Internet Protocol (IP) is currently the dominant networking technology but it does not include the facilities needed to support many of the key services for which it is now used. For instance:
Quality of voice-over-IP, streamed radio programmes, etc, is uneven; every so often the sound is interrupted, or becomes distorted.
Communications service providers cannot charge users for access to "premium-rate" services.
Systems for detecting where users are located are unreliable.
A client connecting to a server cannot be reliably identified.
A broadcaster cannot easily send one stream that is copied to many listeners.
End-to-end delay ("latency") cannot be made small enough for some applications (particularly in live sound).
These issues are a result of the packet switched store-and-forward technology at the core of IP networks. Various "sticking-plaster" measures are used, but they cannot provide a complete solution. Moreover, they increase the complexity of the system, thus increasing costs and power consumption and reducing reliability.
In the Internet, these problems will become worse with the addition of increasing amounts of television to the existing traffic.
Nine Tiles has over 25 years' experience of developing digital networking systems, and has always designed them to be easy to use and maintain.
Flexilink builds on that experience to provide a reliable and cost-efficient service both for time-critical media, such as live audio and video, and also for IT-related services such as file transfer and web browsing.
Flexilink is ideal for all applications in which live media are conveyed, from broadcast infrastructure, CCTV, public address, and sound reinforcement to home entertainment. As the name suggests, it is flexible enough to provide efficient transport for audio (frequent short packages), video (larger packages), and packet data (bursty traffic).
It provides all the benefits of circuit switched technologies such as ISDN, for instance guaranteed QoS and low latency, while avoiding problems such as fixed cell size or channel capacity, expensive hardware, and labour-intensive network management. It also supports IP, for compatibility with the current Internet and for use with those applications for which packet switching is more appropriate.
Features include:
Can use a variety of physical formats, including Ethernet and SONET/SDH
Linear segment ("daisy-chain" concatenation of point-to-point links) eliminates need for star-connected switch in small systems
Supports multiple paths for resilience
Tight synchronisation and small minimum package size minimise latency
Better QoS and less overhead than ATM or IP
Lightweight protocols minimise logic complexity
|
ISDN |
ATM |
IP |
Flexilink |
low hardware cost |
|
|
|
|
linear, star, or ring configuration |
|
|
|
|
good QoS for live media |
|
|
|
|
flexible bandwidth allocation |
|
|
|
|
low complexity protocols |
|
|
|
|
easy for users to configure |
|
|
|
|
Several aspects of the design of Flexilink improve the user's Quality of Experience:
Delays and lost packets in media streams are virtually eliminated.
Changes in topology, such as links being connected or disconnected, are signalled promptly and explicitly. This makes diagnosis much easier, for instance when a piece of equipment fails to communicate it is immediately obvious where the problem is.
Addressing of units and services is more flexible, eliminating problems with DHCP, Network Address Translation, etc., and making firewalls easier to configure.
Within a local area (such as a home or small office network) an application can "crawl" the network, finding what equipment is available (though any unit or subnetwork can be concealed if required for security) and offering it in a menu to the user.
The protocols for carrying media streams and other traffic will interwork with protocols such as SIP and RTP which are used in the current Internet. Therefore, "islands" of the new technology can be used to replace or augment parts of an IP network, with translation between the different protocols at the boundaries. Calls that are completely within an island will benefit from the guaranteed QoS and low latency, and calls that cross an island will experience an improved service if they previously crossed a part of the network that was liable to become congested. These "islands" can then be expanded, and where they meet they will coalesce into a single, larger island.
The technology will initially be implemented in the following product groups:
Brunhilde Flexilink interface for end equipment, similar to the current Brunhilde technology.
RouteLive Flexilink switch, similar to the current RouteLive switch.
Follow these links for more details of:
------------- ooo OOO ooo -------------
Copyright ©2007 Nine Tiles Networks Ltd
