Contention Ratio

When booking a shared Internet Service via Satellite the contention rate should inform you about the numbers of users you are sharing the subscribed bandwidth with.  E.g. with a 1:10 ratio you share the bandwidth with 9 other users.

In reality, your a satellite provider however not shares ONE specific satellite stream among the number of users he does specify.

Satellite technology not works like this.

In reality a provider operates a large satcom carrier, which he shares among all the different service grades he does operate. For this reason, large services do fluctuate higer in bandwith than smaller ones.

The "sharing" is created by IP QOS rules. Not by "overbooking or sharing".

Some manufacturers of hub equipment do call the underlying technology to manage IP service quality "GROUP QOS". It is very easy for  a provider who not understands his job, to misconfigure the GROUP QOS he does operates. Most not even recognize their misconfiguration, but send their customers a bad service.

Overcongestion effects such as "stall of bandwith speed" the result.

This has had terrible influence to the whole satellite internet industry.

Overbooking services als not is performed most of the time with STICKY CIR, but dynamic re-allocating CIR. So call MIR. 

This Most of the time available internet rate (MIR) is not giving the customer any guaranty, that he really does receive a certain minimum datarate at all.

This circumstance has resulted, that the whole satcom industry has deterriorated as customers where not receiving the service quality they did expect.

 There are very few providers, who really do guarantee the ratios and do not overbook them, by assigning hard comitted sticky CIR. 

The CIR bandwidth - which is the minimum available bandwidth also during peak times.

What out what you get really offered, in order not to compare "Apples with Eggs".

CIR > Committed Information Rate

Committed Information Rate (CIR) is based on an ITU-T Standard. CIR is the minimum available bandwidth guaranteed by a provider under normal network conditions.

We strongly can recommend all customers in the professional area, to insist on hard comitted CIR type services. 

All Level421 Services include CIR and this provides our clients an outstanding service reliability, stability and performance.

MIR - Maximum Information Rate

Maximum Information Rate is a term not dfineing any minimum or guaranteed bandwith. It simply just specifies a data rate a link maximum or most probably can have under good or uncogested conditions.


We strongly recommend customers to stay away from SLAs who use the term MIR, as the MIR theoretically also can be ZERO.