K-Net VoIP telephone system May 31, 2005

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1 K-Net VoIP telephone system May 31, 2005 Description. The K-Net VoIP telephone system is an internal telephone system that uses the existing K-Net data network. Priority is given to the VoIP traffic to ensure that the quality of the service delivered is at a minimum of telephone quality. The Cisco Call Manager (CCM) is used for the phone system. Cisco IP telephones are used. At the time of tender, CCM was the only IP based phone system that was able to meet the needs and requirements of Keewaytinook Okimakanak (KO). Cisco s Unity service is used for voice mail. This ties in well with the CCM. Cisco routers are used for the gateways to bridge calls between the IP and public switched telephone network (PSTN). The CCM, Unity, and Gateways provide a scaleable and flexible IP telephone solution. At present there are gateways in Sioux Lookout and Balmertown. The gateway in Toronto and Thunder Bay (owned by the Education Network of Ontario) has been recently taken offline as part of their restructuring plans. KO will be in discussions with NAN and others in Thunder Bay to see if there is interest in sharing a gateway in Thunder Bay. For KO, the sharing of a CCM means that calls can be transferred across the network irregardless of the location of the phone. Incoming calls on the toll free lines are received by the gateway in Sioux Lookout, then transferred to the CCM. Depending on which toll-free number is used, callers are directed to the appropriate interactive voice response (IVR). Outgoing calls are directed to the appropriate gateway. Calls for Balmertown and region are directed to the Balmertown gateway. Calls for Sioux Lookout go to the Sioux Lookout gateway and all long distance is directed out the Sioux Lookout gateway where the PRI is located. KO staff are located in Balmertown, Sioux Lookout and Thunder Bay. Additionally, Community Telehealth Technicians, KiHS teachers, teacher aides and community technicians are part of the IP telephone system. There are presently 230 phones and 100 voice mail accounts. The Deer Lake school has a Cisco Call Manager Express (CCME) within it's building. The CCME is a scaled down CCM with Unity voice mail. The sizing is for smaller buildings and scales up to a maximum of 120 handsets. By contrast the CCM scales to 2500 handsets. The Deer Lake school CCME is being administered by the local technician at the school. As part of the technology transfer and the creation of economic development opportunities, it was recognized that communities should be running their own IP private branch exchange (PBX) rather than simply being consumers on the main KO PBX. Research was launched to see if this was feasible.

2 During the time the original CCM was purchased in 2001 and now, there have been advances in VoIP technologies, standards, protocols and equipment. One of the more notable advances was the emergence of session initiated protocol (SIP). The Cisco system uses their own proprietary protocol. The SIP protocol is standards based and is well documented. Digium, a manufacturer of voice gateway cards has supported the development of Asterisk. Asterisk is an open source IP PBX project that has matured and offers a good robust set of tools for someone to develop their own PBX. The issue of installing CCM in each community is one of cost and remote maintenance. Maintenance is purchased from Cisco on a yearly basis. Both software and hardware support must be purchased. Additionally, only approved hardware may be used, including specific memory and hardware. For Unity, the licence is tied to the specific network card. This adds complexity and costs to maintaining a series of CCMs across a remote network. Upon further investigation and testing, it was decided to work with the Asterisk software to create an IP PBX that would offer the following advantages. - be able to run on a wider variety of hardware; - be able to be remotely managed and to a degree rebuilt if required; - offer more flexibility for features and how to implement them; - be able to work with a centralized numbering hub; - be cost effective for other groups to use, if they choose. Two projects were identified. The KO communities funded under the FedNor IP Telephone initiative and the community of Slate Falls under the BRAND-FedNor- NOHFC development. A contract with Dades.ca of Toronto for an initial Asterisk build was entered into and completed. Then the project was moved inhouse for customization and to meet the specific needs of the different environments. For Slate Falls, this was to become their primary phone system. For the KO communities, this was a secondary phone system designed to offer flexibility and some cost savings by routing some long distance calls between IP phones over the community's network connections. Specifics of the projects are as follows. Slate Falls. As this is their present primary phone system, the Asterisk system was heavily modified to be used in high availability (HA) mode. There are two asterisk servers in place so if one goes down the other takes over with no loss of service or voice mail. The offline server can be repaired and brought back online. If necessary different server hardware can be inserted in it's place. Fairly quick turnover can be done. Automated monitoring of the servers will be implemented. The gateway used is in Sioux Lookout. At present, Slate Falls is sharing the K-Net PRI. Each phone user is issued a phone number from Sioux Lookout. The number corresponds to the phone extension in Sioux Lookout. A choice of Cisco phones and analog telephone adaptors (ATA) are offered for purchase by the residents of Slate Falls. A local technician is charged with the job of commissioning the telephones and assigning the available phone numbers. At present

