They say opinions are like belly buttons, everybody has one. (that’s the “clean” version of the saying). So I’m asking for yours. I hope you see it as a fun exercise.
I’m designing a phone system from the ground up. Will be about 1000-1300
seats mixed 80/20 VoIP/Analog. 58-acre campus environment with 23
buildings. Userbase is emergency services organization, 24/7/365
operation. Down time is not an option, but “blips” are acceptable. Repair time is immediate. We need failover for the failover essentially. However, money is a major factor, so I have to do it all for nothing. So here’s what I’m thinking. Please throw in your 2 cents.
Network will be separate for phones. Fiber infrastructure available between buildings as well as copper. Internet access will be limited to a single administrative console on a temporary basis, and then only when remote 3rd party support is required. Access for 3rd party support will be supervised through remote access tools such as VNC, GoToMeeting, etc… etc… System will have zero access to local data network. This means all ancillary support servers such as DHCP, DNS, NTP, FTP, etc…etc… will be specific to the phone system. Yes, I know some responders at this time will become fixated on me gaining this connectivity. It ain’t gonna happen. It’s not an option. Period, end of story. These are the parameters I must work within. Trying to “fix” that will be a non-starter.
The phone system will upgrade an existing TDM-based system. Mitel SX2000
with NuPoint Voicemail. This will not be a dump-trunk replacement. I
expect at least a one to two-year transition, meaning we will have time to find problems, work bugs, and learn over time, with minimized impacts. It also means we’ll be supporting two systems for some time.
PBX is 97% serving your basic phone on the desk. Nothing special. Customers expect the usual list of features. There will be a goodly number of hints required for BLF on maybe 150 phones. There is one office of about 30 phones in a call-center environment that will need that service. They would be considered low volume (but don’t tell them that).
My Skills… I am not a Linux kung fu master, but I have built and managed my share of Linux servers on mutiple Linux flavors. I am a DCAA, having been through formal training, and have been playing with Asterisk for years, but always in fits and spurts and never in a live environment so I am by no means a kung fu master there either. I have started dabbling with virtualizations via XEN, but I am not comfortable enough with it to go live this first round. I can see myself implementing it in about three years once we’re totally comfortable with what we have, so I
can then have time to get that skill sorted. I was a network engineer for the US no3. telecom for a number of years, 10-years in comm-electronics in the military before that. Telecom my entire career. I’ve got the kung-fu to handle the network side of the house, and having administrated multiple PBXs for decade-plus, I’ve got the concepts down.
No plans to build databases for things like directories, etc… I’m not greatly confident in those skills, and to date, haven’t found anything that really stands out that would make me require that. You may think otherwise, so please chime in. I say that, but at the same time I
recognize I may require a GUI interface once fully deployed to allow lower-skilled people to follow the motions to complete simple moves, adds, and changes. I’m fighting the uphill battle that is the “GUI is new, CLI is old” mentality.
System will use G.722 for VoIP Phones.
So there’s the groundwork. Here’s the hardware plan.
Plan is to build my own servers following industry standards (ATX) and using industry standard equipment. Why? Spares? Whether redundant or not, I will still have spares for the most common elements on the shelf so equipment can be returned to service as quickly as possible. This will also allow me to be comfortable with more “basic server”
configurations and help keep cost down. For example, Servers with single power supplies vs. dual. Also, components will be standardized for all equipment to aid in supply requirements.
First the layout.
2-servers acting as gateways. Each handling 2 PRIs for outside trunks. They’ll also handle the analog ports. Failover will be in the form of degraded trunk access if one should fail, but the second will be able to support services in degraded fashion.
2-servers acting as VoIP PBX. A primary and a spare. Meaning one will be capable of handling the load of the entire system, and the other will pickup when the other dies, an active/passive cluster. Will also take care of voicemail. Use of heartbeat, pacemaker, etc… etc…
2-servers for support services. DNS, DHCP, FTP, NTP, etc… etc…Basically, everything the phones need to run plus system monitoring via something like Nagios.
1-Desktop for administration of everything. Provided from corporate. Basic Desktop.
Looking at Intel Xeon E3-1230 ivy-bridge processors. 8GB DDR 1333 for Gateways and 16GB for PBX and support servers. 1TB drives in RAID 10 via LSI 3ware 9650 cards for PBX, 250GB for Gateways. Supermicro X9SCM-F mobo.
OS of choice is Debian. Primarily because it appears to have the best availability for non-Internet installations.
Now the Infrastructure
2-network switches in the phone room. Each set of “primary” servers to one, and “secondary” servers to the other, and each switch connected to the other. Each switch will have a different path to the network. RTSP
implemented for dual path to the campus. Only one location on campus will have or require dual paths to the network.
Most buildings on campus have cat-3 for voice installed in the mid-90s. Wired at the same time as the data network, I can generally conclude they’re the same length. It’s terminated to 110-blocks on walls. Some cabling is only 2-pair. I know I will find surprises. Essentially, I
plan to re-use this cable, knowing in some circumstances I will need to make special patch cables. These connections will be forced to 10BaseT
at the switch.
I require PoE to the wire closets, no power sourced at the desktop. I
require a minimum eight-hours emergency power which will be in the form of UPS in most cases. Why so much backup? Well if you ask, we can start a new discussion about NEBS compliance, E911 Federal, local, and state requirements, etc… etc…
So why not use existing data network? The current data network consists primarily of 10+ year-old 100BaseT switches, no PoE. Barely any backup power. I don’t believe they’re using QoS. The network office is a separate department from the phone office. I question their skills, and above all, network folks treat phones like computers, not like multi-million dollar lawsuits when they don’t work in an emergency. We could make another thread out of this huh? To use existing data network would require hundreds of thousands in Cisco 6500 and 4500 series switches. Network has already stated they’d want phone on separate ports from computer, and I agree. (Yet another thread). Thousands of computers across 23 buildings, and it must be Cisco by corporate policy, where phone is a different animal that doesn’t have this limitation. You can see we’re talking hundreds of thousands in just switching gear. Then UPS
requirements to support a big hog of a switch vs a teeny 48-porter w/PoE, and you just cranked up one-time and long term cost for that as well. Trying to replace the network to support the phones is cost prohibitive and a non-starter. Maybe we can talk about it in 5 years once they’ve replaced everything.
I plan to purchase lower-cost Layer-2 smart switches from vendors such as DLink, Xyxel, Dell, etc… Many players in the market for 48-port switches with PoE and multiple SFP.
I think that’s probably enough… I apologize for the large email but I
couldn’t think of a better way to get a qualified peer opinion without laying out the facts.
Thanks in advance for your review and consideration…!!!