Voice Over Internet Protocol – Challenges

Voice over Internet Protocol (VoIP) technology is getting increasingly popular. However, the technology that accommodates data and telecommunication streams, converting to bits and bytes, also faces a host of challenges. Let us look at the challenges that are haunting VoIP service providers worldwide.

Service Quality

VoIP is still not well organized in several countries, resulting in a low standard of service. By default, IP routers handle voice traffic on a first-come, first-served basis. Traffic on high volume routers might exceed permissible thresholds for VoIP. Steps have to be taken to minimize latency by marking voice packets as being delay-sensitive with high tech methods such as DiffServ. When the load on a link grows so quickly that the queue of data packets overflows, congestion results and data packets are lost. For effective voice traffic services, engineers have to derive ways to take care of such issues.

Trust Models and Identification

A big challenge of using the online communication medium is that any mode of communication is inherently open to any security concerns. One of the most common issues is that of Identity and Trust. In the context of VoIP, it is about subscriber and network identity and trust. As the Internet is a distributed environment with no central control, the trust model and identification becomes important. At the basic level, the questions that have to be asked and answered are – “Can the Network trust the subscriber?” and “Can the subscriber trust the network?” To address this issue, a mutual authentication mechanism is used where both the sides can verify each other. One such example is establishing an IPSec tunnel between the client and the network.


SPIT (spam over Internet telephony) is unsolicited bulk messages broadcast over VoIP (Voice over Internet Protocol) to phones connected to the Internet. Though voice mail is already used for commercial messages, IP telephony makes a more effective channel because the sender can relay messages in bulk instead of dialing each number separately. Unscrupulous marketers use spambots to harvest VoIP addresses or hack into a computer used to route VoIP calls. As the calls routed over IP are much more difficult to trace, the potential for fraud is greater here.

As IP telephony is still not widely used, this is not a big problem yet. However, as it becomes common over the next several years, it would become more attractive to spammers. Several vendors are developing products intended to address the problem.

IP Spoofing

IP spoofing is actually a lower level security issue. It is a concept where a rogue client can use a raw socket interface and spoof it’s IP to relate to other nodes. IP level spoofing can be taken care of in several ways including strong sequencing algorithms packet filtering. With modern technology, the problem of IP spoofing can be resolved efficiently.

Susceptibility of Power Failure

The susceptibility of a phone service to power failures is a common problem in several areas, specially in those regions which have traditional analog service in areas. VoIP service providers can take care of this problem by using customer premise equipment with battery-backed power supplies to assure uninterrupted service for up to several hours in case of local power failures.

All VoIP service providers have a stake in finding effective solutions to these challenges. The future of VoIP technology worldwide actually depends on how we tackle these challenges.