Monday, November 14, 2011

Sulum Optimization

Bo Jensen at announced the availability of a new commercial LP solver. Some first impressions:
  • LP (+network) only for now, MIP will come later.
  • Aggressively priced compared to the big ones (Cplex, Gurobi). I can see this can be a very attractive offering in certain cases.
  • But it has a nasty license manager (somehow I always have troubles with these). The other commercial guys have similar drawbacks.
  • I think if you have a single license you can solve one LP at the time (a result of the previous point).
  • Low level API. In many cases, to be efficient you will need to use some more advanced modeling tools.
The product seems to be well-positioned between the Open Source offerings such as Lp-Solve, GLPK and CBC and the heavy guns (Cplex, Gurobi, Xpress).

Update: Unfortunately Sulum Optimization Tools are discontinued as per June 2015.


  1. First of all thanks for mention our company. Let me address the points you raise.

    1) Correct MIP will be released in 2012

    2) Yes, we use a license manager, which most vendors do. IMO it's fair to have a certain control against misuse. But to tell you the truth, license managers are mostly being used to protect the user. Users don't count licenses, many users could quickly be out of complience. We use RLM license manager, which is build by the original people from flexlm (most widely used manager), I see little difference from RLM to flexlm in terms of use.

    3) Yes, license is based on a floating license system (which is less restriced than some other vendors). One license token grants you the right to solve one problem at any given point in time. We do also offer server licenses, which I think is going to be even more popular, since it is simple and fits well with the future.

    4) Currently we have a lowlevel C Api and object oriented C++ and .NET i.e you can model constraints like :

    cons[i] = 0.5*vars[j]+6*vars[j+1]


    We will extent with more API's later on, but right now most focus are on optimizers. Besides we have an MPL (Maximal Software) integration, which you can use for modeling.

    I hope I answered your questions.

  2. The sentence about a license manager is really for the benefit of the user sounds like it is coming from some license manager marketing material.

  3. I frequently get the question from our MOSEK customers. How many license do we own? So there is need to keep track of them. Also I would like to point out there is difference between an API and a more GUI like application such as Word and GAMS.

    So I think software like API needs a license manager. There are drawbacks but there is no way around it if you want some money each month to pay your salary. I really hope that someone will prove me wrong practice.

  4. I can understand why you would think it's from marketing material, but that's really my opinion. There are bad examples in the software industry, where customers unknowingly were out of complience and ended up being charged large amounts by the vendor. But as Erling pointed out the license manager is of course also there to ensure the vendor get's the correct payment.