users are, they will call into the help desk if the graphic changes on their favorite desktop icon. Just imagine their surprise when their trusty old phone gets replaced with a fancy new IP Phone, possibly with LED flashing displays. Making the sure that the users know when the phone upgrade is going to happen & what to expect post-deployment ensuring they are trained properly on how to use the phones can alleviate a lot of confusion before it even starts.
Active Directory - But wait we are probably network guys, why should we be curious about Active Directory? Well, most major VoIP deployments will most likely involve getting married to Active Directory (or whatever LDAP directory service you happen to be running). This involves populating/synchronizing the user information into the new VoIP system, eliminating the need for you to possibly create all the users manually:
- Phone Number
Budget - How much are you allowed to spend for your deployment? Depending on how large you budget is depends on how much you are allowed to buy, therefore you need to make sure you choose the appropriate IP Phones to fit your budget, make sure you have enough switch ports and/or buy a suitable amount of switches if need be, and how much needs to be set aside for additional cable runs. What about hiring additional help during the deployment? Working with the budget can very tedious and nit-picky it might be worthwhile to get someone from finance depending on the size of your budget.
Training - And no I am not talking about the end users this time! VoIP can be quite the animal and it introduces a wide array of new issues into an existing environment. Making sure the currently IT staff is ready to tackle these new issues will ensure the users are confident when dealing with the IT Staff:
- Help Desk - Making sure the Help Desk routes tickets properly and gets the appropriate information during the initial trouble call.
- Desktop / Tech Support - Making sure the desktop team is familiar with new hardware and can maneuver their way around any new features, basic setup, & can walk the users through any common issues
- Network/Telecom Team - The core teams behind the VoIP/Telecom infrastructure must feel very comfortable with the support & deployment of these types of deployments. After all a business without working phones is anything but. It is also a good idea to make sure these two teams are communicating successfully (if they are separate teams).
Monitoring - Monitoring is usually an after though, but if you setup your monitoring infrastructure during your pilot or initially deployment you alleviate a lot of stress of your teams. Ensuring a proper monitoring solution will provide you with ease of mind that the implementation was successful (at each stage). While at the same time keeping track of your implementation/deployment if you can properly report off your monitoring system.
Dial Plan - Knowing you existing dial-plan and planning for additions to your dial plan is very important, to me the dial plan is like your IP Address Scheme & your routing design.(You can tell I initially came from the IP side and not the Telecom side now :-) ) It is important to ensure calls get routed as designed and you do not assign already existing DN's to another user. Documentation is key!
Devices in the call flow path - As we know VoIP deployments aren't as simply as hey look! 'I got IP Phone, a PoE switch, & a voice capable router... I'm all done!' Some of us might have to account for other devices:
- Firewalls - Firewalls are awesome they protect our network and never interfere with production traffic right, well not always there are a few things we might have to double check. Does the firewall allow RTP streams? How strict is the application inspection? Are you utilizing any non-RFC defined protocols/features the firewall might drop? Do we need to reach another team (security) in preparation for this deployment?
- Gatekeepers & Gateways - Do we have any Gatekeepers or Voice Gateways in our environment? If so who manages them and are they ready for the upcoming changes?