3 there is a fifty subscriber waiting list for the phones which are in transit from the manufacturers. The KO Communities. The KO communities needs were not as extreme as those of Slate Falls but if and when the Asterisk server becomes critical to the community or organization, it will be trivial (comparatively speaking) to upgrade the server to HA mode by adding a second server and enabling some software features. A Cisco gateway from a previous project (the local health centre s gateway) will be utilized for local dial lines. Up to eight regular phone lines can be supported on the box. This will allow local dial incoming and outgoing from IP to PSTN and vice versa. PSTN to IP to PSTN calling is not configured as this may fall under the venue of toll avoidance. For the community servers to communicate with each other, they make use of a centralized Asterisk Hub server. The HUB server keeps track of which server has which local dial plan and which gateway to use for local dialing. This permits better scaling without having to make changes to servers in the field whenever a gateway is available or not. The KO First Nations participating in this initiative include: Fort Severn Keewaywin North Spirit Lake Deer Lake Poplar Hill The HUB box is located in Sioux Lookout. Interoperability between the CCM and the Asterisk box will be via the Hub box. Issues of dial plans and extensions are an ongoing item as the system expands and undergoes upgrades. Lessons learnt. What works. The basic premise of VoIP is still sound. It has worked out in saving long distance to a degree and in consolidating services and lines. A very good and in-depth knowledge of VoIP in the marketplace is now in place with the Kuhkenah Network team. The ability to run VoIP over terrestrial and satellite networks and in multiple environments is being accommodated as part of the K-Net helpdesk services being offered to the various programs and service providers.

4 What doesn't work so well. There was some disappointments in the conferencing features that were offered with the CCM. This did not work out exactly the way that was planned. The issue is one of codecs. Audio calls can use different codecs. ( encoders/decoders) for the various voice qualities. G729 is a compressed audio call and uses 24 kilobits of bandwidth. G711 is a higher quality codec and uses 80 kilobits of bandwidth. Due to higher than anticipated bandwidth demands for Telehealth and video conferencing, most calls must use G729 between communities. The conferencing features use G711 only. The workaround to this is to install a hardware transcoding server with digital signal processors (DSP). This is being considered. Additional bandwidth in the various locations on the network would also support the present conferencing system. Future plans. Convergence between video and voice is being planned. Software upgrades to the CCM and the Accord Video bridge are in the process of being done. New dial plans will need to be implemented as well as testing and planning. Softphones are being used by a few of the staff. Feedback from this will determine if this is a viable item to have as more and more hotels offer broadband access. Given the initial success with Asterisk, KO may look at distributing the voice mail system especially as it expands. A voice mail server in Balmertown and one in Sioux Lookout will allow the voice mail to be closer to the users and lessen the traffic on the broadband pipes. Additionally, the discussions ongoing at present with the carriers may offer more bandwidth for the same price negating the need for more boxes. More on this as information becomes available to make determinations. The competition to CCM is catching up. What was once available only to Cisco is now available to others and they are creating pricing pressures and bringing features for lower costs. It is conceivable that the CCM would be supplanted by another manufacturer's product. Additionally, Nortel's Business Communications Manager (BCM) is being brought in for testing and evaluation. This is to determine if it would be a good fit for Health Canada's (HC) IP rollout in the Sioux Lookout Zone District. The rationale for looking at this is in case HC is more comfortable with a product from a major vendor. In a related area, there is some preliminary research being done into software radios. This is where the frequencies, algorithms and encoding schemes are done entirely in software. One possibility in this will be in standards adaptable cellular systems that talk to cell phones on one side and have an IP connection on the other. This is a definite promising area and has potential for some advanced technologies and use of the technology. Overall, the experience has been a positive one and it has brought about benefits that

5 were not initially apparent. We are grateful to FedNor for their funding and monitoring efforts in this project as well as our other partners for their support. Sincerely, Dan Pellerin Network Manager K-Net Services