As enterprises strive to converge voice, video, and data over LANs and WLANs, they will face multiple challenges. Some of those challenges are technical, and a significant number of them are business related.

Technical Challenges

The main technical challenges involved in building converged networks are as follows:

1. New voice backend–Moving voice from a circuit-based network to a packet-based network involves a radical change in the voice backend. While traditional PBX manufacturers support such a change, a lot of companies can take the opportunity to start fresh with a native VoIP solution. The move should affect user services as little as possible.
2. Quality-of-Service–Introducing different services with different network characteristics into the same network requires the ability to prioritize more time-critical network users such as VoIP over less time-dependent services such as data. Introduction of QoS involves a significant technical challenge and may require a network equipment update and refresh.
3. Security–As different networks merge into a single infrastructure, the separation offered by different transports and cabling is lost. In traditional voice networks the only way to access other users' traffic is to physically gain access to their phone cabling or break into distribution frames or PBXs, which are normally locked up. With shared networks, if the network is not protected properly, unauthorized access to other users' data (and therefore VoIP) may ensue without physical attachment with methods such as ARP poisoning.
4. Training–Support staff are used to working with the legacy equipment and will have to be trained on the new equipment. Since this is a paradigm shift for most support staff, the required training is extensive. Most organizations have separate support personnel for data and voice; with the integration of voice and video on one data network, support should also merge for better end-to-end service quality.
5. Troubleshooting–The resulting converged network is more complex than its component parts. Putting more eggs in the same basket always makes it more difficult to find out the root cause of problems. To make the converged network successful, the right management and troubleshooting tools have to be created for the support staff.

Business Challenges

Besides the above, there are multiple business-oriented challenges that should be addressed before converging networks:

1. Making the business case (Return on Investment, ROI)–Probably the single biggest challenge for anyone wanting to make the leap is making the case for this move. In today's business environment changes of this magnitude are unlikely to be approved without a hard dollar calculation showing real savings.
2. End user expectation reset–Today, end users are accustomed to very high availability of their voice network and in converged networks that expectation should be level set.