vendors outwith the group cannot guarantee lower physical equipment cost ,lower interoperability. maintenance costs. Heavy congestion on the network can Weaknesses: result in considerable degradation of service as IP is not good at providing QoS While there are many aspects of (Quality of Service) guarantees. Feedback to VoIP which provide considerable benefits, Lucent Technologies customers reflect this the technology is still very young and worry. Major companies are planning to problems remain. The following section install IP Telephony capabilities at some looks at some of the weaknesses of this point and have carried out initial technology and their consequences. investigations, however: The Internet is not the best medium for Since only one physical network for both real time communications. Individual data and voice/fax transmissions is required, packets can take different routes and varying failure of the network could be catastrophic, delays can be encountered and packets lost as all communications capabilities are lost. in transit. Waiting for delayed packets or retransmission of lost packets can result in considerable degradation of quality. Long Opportunities delays in transit can affect quality so much that the technology can become unusable, Many vendors offer the ability to though many vendors do have solutions incorporate Virtual Private Networking (VPN) with relative ease into the IP which aim to negate the degradation suffered due to transit delays. Telephony solutions they provide. This While some standards have been set by allows any transmission to be encrypted the ITU, the technology is not fully using a number of cryptographic techniques standardized and there is no guarantee that and providing security by transmitting the products from different vendors will be communications through a 'tunnel' which is interoperable. Some vendors are trying to set up using PPTP (Point-to-Point Tunneling resolve this problem by forming groups and Protocol) before commencing making guarantees about the products in the communications. group but this is only a partial solution -
lower physical equipment cost ,lower maintenance costs. Weaknesses: While there are many aspects of VoIP which provide considerable benefits, the technology is still very young and problems remain. The following section looks at some of the weaknesses of this technology and their consequences. The Internet is not the best medium for real time communications. Individual packets can take different routes and varying delays can be encountered and packets lost in transit. Waiting for delayed packets or retransmission of lost packets can result in considerable degradation of quality. Long delays in transit can affect quality so much that the technology can become unusable, though many vendors do have solutions which aim to negate the degradation suffered due to transit delays. While some standards have been set by the ITU, the technology is not fully standardized and there is no guarantee that products from different vendors will be interoperable. Some vendors are trying to resolve this problem by forming groups and making guarantees about the products in the group but this is only a partial solution - vendors outwith the group cannot guarantee interoperability. Heavy congestion on the network can result in considerable degradation of service as IP is not good at providing QoS (Quality of Service) guarantees. Feedback to Lucent Technologies customers reflect this worry. Major companies are planning to install IP Telephony capabilities at some point and have carried out initial investigations, however: Since only one physical network for both data and voice/fax transmissions is required, failure of the network could be catastrophic, as all communications capabilities are lost. Opportunities Many vendors offer the ability to incorporate Virtual Private Networking (VPN) with relative ease into the IP Telephony solutions they provide. This allows any transmission to be encrypted using a number of cryptographic techniques and providing security by transmitting the communications through a 'tunnel' which is set up using PPTP (Point-to-Point Tunneling Protocol) before commencing communications.