QoS on demand in multi providers network
Let us take the organization of QoS on demand service for videoconferencing as an example to illustrate the idea.
Nowadays, it's getting more and more popular among different organization to use internet service for video conferencing with remote branch offices. This type of services claims higher quality of channels and, in particular, requires guaranteed transmission rate from its source to its destination. But providers ISP (internet service provider) can guarantee the required QoS (quality of service) only in their area of responsibility. For this reason, many users refuse traffic transfer through the internet and have to lease expensive communication channels with the desired QoS.
Implementation of the idea would reduce users' expenses and make leasing of the special channels unnecessary. The realization of the idea is more or less easy, since the infrastructure of the internet is based largely on the equipment of one producer - Cisco.
The major components of the system are:
- QoSPS (QoS Planning Server). QoSPS is in the internet and has the following main functions:
- Receiving users' requests for reserving quality of the communication channel.
- Dissemination of the QoS policies to the ISP routers and their coordination.
- Tariffication of the services and mutual accounting.
- "QoS helper" is a program running on the user's computer, which performs the following major functions:
- helps users define the necessary Data Flow (source, destination, etc.).
- classifies it (Best-effort, Rate-sensitive, Delay-sensitive).
- detects the route of the traffic (a list of routers).
- makes a request on the QoSPS server for providing the required QoS for the Data Flow in the specified period of time.
- ISP Routers - routers with updated software which allows interacting with the server QoSPS and applying the specified QoS policies.
QoSPS - Quality of Service Planning Server
Here's an example of a typical scenario of how the system works:
Mr. Smith would like to hold video conferences with Mr. Bob each week, on Wednesdays from 11-00 to 12-00. Mr. Smith runs QoS Helper on his computer and collects the necessary information to make a request for the reservation. QoS Helper delivers the request to the QoS Planning Server. In a little while the QoS Planning Server gives the answer with the decision on the possible execution of the request.
The decision is made on the basis of responses of the ISP routers to demanded employment of the QoS policies in the specified period of time. In case of positive decision all the ISP routers would apply the demanded policies at a certain time and Mr. Smith would receive a channel of proper quality, video conference would take place.
We think that the idea possesses a big potential because it brings benefits to all. The user enjoys the simplified procedure of ordering and paying for the service. He works exclusively with QoSPS and receives a guaranteed quality channel for little money.
ISPs get additional income selling their resources at a higher price. The owner of the QoS Planning Server gets income from the organization of the process. ISP has no need to send bills to users; the provider’s service will be paid by the QoSPS owner. The whole thing is simple and transparent.
Certainly, there are many different issues to think of: the development of protocols of interaction between QoS Helper, QoSPS and ISP routers, procedure for coordinating policies, proposed by the QoSPS and those of the local providers. There are also institutional and judicial issues concerning the QoSPS owner and providers and the issue of tariffication and payment to solve.
In the future, if the idea is successfully implemented, it will be possible to distribute not only the QoS policies to the routers of the providers, but also policies of routing and filtering traffic policies. Of course, all this would be done under the authority given by providers. Simply speaking, it will depend on how far the provider will let his equipment get managed.
The idea has two more positive aspects:
- Centralized approach to managing the QoS policies can improve the overall productivity of existing network significantly with no additional expenses on the new broadband traffic and high-efficiency equipment.
- Ordering and paying for the service will be consolidated for the user in one partner – the owner of the QoSPS. So, the scheme of the cash flow "User-ISP" will be modified into "User-QoSPS-ISP." This feature creates a good background for the change in the general order of mutual accounting between users and the internet providers.
Eventually, it will be possible to let the user pay for the quality of service instead of the downloaded Megabytes and the channel. One of the possibilities is to determine a payment amount, depending on the "distance" (the number of ISP) involved in the chain of the service. It's the same mechanism as in cellular networks - the bigger the distance between the subscribers, the higher the fee. This could moderate the appetite of insane surfers and relieve the network.